Apartments

We_need_to_talk_about_apartments_20_7_2022

 

 

[Image appears of Anthony Wright talking to the camera and the other participants can be seen in the participant bar at the bottom of the screen]

 

Anthony Wright: Welcome everyone to the second of our webinars for 2022, this one on apartments. This webinar has its origins in an article my colleague Michael Ambrose wrote about apartments, which garnered a whole lot of attention on LinkedIn and elsewhere, and made me think, well there’s probably a bit of interest out there and we should, we should have a chat about it. But before we get into that, I’d just like to acknowledge the Traditional Owners of the land I’m speaking from, the Wurundjeri People of the Kulin nation and pay respect to their Elders, past and present.

 

And we’ve got today four speakers. We’ve got my colleague Michael Ambrose who’s going to give us a run through of some data on apartment buildings from the Australian Housing Data Portal. Following Michael, we’ve got Alex Zeller from the Australian Building Codes Board, who’s going to have a chat about some of the features of apartments that matter for energy efficiency. PC Thomas from Ten Catalyst is then going to get into some more detail on apartment modelling and comfort. And David Eckstein from ex-City of Sydney, and David you’ll have to correct me if it’s Eckstein not Eckstein. I’ll go with Eckstein unless you shake your head at me. David has recently left that position but has a very broad background in having a look at the apartments that come through for compliance purposes, looking at plans and permits and so on, and seeing what gets done well, and not so well.

 

[Image continues to show Anthony talking on the main screen and participants can be seen in the bar at the bottom of the screen]

 

In the spirit of kind of, you know, engaging with the people who are sometimes critical of what goes on in the NatHERS scheme and in modelling, I think we’ve got quite a few dissenting voices here, and I think apartments is a really interesting thing to, to kind of consider. It’s worth remembering that there’s very, very little information out there on how actual apartments perform under the NatHERS scheme or under any of the kind of compliance methodologies in the code.

 

I don’t think I’ve ever seen a study that comprehensively went in and evaluated sole occupancy units in an apartment building and determined how well our kind of minimum standards were working or how well our modelling was predicting those outcomes. I’ve certainly seen people say that modelling doesn’t do things well and that’s true on a whole range of fronts and I’ve seen on the converse people build high performance apartment buildings and claim that the actual energy consumption is significantly lower than the modelling might have estimated in the first place, so the diversity of opinions out there is, is huge and I think it’s probably a question that we too often put aside when we’re considering some of the regulations and some of the, the kind of ways we build our apartment buildings in Australia.

 

Lots and lots of people live in houses and everyone seems to default to houses as the, the kind of, I suppose, default building form when we’re talking about energy efficiency but apartments are increasingly a large portion of our stock and I think it’s probably time we spent a lot more time thinking about how we model them, how we rate them and how we test them for compliance and so on. So, I’m hoping this webinar kickstarts that conversation.

 

[Image continues to show Anthony talking on the main screen and participants can be seen in the bar at the bottom of the screen]

 

We’ve got four fabulous speakers to talk to you. I’m going to play pre-records of their presentations and then we’ll have some Q&A at the end. Just for housekeeping, those of you that have been to these webinars before know that we have a Chat function on the right-hand side of your screen. In that Chat function, you can talk with each other and have a conversation and, and basically comment on what the speakers are saying, but those chats don’t come through to me or to the speakers. In that Chat, you have Lachlan and someone called Vbrick Admin, our very own Eric Weckmann from the CSIRO, who are there to help you with any technical problems. So, if you’re having trouble hearing or seeing the video or something along those lines, please drop that into the Chat and Eric or Lachlan will help you out.

 

If you do have a question for our speakers, there’s a Q&A box where you can enter the questions for the speakers. They will come through to me. I will prioritise them or group them and then direct them to our speakers in the Q&A session at the end of the presentations. Please make sure you get your questions in there. It’s always good for a robust debate to have lots and lots of questions and we can sometimes try and answer your questions out of session if we don’t get to them all, so please drop your thoughts in there rather than saving them up for the end and we’ll get our speakers to see if they can address them for you. So, I think that’s it from me for now. I will hand over now to Michael Ambrose who’s going to have a chat to us about the, what the Australian housing data portal and our NatHERS certificates say about apartment buildings. So, give me a minute and I will share his video with you.

 

[Image changes to show a new slide showing a photo of a multistorey apartment building in construction, and Michael Ambrose can be seen inset talking to the camera, and text appears: Apartment energy efficiency, How energy efficient are new apartments, Michael Ambrose, July 2022]

 

Michael Ambrose: Good afternoon. My name’s Michael Ambrose. I’m a Senior Experimental Scientist here at CSIRO and I’m going to be giving a quick talk today about the work that we’re doing in apartments, looking particularly at the energy efficiency and star rating of new apartments that we collect in our NatHERS database.

 

[Image changes to show a new slide showing a building class number, and a building class percentage bar graph at the bottom of the screen, and Michael can be seen inset in the top talking, and text appears: Apartments are booming, 61,000 Class 2 certificates issued in 2021, 78.4% of these in NSW, 55.6% or all certificates issued in NSW, 33.4% or all certificates issued in ACT]

 

As you are probably all aware, apartment, the apartment market is actually booming, particularly new apartments and in 2021, we had 61,000 Class 2 NatHERS certificates issued on our system. Now, interestingly, 78.4% of these were in NSW and, and within NSW, the majority, so 55% of all NatHERS certificates issued were for Class 2 certificates. So, you can see here the split there that we had. The majority of certificates in NSW are for Class 2s. Now in most other jurisdictions, we had a much more traditional split between Class 1 and Class 2, but the ACT did have 33% of the total certificates issued there being for Class 2. So, certainly in the ACT, we are seeing an increase in the amount of apartments, as well.

 

[Image changes to show a new slide showing a line graph of star rating, and table of star ratings by state/territory for Class 2 apartments, and Michael can be seen inset in the top talking, and text appears: Star ratings, Minimum star rating required to be in the top 15%]

 

Now, as far as star ratings go, apartments tend to outperform houses. Since we started collecting NatHERS data, we have seen a steady increasing trend in the star rating of apartments to the point now where over, over 50% are rated above 6.5 stars and if we looked at the same data for, for homes, we find it’s only 24% for houses. Now this rising star rating average also means that if you want to claim that your apartment development is one of the best, the benchmark is actually quite high. These numbers here are looking at the minimum star rating required to be in the top 15%. So, nationally if you wanted your apartments to be in the top 15% then you need to have a star rating of 7.7 stars and if you’re in the ACT, you would need to have a star rating of 8.6 stars to be considered at the top performing apartment. Now, again, if we looked at houses, you only need to achieve 6.8 stars nationally to be in the top 15%. So, certainly apartments are performing, as far as modelling goes, performing much better in the star ratings than houses do.

 

[Image changes to show a new slide showing Class 1 and Class 2 bar graphs for star rating, and Michael can be seen inset in the bottom talking, and text appears: Star Ratings, Average star rating for apartments is 6.6 stars, Average star rating for house is 6.2 stars, Almost 40% of apartments at or above 7 stars compared to 11.4% of houses, 30% of apartments below 6 stars compared to 19.5% of houses]

 

But star rating of apartments does have its own challenges. As seen, on the previous slide, no more than 50% rate above 6.5 stars and indeed the average is 6.6 stars, while for houses, the average is 6.2 stars so only just above the, just above the minimum compliance, and when we look at the star rating distribution, we see quite a different profile from apartments to houses. For houses, minimum compliance rules the roost, so we see this large spike around the 6-star, 6-star minimum and, and a rapid drop off then on either side so you can see there that we have either side of that 6-star mark we have drop offs. For apartments, we see a much more even distribution. You can see here, we’ve got a much more even distribution around their average with many more apartments achieving higher star ratings and indeed we have 40% of apartments rate at or above 7 stars, compared to only 11% of houses. However conversely, we also see a much larger proportion of apartments with lower ratings, so like 30% of apartments rate below 6 stars, compared to only 19.5% of houses. Now, I’m sure that many of you will know the reason we see this type of distribution in apartments and, and not houses. And that’s what we’re going to talk about a little bit next.

 

[Image changes to show a new slide showing two bar graphs showing average star rating of apartment blocks in Sydney and Melbourne, and Michael can be seen inset in the centre talking, and text appears: Star Rating Averaging, 150+ Apartments – Melbourne, Average 6.2 stars, 47% below 6 stars, 23% rated at or above 7 stars, 450+ Apartments – Sydney, Average 7 stars, 16% below 6 stars, 5 apartments below 5 stars]

 

So, as many of you know, when it comes to rating apartment developments, it’s an averaging process that is used for compliance purpose, so Section J, requires apartments collectively achieve an average star rating of not less than 6 stars, and that individually achieve an energy rating of not less than 5 stars. So consequently, it’s not surprising that we see a star rating distribution around this, this average, around this average mark. However, what might be surprising is how this distribution can look within actual developments. Now we’ve been able to create profiles for over 5,000 apartment developments across Australia and we see a wide range of distributions in play that lead to that all important average star rating, and I’ve just pulled up two distributions here as examples of what we see. There’s nothing particularly special about these, these two developments. I’m purely using them for, for illustrative purposes. So, firstly, one from 150+ apartment development in Melbourne had an average star rating of 6.2 stars so pretty much minimum compliance. Because this is based on the average, we actually have 47% are below the 6-star mark. Still compliant of course, but did the purchasers know what their apartment rated?

 

And that’s sort of the critical question here. Now, maybe for an apartment development that is only going for minimum compliance, maybe purchasers are less interested in the energy performance of it, but what about apartment developments that rate above the minimum, perhaps are marketed as energy efficient developments? So, the next one we’ve got here is a 450+ apartment development in Sydney, has a much higher average star rating, this star rating of 7 stars. So, potentially it was marketed as an energy efficient development. We do have a slightly more even distribution on this one than we had on this Melbourne one which was quite skewed to the left-hand side and this one is a more even distribution, but we still have 16% below 6 stars and we’ve got these ones down here which were five apartments which are actually below 5 stars. So, the question really is, did the purchasers of these, these five apartments here know how poorly their apartment rated, and was this reflected in the price? We don’t actually know the answer to this, but what we do know is that those apartments will most likely have a higher running cost than most of their, their neighbours.

 

[Image changes to show a new slide showing a bar graph at the bottom showing 40% below the average 7.6 star average, three 6-star builder’s stamps, and Michael can be seen inset in the top talking, and text appears: Marketing energy efficiency, Great that developers are highlighting energy efficiency inclusions, However, do they disclose individual apartment ratings?, “Minimum 7.5 star average” What does this mean?, Are we misleading consumers with “average” star ratings]

 

Now, it’s all great that developers are starting to realise the importance of energy efficiency and market their properties that way and this list here that I’ve, that I’ve put in, this is a list of energy efficiency inclusions that I found for a development in Melbourne. So, there are lots of, lots of things on this list. Some of them we might chuckle at some of the things that are probably just standard but are upsold as energy efficient. But the important one here is the statement around the star ratings. So, we have here that the, that the claim on a minimum 7.5-star average house rating. So, what does this actually mean? And how would a potential purchaser interpret this? So, would they think that the apartment, that their apartment achieved a minimum of 7.5 stars or would they be told that this is the minimum average for the development?

 

Now, I’ve included a distribution of star rating for a development in the same location. I’m not actually sure if this is for the same development that the advert’s for, but it does have an average of 7.6 stars and as you can see, hardly surprising, you have a sizable percentage are below the average. In this case, it’s, it’s going to be 40%. It’s surprising how often I have to remind people what an average is. That means there will be a distribution around the, the average mark, in this case 40% of course are below that average. So, are we definitely misleading or confusing consumers with the average star rating? We have seen in the housing industry, some builders misled consumers with their own 6-star logo on it. I’ve got a little collection of ones that we have seen being used in, in the marketplace, and they really do mislead consumers into thinking that 6 stars is the maximum achievable rather than the minimum required. So, we want to ensure that our buildings’ energy efficiency credentials are marketed fairly and, and accurately.

 

[Image changes to show a new slide showing a bar and a line graph on energy use in common areas of apartments, and Michael can be seen inset in the top talking, and text appears: Other apartment research, Energy consumption monitoring of common areas, Air pressure testing of individual apartments, Suitability of National Scorecard and NatHERS to rate individual apartments, How to align NABERS rating with apartment ratings, Energy disclosure of individual apartments]

 

Now, finally, I just wanted to quickly touch on other apartment-based research work that we are doing or that we are about to start. We have been doing a series of monitoring of a couple of very large apartment complexes in Melbourne, mainly monitoring the common area energy use to get a better understanding of the split between this and the apartments themselves. These little charts are just a bit of an example of the type of data that we’re getting from those buildings, and it really is to get that understanding of, of the energy efficiency aspects of the common areas, and to target energy efficiency upgrade opportunities that might exist in those common areas. So, the big plant equipment there. We’re also about to begin a project measuring the air tightness of new dwellings, that’s all Class 1s and Class 2s but apartments will be included in the sample mix with that project.

 

This project really aims to get a better understanding of the actual air tightness levels being achieved and comparing those to the assumed air tightness levels that we have in the model. We’re also partnering with NSW Office of Energy and Climate Change to investigate the suitability of national score card and NatHERS to rate existing apartments and how NABERS fits into this whole process. So NABERS, as many of you will know, is mainly used for a post-occupancy rating of office buildings, but it’s also used in apartment buildings as well, to look at again the common area energy consumption, post-occupancy. So, how does NABERS align with NatHERS and the scorecard and how can that be combined together. And all of this is leading to how do we do energy disclosure of individual apartments?

 

[Image changes to show a new slide, and Michael can be seen inset in the bottom right talking, and text appears on the slide: Thank you, Energy, Michael Ambrose, Senior Experimental Scientist, +61 3 9518 5998, michael.ambrose@csiro.au, ahd.csiro.au]

 

So, thank you very much for your time today and I’m happy to take any questions.

 

[Image changes to show PC Thomas’ name on the screen, and then the image changes to show Alex Zeller talking to the camera, and participants can be seen in the bar at the bottom of the screen]

 

Alex Zeller: I think you’re on mute Anthony.

 

[Image changes to show Anthony talking on the main screen and participants can be seen in the bar at the bottom of the screen]

 

Anthony Wright: Thanks, Alex. I knew I could rely on you guys to tell me when I was making my big error. There was bound to be one. Things were going too smoothly. Thank you, Michael. Last chance to get some questions for Michael into the Q&A. I’m just going to cue up Alex’s presentation now and I will share that with you momentarily.

 

[Image changes to show a new slide showing a photo of a penguin, and text appears: Shared Fabric in Apartments, “The Penguin Factor”, Alex Zeller, July 2022]

 

Alex Zeller: Thank you for that. Good afternoon, everyone. My name is Alex Zeller. I am a Senior Project Officer at the Australian Building Codes Board. I want to thank the CSIRO for the invitation to present today on energy efficiency in apartments. In this presentation, I will be talking about shared fabric in apartments. Shared fabric means the walls, the ceilings and the floors that separate one apartment from another neighbouring apartment. A light-hearted name for what we’ll be talking about is “The Penguin Factor”. And we’ll get more into that shortly. Over the course of this presentation, I’ll discuss the benefits and also the challenges of shared fabric on energy efficiency and also on ventilation in apartments.

 

[Image changes to show a new slide showing a bar graph of NatHERS Rating for Houses in Melbourne, and then a bar graph beneath showing NatHERS Rating for Apartments in Melbourne]

 

So, getting straight into some data. On screen is some NatHERS rating data from the CSIRO’s Australian Housing Data Portal. This data is specifically of new dwellings in Melbourne over the past two years. The trend is similar in many places around Australia, particularly in the cooler climates in Australia, but I’ve just isolated Melbourne here for simplicity. The main thing to note from this data is that the average new apartment is significantly more efficient than the average new house. While the average new house achieves about a 6-star rating, the average new apartment achieves about a 7-star rating. New apartments are currently, on average, more energy efficient than houses. There may be a number of different factors at play contributing to this, but one potential contributor that I’ll focus on in this presentation is the shared fabric factor, the penguin factor.

 

[Image changes to show a new slide showing a photo of an apartment block on the left, and a group of penguins huddled together on the right, and text appears: The Shared Fabric Factor (aka Penguin Factor)]

 

So, what is the shared fabric factor, or the penguin factor? One characteristic of apartments is that they are built closely packed together. An apartment may have a neighbour to either side of it, as well as above and below it and this is similar, of course, to the way that penguins in Antarctica huddle together when temperatures get very cold. They huddle to keep warm using one another’s body heat. This is so effective that even during a snowstorm in Antarctica, the middle of the huddle can reach temperatures in the high 30^o, and the penguins actually have to rotate out of the centre or else they overheat. Huddling is effective for keeping penguins warm in the winter and it can also be effective for keeping apartments warm in the winter and cool in the summer.

 

[Image changes to show a new slide showing a block representing a house, and a group of blocks together representing an apartment, and text appears: Externally facing walls, roofs and floors]

 

Looking at this another way, apartments have fewer externally facing walls, roofs and floors, than a free-standing house. Whereas a house may be exposed to external conditions on all sides, from above, from below and all around it, so let’s say on six sides of the cube, an apartment may be bordered on most of its sides by other apartments and so may have only one externally facing aspect. Heat loss and heat gain through neighbouring walls, ceilings and floors is very low. It’s effectively zero when modelled in the NatHERS rating scheme. This means that most of the heat gain and loss will be through those few faces that are left, that are externally facing. Having such a reduced area for heat exchange is a big efficiency advantage for apartments.

 

[Image changes to show a new slide showing text on a blue screen: Apartments have some energy efficiency advantages, but are there also downsides?]

 

So, these efficiency advantages that apartments have are great. They mean that all else being equal, apartments are often more efficient than houses, but for the rest of this presentation, I’m going to discuss potential challenges that may come along with the shared fabric factor, or the penguin factor.

 

[Image changes to show a new slide showing a floor plan of an apartment with the shared walls highlighted in red]

 

Let’s delve into an example. Here is a plan for a reasonably unremarkable apartment. Let’s say it’s also in Melbourne. As we’ve discussed, if this apartment was a free-standing house, it would be subject to heat transfer from all four sides, as well as through the ceiling and through the floor. Since it’s an apartment though, its two shared walls which are highlighted in red there, have a significantly decreased amount of heat transfer. When they’re modelled in NatHERS, they are actually modelled to have no heat transfer. If there are other apartments above and below this apartment, there will also be no heat transfer modelled through the ceiling or through the floor. In the latest public draft of the next version of the National Construction Code, homes are proposed to be required to have a star rating of at least 7. Because of the penguin factor in this apartment, it’s not too hard to meet that minimum rating of 7 and the few windows and walls that are externally facing, the north and the east walls and windows can be reasonably poor performing, while still receiving a good overall rating.

 

[Image changes to show a new slide showing a bar graph comparing efficiency of an Australian 7-star apartment, a USA, NZ or UK apartment, and an Australian hotel, below the text heading: Component efficiency]

 

In that particular example, the windows are actually able to have a u-value of about 6 which isn’t too far off from the lowest performing window that it’s possible to buy. These windows are about three times worse performing than code requirements in similar climates in other countries. Even in the current Australian Building Code, if the apartment was instead a hotel, or a student accommodation unit, it would require windows with a u-value of about 2, which is three times better performing than the u-value of 6 required in that apartment. It’s an interesting effect.

 

The apartment with low-performing windows is still arguably energy efficient though. It achieves 7 stars and requires just as much energy to heat or cool as a 7-star house but low-performing windows do have side effects beyond just overall energy efficiency. Low-performing windows will get very cold in winter. This might mean that it’s uncomfortable to be next to the windows when it’s cold outside. Cold windows are actually, are also at a greatly increased risk of having significant condensation occur on them.

 

[Image shows the International Standard red broken line appearing on the graph, and text appears next to the line: ISO 13788]

 

The International Standard 13788 recommends that windows in Melbourne’s climate achieve a u-value of no more than about 4.2. And this is to reduce that risk of excessive condensation occurring on the window. So, all this to say that while the penguin factor is good for overall efficiency of an apartment, it may also inadvertently lead to low-performing components such as windows in the apartment and that has potential downsides.

 

[Image changes to show a new slide showing a diagram plot of data on airtightness and ventilation below the text heading: Airtightness and Ventilation]

 

Moving on to another potential impact of the penguin factor in apartments, as promised earlier in this presentation, I’ll talk about air tightness and ventilation. This data is from a study that was completed a few years ago by the CSIRO, actually led by Michael Ambrose, who is of course also presenting today. The plot on screen shows the air change rating per hour, when a house is pressurised to 50 pascals. And this is a well-known measure of how airtight a house is. The data suggests that there is a lot of variance in the air tightness of new houses in Australia, but for what it’s worth, the average airtightness of Australian houses is just over 15 air changes per hour.

 

Air tightness is great for energy efficiency, as it means that we are leaking less of our conditioned air to the outside, and it is also a great way of minimising unwanted draughts within a home, but there is an additional consideration that needs to be made for homes that are particularly airtight or particularly well-sealed. In many building codes around the world, additional ventilation, continuous background ventilation, is required for homes with an air-change rate of less than five. Most homes are not tested for air tightness though, so some homes may be being built that are sufficiently well-sealed to require background ventilation but may not know it because they haven’t tested for air tightness. These buildings may, in effect, be under-ventilated and may have suboptimal air quality and an increased risk of condensation as a result.

 

[Image changes to show a new slide showing a symbol of a house, a fan, and an apartment, and text appears beneath: ~15 ACH₅₀, <5 ACH₅₀ , ???]

 

This data on screen is specifically for free-standing houses though, so we need to move on to consider apartments. So, based on that best data that’s available, the average Australian house might have an airtightness of around 15 and a relatively small proportion of houses might be below that threshold of five that requires background ventilation, but there is no public data on the average air tightness in apartments. We can speculate about air tightness in apartments though, although data would be ideal.

 

[Image shows a single block appearing representing a house, and a group of blocks joined together representing an apartment building]

 

So, apartments are constructed using different methods than houses are, and it may be the case that apartments are more airtight than houses and if we consider the shared fabric factor in the context of air tightness, again, houses are surrounded by fresh air on all sides and there is a lot of fabric surface area for that fresh air to potentially leak into the house. The reduced external surface area of apartments may mean that there is less opportunity for fresh air to leak in. Some air may leak in from other apartments or from the corridor, but this isn’t necessarily fresh air that will help with air quality or with condensation.

 

So, if apartments had, say one third of the fresh air leakage of a house, due to that shared fabric factor, the average new apartment might actually have an air change rate of less than five and the average new apartment may need background ventilation to maintain air quality and to decrease risks of condensation, but more work would be beneficial to gather data and actually measure the air tightness of apartments.

 

[Image changes to show a new slide showing a photo of a person placing an exhaust fan cover on an exhaust fan on the left, and an arrow pointing to a trickle vent on top of a door on the right]

And just to add some clarity about what that background ventilation might actually mean in that apartment. There are many ways to provide background ventilation to a home. There are methods that are really effective and very energy efficient, but some of these methods can also be relatively expensive. But there are also really simple, and really cost-effective ways of providing background ventilation. An apartment in Australia, for example, might choose to provide background ventilation by simply upgrading its bathroom exhaust fans to run continuously at a very low rate. The fans might operate at their normal flowrate when they’re switched on at the wall, and operate at a continuous low flowrate, when it is turned off at the wall. A small trickle vent could also be installed, as in this picture, to provide the supply of the make-up air to replenish the air removed by the bathroom fans. So, background ventilation does not need to be too complicated or too costly, and it has air quality and condensation benefits.

 

[Image changes to show a new slide showing a photo of a group of huddle penguins on the right, and text appears on the left: Summary – Shared Fabric & Apartments, Advantages, Overall energy efficiency, Challenges, Component energy efficiency, Ventilation, Condensation]

 

So, to summarise, there are advantages and challenges to the shared fabric factor, the penguin factor, in apartments. Thanks to the penguin factor, apartments can be very energy efficient but there are extra considerations that may need to be made to ensure components like windows aren’t too cold, and also to ensure that the apartment has adequate air exchange and ventilation. These two factors of lack of ventilation and component energy efficiency may increase condensation risks in apartments if they’re not adequately addressed. And that’s all from me for now. Thank you everyone for your time. I’ll be around to answer questions at the end of this session. Thanks.

 

[Image changes to show PC Thomas’ name on the screen, and then the image changes to show Anthony talking on the main screen and participants can be seen in the bar at the bottom of the screen]

 

Anthony Wright: Thanks, Alex. I don’t envy your task at the Buildings Code Board there, trying to balance all of the requirements and deliver the kind of performance people are looking for in their apartments. We’re going to move on next to PC Thomas, who has prepared a presentation for us on some more detail around modelling of Class 2 buildings. I’ll hand over to PC now. Bear with me, just a second.

 

[Image changes to show PC Thomas talking to the camera, and then the image changes to show a new slide and PC Thomas can be seen inset talking in the top right, and text appears: Evaluating Apartment Thermal Performance, Australia Residential Energy Rating, 26 Nov 2021, PC Thomas, Director, pcthomas@teamcatalyst.com.au, +61 417 405 478]

 

PC Thomas: Hi everyone. I’d like to speak to you today about rating Class 2 apartments, the thermal performance of Class 2 apartments.

 

[Image changes to show a new slide showing a floor plan and a 3D plan of an apartment block, and PC can be seen inset in the top right talking, and text appears: Class 2 – Apartment Block]

 

And to do that let’s look at an apartment block. Here’s a typical apartment block. It’s got a ground floor, which is on top of the carpark basement, fairly typical, and I’ve only shown you one middle floor, but we could imagine many middle floors on this apartment block, and a top floor which has got a roof that’s exposed to the sun. We’re only interested in these middle floor apartments and here’s a plan. You can see we have eight apartments on each floor. There are four corner apartments, which are really mirror images of each other and four middle apartments, again, which are mirror images of each other.

 

[Image changes to show a new slide showing a floor plan for a mid floor middle unit, and a floor plan for a mid floor corner unit, and PC can be seen inset talking in the top right, and a text heading appears: Thermal comfort Impact of Façade]

 

Now, if we look at the plan a little bit more in detail, we can see that these middle units, middle floor middle units have only got one exposed façade, one façade that’s exposed to the outside weather. There is this one window that faces a different direction, but let’s face, let’s say that the main orientation is here and then in this two-corner apartment, we have two external facades and two directions and two orientations, OK. So, the, I’ve also shaded in the first three to four metres away from this external façade and the reason is that any thermal comfort impacts for the occupants which are dependent on the external façade will only be felt in that first three to four metres, and the reason for that hopefully will become evident as we go through the presentation.

 

[Image changes to show a new slide showing a table of heating and cooling percentages of the total block for each unit, and PC can be seen inset talking in the top right, and a text heading appears,: Min 7-Star NatHERS]

 

So, what we did was model the, these eight units in NatHERS. So, all corner units have the same window dimensions, all centre units have the same window dimensions. We haven’t modelled any shading, there’s no insulation in the walls and therefore we played with the performance of the windows to arrive at a minimum 7-star performance. The white columns are corner apartments. The coloured columns are middle apartments. You can see the star bands here. They’re all 7 or more, OK.

 

If we look at the total annual energy consumption in this total check line, you can see that the energy budget is around the 60 megajoules per metre squared for the year, except the north which does very well, which is why we always like to buy north-facing apartments. If we then do a split of the heating and cooling as a percentage of the total budget, you can see that south requires the most amount of heating to be expected, and south-east as well.

 

[Image changes to show a new slide showing a table of data on the window performance of the apartment block, and PC can be seen inset talking in the top right, and a text heading appears: Façade (Window) Performance]

 

If we then go and have a look at the, the window performance, or the wall-window performance, then some things to look at are that the corner apartments have got a window to wall ratio around 68-71% but the middle floor, middle apartments have got almost 100% glazing. And even though they have 100% glazing, the u-value for those facades are more than that for single glass without any frame. If you look at this south façade over here, which is almost a 100% window to wall ratio on that south-facing middle apartment, this number 5.7 is really clear glass, 4mm thick without a frame, which is really quite poor performance.

 

[Image changes to show a new slide showing a table showing the minimum wall Total R-Value, and information on the walls and glazing, and PC can be seen inset talking in the top right, and a text heading appears: Wall – Glazing (NCC Vol 1)]

 

And the reason we, I represented the performance of the façade as a wall-glazing number, is because that’s already being done in the current NCC2019 for Class 3. If you look here, it’s Class 3 requirements, and Class 3 is as you know an apartment by another name. So, in Climate Zone 6, Melbourne, or 7, Canberra the u-value for the wall-glazing together should be 1.1, for Climate zone 5, which is Sydney, a u-value of 2, and you can see that’s significantly more stringent than what we see NatHERS 7-star outcome to provide.

 

[Image changes to show a new slide, and PC can be seen inset talking in the top right, and text appears: Insights, Wall glazing (façade) u-values vary between 6.5 (worse) to 2.7 (better) W/m2-K, 7 star NatHERS for Class 2 delivers very poor building façade when compared to Class 1, Will result in poor thermal performance comfort outcomes, Spaces next to external façade will swing from hot to cold very quickly, Not inequitable, can have negative health implications, https://thefirthestate.com.au/innovatioin/large-apartment-windows-desirable-or-deadly/]

 

So it, in summary, our wall-glazing u-values for Class 2, as currently being rated is two to five times worse than what is required in Class 3 by the National Construction Code and therefore the 7-star for Class 2 apartments delivers very poor building fabric, compared to what you get in Class 1. Obviously, this will be resulting in fairly poor thermal comfort outcomes and the spaces that are next to this façade will swing from hot to cold very quickly. This is not an equitable outcome, and certainly could have some negative health implications. Now, I’ve written an article about that in The Fifth Estate. You might want to have a look at it, the reason being that we’ve only got 15 minutes and I, I would not be able to give you all the details behind that.

 

[Image changes to show a new slide and PC can be seen inset talking in the top right, and text appears: Alternative Rating Methods, 1. Equivalence with Class 1 fabric performance using a ‘Shared Fabric Adjustment Factor’ – NatHERS, 2. Use a thermal comfort metric, rather than energy proxy – other software]

 

So, what are alternative methods of rating Class 2 fabric? One might be that we try to get some equivalence with a Class 1 fabric performance, using some sort of a shared adjustment factor for shared fabric, and that would work very well with NatHERS. Another might be that we look for a thermal comfort metric in each of the spaces that we are interested in, rather than the energy proxy that we are doing right now. And that thermal comfort metric process is already in the JV3 method that we use in NCC Volume 1 for Class 3, Class 5 and other buildings.

 

[Image changes to show a new slide, and PC can be seen talking inset in the top right, and text appears on the slide: Testing Equivalence with Class 1 Fabric, 1. Build idealised Class 1 model to represent Class 2, 2. NatHERS runs – run with Class 1 DTS elemental provisions to get 7-star performance, set window performance for ‘all exposed’ case, then with increasing ‘neighbour’ (shared) envelope surface, repeat for 4 orientations, 3. Review raw energy score change, 4. Devise ‘shared fabric adjustment factor’]

 

So, we tested the equivalence idea, equivalence with Class 1 fabric. We built an idealised apartment-like house, and we started the NatHERS runs with all surfaces, so we’ve got a roof, floor, walls, lots of external façade, and then slowly started to increase the neighbour surfaces so that it became an apartment. So, we got 7 stars using Class 1 and then we’ve left the fabric performance as it was and then reduced, increased the number of shared enveloped surfaces and then worked out what was the budget, compared that against the raw score for Class 1 performance and then devised a fabric, shared fabric adjustment factor.

 

[Image changes to show a new slide showing a floor plan for a unit, and PC can be seen talking inset in the top right, and text appears on the slide: Idealised House/Apartment]

 

So, here’s the idealised model that we used to do this analysis. That representation is not the NatHERS representation, but it gives you an idea of what the building looks like. So, it’s a corner unit. Two facades have got external exposure and windows.

 

[Image changes to show a new slide showing a table of data, and PC can be seen talking inset in the top right, and text appears on the slide: Shared Façade Runs]

 

The others start off as being externally exposed and then slowly we take them out of the equation and here’s one full set of runs for one of the apartments. You start with all fabric being exposed and then you have an adiabatic floor and then add an adiabatic ceiling and so on, right.

 

[Image changes to show a new slide show a table of data comparing the different apartments, and PC can be seen talking inset in the top right, and text appears on the slide: Shared Façade Adjustment Factors]

 

So, if we look at the base results, here’s the base results when all the fabric is exposed to the elements. You get heating and cooling outputs from NatHERS, you get the total number and then we remove all the shared, add in all the shared fabrics and then you can see the budgets drop and then as a factor of that number, what is this fraction? And you can see these are all sort of in that .54 average for the corner apartments and similarly for the middle apartments you can see that it sort of averages out at about 65% reduction from the Class 1 equivalent.

 

[Image changes to show a new slide, and PC can be seen talking inset in the top right, and text appears on the slide: Shared Fabric Adjustment, The Shared Fabric Adjustment Factor analysis shows that the energy budget for 7-star units, when compared to 7-star houses in Melbourne (or Sydney West), needs to be reduced by, Almost 60% for mid floor corner units, almost 70% for mid floor middle units]

 

So, we can see here what the outcomes are. Now if we want to have comparable fabric performance for Class 2, then we need to do some fairly hefty adjustments to the energy budget to get a similar thermal comfort type outcome, which is a proxy from the energy budget.

 

[Image changes to show a new slide, and PC can be seen talking inset in the top right, and text appears on the slide: Alternate Thermal Comfort Indicator, Needs research and testing, Potential candidates could be, A calibrated PMV values similar to JV3 in NCC Vol 1, or Limiting the difference between Mean Radiant and Mean Air temperatures in each zone]

 

Now, the second method is, really needs a bit more research and testing. You know, potential ways to do it might be that we have a calibrated predicted mean vote value, which is very similar to what they’re doing in JV3 or Volume 1. Another option might be that we actually test the difference between the radiant temperature and the air temperature in each zone of interest, really that’s what a good fabric does. It doesn’t allow the radiant temperature, what we feel, to be much worse than what the air temperature is.

 

[Image changes to show a new slide showing a floor plan of an apartment, and PC can be seen talking inset in the top right, and text appears on the slide: Apartments – L4 Detail]

 

If we did the second method, where we’re looking at comfort, then the thing that we want to be sure of is that every space of interest, so bedrooms, living rooms, dining rooms, kitchens, will get tested for that thermal comfort parameter and that it will meet that thermal comfort requirement.

 

[Image changes to show a new slide, and PC can be seen talking inset in the top right, and text appears on the slide: Whole Building Compliance, If thermal comfort can be assured for each of the living/dining/kitchen spaces, and the bedrooms, then energy budget per unit will be less relevant, the Total Building energy/GHG emissions would be important, And WHOLE BUILDING compliance, particularly mixed use buildings can be streamlined]

 

And then, if that’s the case, then the energy budget per unit becomes less relevant when we’re meeting the thermal comfort requirements, so you might as well check the energy, or the greenhouse emissions for the entire building, rather than just a unit, and if you took that route, then it will streamline compliance calculations at a whole building level, where you individually test the thermal comfort for each space.

 

[Image changes to show a new slide showing a diagram of an apartment block, and PC can be seen talking inset in the top right, and text appears on the slide: Whole Building Simulation]

 

We’re doing that already, in Volume 1 and then you can look at the whole building and what that does of course, is that, if you’ve got a building where you’ve got a bunch of apartments and then you’ve got some say, retail floors, or what is becoming even more common nowadays, we have retail and then apartments and then offices, then this method would certainly work. You can see these pink bits are shading that’s being represented. That’s a neighbouring building. Here’s another neighbouring building. We’re just representing it as shading planes. So, that kind of thing could be done quite easily. So, I’m going to leave it at that, and I’m hoping to have an interactive question-answer session with you guys shortly.

 

[Image changes to show a new slide, and PC can be seen talking inset in the top right, and text appears on the slide: Thank you]

 

Thanks.

 

[Image changes to show PC’s name on the screen and then the image changes to show Anthony talking to the camera on the main screen, and participants can be seen in the bar at the bottom of the screen]

 

Anthony Wright: Thanks PC. That’s fascinating and I’m really looking forward to the question-and-answer session at the end. We’ve got one last speaker now to play. I’m just going to pull up David Eckstein’s presentation and share that with you now.

 

[Image changes to show David Eckstein talking to the camera]

 

David Eckstein: Hello everyone. My name’s David Eckstein and I want to say thanks to the CSIRO for inviting me to present today. I’m looking forward to sharing some insights with a strong focus on compliance and I wish it wasn’t but it’s a pressing issue and a public interest issue. I’m presenting today from Gadigal Land, and I would like to acknowledge the Gadigal of the Eora Nation, the Traditional Custodians of this land, and I pay my respects to Elders, both past and present.

 

In a previous life I was part of the team that developed the BASIX scheme for the Department of Planning in New South Wales, which probably gives you a gauge for how long I’ve been working in this space, and I’ll share an insight on the early findings and audit work I did with, or for the Department about a decade ago. And before I move to the technical content of my presentation, I want to spend a few minutes providing some context. After I left the Department of Planning, round about 2007, I was invited, a few years later, 2013, to undertake a desktop audit of single dwellings and dual occupancies, looking at the documentation standards, and it was a fairly extensive compliance assessment scheme, ten councils and 100 DACCs but very informative at the time and it’s still available online. And the focus, like I say, at that time, was on single dwellings and dual occupancies with an intent to repeat for apartments, but that work didn’t proceed at the time. Look, it’s something of a systemic issue, isn’t it?

 

[Image continues to show David talking to the camera]

 

We analyse single dwellings abundantly and so often kick the can down the road for the apartment sector.  And this is true for policy, this is true for policy review, for real world performance analysis, energy end use etcetera and yet that’s the sector which perhaps deserves most focus right now. It’s, you know, it’s a significant growth sector. We can anticipate that many Australians will be buying, renting and occupying apartment dwellings into the future and obviously very, very hard to retrofit dwellings if they’re not built to standard. So, in terms of protecting the public interest and ensuring new buildings are built compliant with the regulatory standards of the time, this is absolutely a public interest matter and my experience over the past ten years is that we do have some serious and persistent compliance issues in this sector, and I hope to shine a bit more light on that today.

 

While I was at the City of Sydney, I was based in the team tasked with developing strategy and new policy, but I’ve always had a keen eye for how well current and past policy has delivered. I had a reputation as being a fence jumper, by which I mean in my early days, with the Department of Planning, when I was visiting regional and metropolitan areas to present and train people in the use of BASIX and the requirements of the scheme, I never missed an opportunity to walk around the back of a new development to have a look at what was really happening, and I’ve always enjoyed following through on policy delivery. Because I was the staff member deemed best able to assist development assessment planners at the City of Sydney regarding environmental performance claims made for new development  over a five-year period, I’ve looked probably at hundreds of Class 2 developments, not all super-tall skyrise, lots of low-rise Class 2 development, but certainly I’ve reviewed, you know, many, many, many sets of DA documentation for, for apartment development.

 

[Image continues to show David talking to the camera]

 

Spare a thought for those development assessment staff across the country, that they face some pretty brutal KPIs, largely focused on how quickly a planner approves or assesses a DA and recommends its approval or not. They’re dealing with complex development. Thermal performance compliance is just one item for them. It might be your lifeblood, it might be my fascination, but, you know, the planners are dealing with a wide array of planning, and urban amenity and public interest matters. So, much that we would love them to analyse every certificate that came their way, that’s not going to happen. It’s not going to happen in the future, so let’s be realistic about that.

 

They’ll never be expert in deep dive compliance assessment. Yes, as certifiers, they have a professional duty to do the best they can to protect the public interest, but they predominantly look at plans and not at the myriad of documents that sit behind those A1, A2 sets of rules. But I’m also able to spare a thought for the assessor community. I appreciate pressure that assessors are under from designers, an aside as I said to the assessors in the room today, I realise you often get asked to rate apartment development very late in the design process under tight time constraints, so you know I appreciate the pressures that you work under and the unrealistic timeframes that are probably put your way. But having said that, there are clear rules in the NatHERS technical notes about plan marking and that’s the focus of the rest of this presentation, because this is a public interest matter, and we know that retrofit of apartments is almost unheard of. So, we’ll go to the screenshare now and talk you through some of the content.

 

[Image changes to show a new slide showing a BASIX Audit Programme Report on the right, and David can be seen talking inset in the top right, and text appears on the slide: 2013 Compliance Audit – 100 Developments]

 

OK, I mentioned that the 2013 work I did for the Department of Planning at the time. The Department of Development might not sound like much, but ten councils and you know, rural, sort of regional, rural and, and metropolitan. Focus was on single dwellings, and I was looking at the documentation standards and development application and construction certificate stages. I appreciate, you know, in other jurisdictions you have slightly different language, building permits, et cetera. But I was looking at desktop documentation standards where buildings were constructed, and I focused on the standard of documentation for the thermal performance, energy and water requirements required to comply with the New South Wales regulatory settings. And look, the findings were quite encouraging. Documentation was generally fair to good. I’m going to give credit to the project homes section in particular here.

 

Their documentation standard was generally very good. They, they, you know, they’d work out a formula. They’d document with good diligence, and you know, I was really encouraged by the standard of documentation in that sector. In my report, which is actually still available online, a decade old and it’s still lurking there, I recommended that, you know, the Department establish a regular audit scheme and I even provided at that stage a SurveyMonkey method to do that. Light touch, but easily implemented and I also recommended, and we discussed, the team at the time discussed extending the Class 2 development and that was the intent. But as you all know, and as I indicated earlier, Class 2 development often gets booted down the road, and so, you know, it was another five years before a deep-dive audit was undertaken for Class 2 development and massive credit to the Victorian Building Authority on their work in the Energy Efficiency Audit Programme. Still looking to see the results. Maybe they’re out. Maybe, maybe they’re, they’re not out. I look forward to seeing those results and if, if they have been released, then please do let me know.

 

[Image changes to show a new slide, showing the 7 steps in the process of a NatHERS assessment, and David can be seen talking inset in the top right, and text appears on the slide: Intended process for NatHERS assessment]

 

So, this is a graphic I sometimes use the, I appreciate the certificate’s a little out of date, but don’t worry about that. The point that I’m making here, and that I use when I’m, I use for training certifiers, planners, et cetera, is that you know, the NatHERS assessment process involves a relationship between the architect and the design team in red on the left and NatHERS accredited assessors, thermal performance assessors on the right in blue and that little circle in the middle, you know, is, is a really important part of the process by which the NatHERS technical note makes clear the intent is that the plans are provided to assessors and that they’ll model in accordance with, in accordance with the, the plans and advise the designer regarding changes required to the specifications before the, the plans are stamped and the certificates released. So that’s the intent, that there is a dialogue there. Ideally, the design teams are marking up plans with some annotation to start with, but certainly there’s an expectation that, that closing schedules and insulation application et cetera will be provided from the design team’s side on instruction or in response to the assessors’ advice.

 

[Image changes to show a new slide showing aerial photos of a suburb and data alongside in a table, and David can be seen talking inset in the top right, and text appears on the slide: What Does Good Documentation look like?]

 

So, what does good documentation look like? I can appreciate you can’t see any detail on this plan cert, but this is an example of good documentation, so something that the City of Sydney would have received in the last year or two and obviously there’s a lot of text on the right there, but that’s, that’s driven by, in part by the BASIX regulations about plan marking or plan annotation for water efficiency, energy efficiency, but also thermal comfort items are described there. I’m just going to enlarge that for you. So, that’s an enlargement and what you can see here is that individual apartments are identified where different glazing standards apply. So, this is good practice, so for particular apartments there are different glazing standards and it’s itemised and that’s what’s required on the plan set for approval or for, before certificate of release. So, where individual apartments are treated differently, there need to be annotations on the plan set conveying that.

 

[Image changes to show a new slide showing a floor plan of an apartment, and a circle appears around some data to the right, and then the data is enlarged, and David can be seen talking inset in the top right, and text appears on the slide: Individual apartments are identified where different treatments apply]

 

Here's another example. Individual apartments with that specification block there which I’m going to enlarge here. The individual apartments itemised where they’re treated differently. This is not unreasonable to expect. This is, this is good documentation standard and meets the requirements of technical notes. Again, in this particular case, floor insulation itemised for particular units because there really was potential heat losses through ground floor and lower ground floor units.

 

[Image changes to show a new slide showing insulation treatment diagrams, and David can be seen talking inset in the top right, and text appears on the slide: Insulation treatments are marked up by the designer]

 

Another example here, the designer architect has indicated different thermal performance treatments for insulation for wall structures and floor structures there and you can see the annotation insulation BASIX requirements as per location and that is a rarity to see, that the designer has indicated thermal treatments.

 

[Image changes to show a new slide showing views of apartment blocks and diagrams of their floor plans with insulation and fans marked, and David can be seen talking inset in the top right, and text appears on the slide: Insulation and Fan mark-ups embedded in the plan set]

 

And one more example here, this particular development came to the city last year. A very large development, three large and very different looking buildings, some images on the bottom right and ceiling fans were needed to achieve thermal performance for this particular development, very well marked, different rooms and the insulation treatments also clearly marked with a colour scheme embedded in the plan set. This is what is expected. This shouldn’t be something that certifiers and regulatory authorities have to chase back for.

 

[Image changes to show the 7 step intended process for NatHERS assessment slide again, and David can be seen talking inset in the top right]

 

So, I guess what I want to say is that the issue is that dialogue that is supposed to occur between the architect design team and the thermal performance assessor, you know, I wish it happened and was clearly evident but I have to say that based on my experience with looking at a lot of DAs it’s clear that that’s not happening particularly well in the, in the contemporary scene.

 

[Image changes to show a new slide showing a Certificate check form on the right, and David can be seen talking inset in the top right, and text appears on the slide: Improvements to certificates helps, But no building certifiers are going to check all or many individual certificates]

 

So, now I want to show you a little bit of additional research we did at the City. Sorry, I want to just clarify that there have been changes to the NatHERS certificate regarding help, additional help notes for certifiers to use, pointing them to, to look for particular things and appreciate the improvements made to the certificates in the last couple of years, so that’s been great. But no building certifier, certifiers are going to check all or many individual certificates, that’s a reality. So, these sort of scenarios which still occur quite commonly where entrance doors to apartments, the entrance open to common areas are still being used for cross-ventilation modelling. It’s, it’s still there. We still see it and, you know, it’s a breach and you know, we know why it happens, because it means that you know, more logical and appropriate design measures are avoided through essentially a gaming mechanism. There’s no other way to call it that.

 

[Image changes to show a new slide showing a list of architects, and David can be seen talking inset in the top right, and text appears on the slide: Architects public position on sustainability, 1000+ Australian Architect signatories]

 

Look, remember that the architects, you know, much though, you know the, they might, I’ll give some real credit to you guys for being part of a body that’s signed up to the Australian Architects Declaration of Climate and Biodiversity, you know, thousands, there’s thousands of signatories to this document now, and in signing this document, you know, I believe that the practices, you know, listed are saying we care and we’re going to do something about it and, you know, most fundamental demonstration of doing something about climate change is to meet the compliance standards and mark up plans as required.

 

[Image changes to show a new slide showing a map of Sydney and surrounds on the right, and David can be seen talking inset in the top right, and text appears on the slide: Deep Dive, Focus – medium to high-rise developments, DAs lodged after 31 July 2020 (latest version of certificates), Documentation used, architectural plan set, a NatHERS summary certificate (provides access to modelling details), set of NatHERS stamped plans]

 

Look, the finishing slides just want to convey that, you know, I do have some pretty strong evidence to, to back, to back the content I presented today, you know, we knew at the City that these issues existed but we needed to be confident that they were, or you know, we needed to test whether these issues were systemic and I’m confident they are so at, at the City last year, we looked at 16 past year developments, looking particularly for larger developments, six stories and above, covering a total of 1,700 apartments, the range of development height or density, I guess, as indicated there, 4 to 62 stories, look 36% of the projects that were sourced or that we tried to source to do analysis on, we had to reject and not even include in the work we were doing, because the documentation was, was, it didn’t even allow us to start to do the analysis we wanted to do.

 

You know, the certificates were, well, you know, either certificates weren’t available, or the set of stamped plans weren’t available. I appreciate those are regular, regulatory side issues as much as they are applicant side issues, but, you know, it was a glaring signal of how weak things currently are in documentation compliance. So, what we did was we analysed architectural plans, NatHERS summary certificate and, and then we deep dived into the individual apartment certificates and I’m just going to give you a snapshot of the findings.

 

[Image changes to show a new slide showing a table on the right, and David can be seen talking inset in the top right, and text appears on the slide: Deep Dive, All reviewed developments had inconsistency in inputs, Casts doubt on credibility of the assessment, Casts doubt on dwelling’s thermal performance compliance, Erodes confidence in the scheme]

So, look this graphic here, and apologies that my image is crossing over the top a bit there, but in red is the degree to which plan sets working consistent with the NatHERS technical note 1.2 and the BASIX thermal comfort protocol and you can see that in a range of areas, compliances was very poor. Looking here at the exposure category and the thermal comfort assessors will know exactly what that is, you know, we have a high proportion of non-compliance in, in appropriate selection of exposure and that’s largely being done, driven, to imply stronger cross-ventilation opportunity for apartments than really might exist.

 

Look, over 50% of window openability claims were not validated by the plan set and were clearly in breach in places, you know, there’s clear building code standards for how far windows can be opened for child safety et cetera, in apartment buildings above ground floor and, and we identified you know, 50%, more than 50% of window openability claims were, so, were, or were erroneous, then if we look at the entrance doors, even with the change to the NatHERS certificate flagging that entrance doors should not be used for claimed cross-ventilation, except where, where valid, we still found it, even after that change was made to the certificate that 20% of the certificates we investigated still had dubious claims in them. So, look, all these findings, they cast doubt on the credibility of the assessment. They cast doubt on the dwelling’s thermal performance compliance, and they erode confidence in the scheme.

 

[Image changes to show a new slide, and David can be seen talking inset in the top right, and text appears on the slide: Summarising, There are clear rules – for modelling, for plan marking, Designers have an obligation to mark plans for thermal compliance, Compliance standards for apartment development are currently poor, The industry generally is failing the ‘public interest’ test, Scheme reputation may be eroded if standards do not improve]

 

So, summarising, look there are clear rules for modelling and for plan-marking. Designers have an obligation to mark plans for thermal compliance. They might have outsourced or thought they could outsource all that work to, to the specialist thermal comfort, thermal performance assessor, but the designers need to be reengaged in this space. Compliance standards for apartment development are currently poor and the industry is generally failing the public interest test here and the scheme itself, the reputation of the scheme can be eroded if standards do not improve. Thanks again for this opportunity to present this information to you. I’m, I look forward to hearing about further improvements to the scheme, in particular, around quality assurance and audit aspects of the scheme and I look forward to hearing your questions later on. Thank you very much. I’m going to stop sharing, and…

 

[Image changes to show PC on the main screen, and then the image changes to show Anthony talking to the camera and participants can be seen in the bar at the bottom of the screen]

 

Anthony Wright: Thank you, David, and thank you to all of our panel members. David, I don’t think you’ll have any argument from our audience, just knowing who’s usually out there about the need for energy raters and designers and architects to work more closely together and I wish we had a silver bullet for fixing that problem, rather than energy rating being treated as a hurdle compliance issue at the last minute in the design process.

 

While I wait for some questions to come in, oh there’s a few coming in now for your talk David, I’m going to direct a general question of my own to the panel. I might direct it to you PC first, perhaps and then Alex to follow up and we’ll see if Michael and David have anything to add after that, but I’m interested in the classification of Class 2 as a class [1:05:45] as a kind of general description, because it seems to cover an awful range of territory from very simple, perhaps two or three storey, predominantly walk up buildings with maybe one lift shared, through to the kind of buildings you’re talking about PC, that may include commercial space, office space, underground carparks, shared services and they’re a much more complicated beast altogether. Is the way we classify apartments a problem?

 

[Image changes to show PC talking to the camera and participants can be seen in the bar at the bottom of the screen]

 

PC Thomas: I’m not the right person to have a full resolution on that but I would say that, you know, smaller walk up, three-storey walk ups are particularly different from a 20-storey and the 200-apartment block, that is definitely the case. However, I think in either case the concepts that Alex and I have talked about apply, irrelevant of, you know, what the configurations are, and I do agree that there should probably be a simpler process for the smaller walk-ups to be tested compared to the bigger multistorey type apartments. Having other uses, like a mixed-use building, that simply means that under the code you, some part of the building has got a slightly different set of compliance requirements than others. I can see David’s put up his hand. He’s probably good to answer that I’d suggest.

 

[Image changes to show Anthony talking to the camera and participants can be seen in the bar at the bottom of the screen]

 

Anthony Wright: Sure, David. You are on mute, David, I’ll just unmute you.

 

[Image changes to show David talking to the camera and participants can be seen in the bar at the bottom of the screen]

 

David Eckstein: Is that OK? Can you hear me now? So, only, I was only going to add that you know in New South Wales they finally you know, bit the bullet and made the executive decision to remove these student accommodation, boarding house type Class 3 buildings from the NatHERS assessment process and the, the approval process in New South Wales now is expressly via JV, DTSJV3 if I’m right PC?

 

[Image changes to show PC talking to the camera and participants can be seen in the bar at the bottom of the screen]

 

PC Thomas: That’s right.

 

[Image changes to show David talking to the camera and participants can be seen in the bar at the bottom of the screen]

 

David Eckstein: And, and you know, that occurred and I, I’m on the outside so I don’t know the detail but that occurred partly because, in particular because the units are very small floor area and were increasingly hard to, just a, it was to do with the particular floor area factor that made it very hard to comply and what was happening is that people were literally just fudging to get the certificate and with design elements that were never going to be there so the Department made the right call in extracting that, that typology but that doesn’t remove the very significant slide that PC showed, which was, you know, why should a hotel and a boarding house have a different, you know, glazing performance standards from a dwelling because ultimately, people are living, you know, they’re living in those spaces, albeit temporarily and you know, you want to protect people from poor amenity and condensation and so, you know, it’s, it needs a fix that there is such a gap between the standards of, of those different, they’re different buildings, they operate differently, but they’re still places where people stay and sleep and rest and relax and you know, that’s called amenity and we should have effective protection for that without relying on high energy AC investments to, to fix it.

 

[Image changes to show Anthony talking to the camera and participants can be seen in the bar at the bottom of the screen]

 

Anthony Wright: Thanks David. Alex, did you want to offer an opinion?

 

[Image changes to show Alex talking to the camera and participants can be seen in the bar at the bottom of the screen]

 

Alex Zeller: Sure. So, qualities of building classifications aren’t really my speciality but my understanding is apartments, as they are, definitely should be able to be made to work. They’re not working as they should be. Class 2s, like apartments, are sort of in a funny place, because when you talk to someone about, who specialise in residential buildings, they often think about houses. If you talk to someone who specialises in commercial buildings, they say, they don’t think about apartments so much either. It’s sort of in this weird middle ground between the two where neither, you know, both sort of point the other as taking some responsibility and also since apartments of course have grown in importance over time, you know, a lot of historical codes, including NatHERS which is the Nationwide House Energy Rating Scheme, you know, they’ve initially based on houses and have been applied to apartments as they’ve grown in importance and maybe this, these are the sort of things we’re working through now.

 

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Anthony Wright: Good, thanks Alex. Michael, did you have anything to add?

 

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Michael Ambrose: Yeah. I’ll always add my two cents worth in. I suppose the main thing is that it sort of came up in what I was talking about with the other work that we’re doing, looking at common areas is, as we’re getting these particularly very large apartment buildings, NatHERS is only of course rating individual apartments within a much bigger, bigger building and as we’ve seen with some other work that has been done, the, as far as the energy consumption profile goes in these very large apartments buildings, often the vast, well not the vast majority, the majority of energy is going to go to the common areas which NatHERS doesn’t even consider, so I think particularly in these very large apartment buildings we, we have this disconnect between rating an individual apartment and 400 of those apartments all being individually rated and then what about the building that all these apartments are in and so that work that we’re doing with the New South Wales Government, trying to look at how does NABERS and NatHERS, how do we work all these ones, these systems together to get a much more consistent understanding of how the building as whole is performing?

 

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Anthony Wright: Thanks Michael. While I’ve got you, I’m going to ask you two questions at once that have come through from your presentation. The first is whether CSIRO can drill down into the data that you’ve presented to see the common features of lower-performing apartments and the second question, someone’s noted that New South Wales Class 2 ratings are the lowest, do you know why this is and is that anything to do with BASIX?

 

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Michael Ambrose: It, yes it probably is to do with the BASIX. We see that in Class 1s as well that they tend to rate a little bit lower in New South Wales because NatHERS is part of the BASIX process. We’ve got the heating and cooling caps that have to be achieved rather than a total cap. So, yeah, we, we I would surmise that the slightly lower rating that we see in New South Wales is because of BASIX. Can we drill down into individual apartments? Yes, yes, we can, just to see why they are performing worse than others. Yes. We do have the ability to do that. It is, it is a little bit time consuming to do it but the data, the data is there for us to look at. So, this is all a bit of a new area for us, looking at the apartments and trying to understand the apartment, how apartments are rated. With the datasets that we’ve got, and you know the presentation I gave was really, it came about because we, we were just curious about how this profiling looked and when we started looking at it, we thought actually this is, this is actually a very interesting bit of research that, that’s going on there. So, there’s areas that we’re going to be doing more work in.

 

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Anthony Wright. Thanks Michael. David.

 

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David Eckstein: Anthony, I’m not going to, I’m going to buy it because I have heard that so often for so long, and only one jurisdiction I know regulates in their own regulatory framework as opposed through a national, you know, a national framework that’s not hard wired into regulation, BASIX has mandatory plan locking and it means that any consent authority that is finding plans are not marked, they don’t have to spend very long. They just reference a part of the environmental planning assessment regulation and call the applicant to account.

 

So, all this talk, I’m going to say it very clearly, all this talk about New South Wales having a lower standard, I don’t work at the Department anymore but I’m going to tell you this is, this is, I’m going to tell you very straight. I’ve heard it for a decade. I’ve pointed to some very important compliance issues, so obsessing about half a star between one jurisdiction and another jurisdiction is a waste of time, because the scheme lacks the quality assurance that is required of it, and New South Wales has plan-locking hard wired into its regulatory framework and I don’t think many other jurisdictions do. So, I’m sorry, but because I hear it every time, this agonising over half a star between New South Wales and somewhere else, it’s irrelevant when compliance is so poor. Thank you.

 

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Anthony Wright: Thanks David.

 

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Michael Ambrose: Might I just say too, David, look I agree with you, that arguing over half a star is, it’s certainly something that we don’t, we don’t get too, you know, get fussed about that we see, that we see these differences and certainly I would applaud BASIX for they were, you know, they were, that was world-leading type stuff when that, that was introduced and I would love to see that type of much more holistic assessment of our buildings being undertaken.

 

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David Eckstein: And I’ll just say in other forums, people have heard me regularly speak about the, the disappointment in maintaining the quality of the system so, you know, the fact it’s 17 years old now, you know, it was pretty bloody innovative then and it disappoints me greatly that it isn’t, that it’s not maintained to the standard that it should and you know, we expect the high standard going forward with the new standards in the building, you know, that flow through from the NCC.

 

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Anthony Wright: Thank you. I will move on because we’ve got a lot of questions. I’ve got two here, that I will direct to you first Alex. PC, you might want to have a think about these while Alex is giving his answer. So, let me find them again now. They’re on tropical apartments and the different, the different kind of requirements around condensation and ventilation in tropical apartments, so the two questions that we’ve got are, and overheating, So, do you know of any overheating issues in apartments in warmer climates due to the penguin factor? And also, are there any issues in the tropics with cooling continuous ventilation, when it may be warm and moist outside, but cooler inside with air con? Are there any rules of thumb on this or is continuous ventilation always good throughout Australia? So, overheating and ventilation and condensation when it’s not in a cool climate?

 

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Alex Zeller: Sure, thanks Anthony, and yeah, they’re good points, so the presentation that I was giving was focused in cool, cooler climates of Australia, you know mostly, sort of the Melbourne climate. Yeah, and it was something that I considered putting in, but I took out at the time. The penguin factor, because NatHERS is annual, it’s very possible that you could have short periods of time where the building is, you know, excessively heat-stressed and it does, it can still get an OK NatHERS reading and yeah, the way that might come through is for, say, a west-facing apartment which for a few hours a day during summer it might get full-on sun which, yeah, very big heat stress on that apartment. So, yeah, so the overall metric of NatHERS which is overall energy use might not capture everything. It might not capture condensation. It might not capture instantaneous heat stress and I guess those considerations need to be made as to whether there’s a mechanism that should be used to regulate those matters.

 

On ventilation, and similar. So, the solution which I showed with, with the continuous exhaust ventilation which pulls outdoor air into the building, that is again, more of a cool climate ventilation approach. Ventilation would get, does get more complicated in humid climates. The recommendations in, you know, the best practice guides are to, if you’re continuously ventilating, to include some sort of dehumidification, whether that’s active dehumidification or whether that’s drawing through an energy recovery ventilation system which takes the humidity out of the air, but those systems are expensive, so it is more complicated, and you do need to have extra considerations in those humid climates. The simplest thing to, the simplest way to ventilate in a humid climate may be to have a ducted air conditioning system and to pull that outdoor air directly into that ducted air conditioning system and use that as the ventilation system and then that would dehumidify the air for you. That’s probably enough from me, I think.

 

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Anthony Wright: Thanks, Alex. PC, did you have anything to add to Alex’s answer?

 

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PC Thomas: I think Alex has got most of the main points right. There’s not much to add is there, a west-facing apartment in Darwin which is hot and humid would certainly cook, right, if you didn’t have shading. I, in fact, I’m at the Building Simulation Conference in Brisbane today and tomorrow, I’ve snuck out and about an hour ago before this meeting started, somebody asked me exactly the same question. What’s all the shading do when you’ve got 33^o air temperature, and I had to say, it is true, if the temperature outside is 33^o, the external shading may be less efficient or quiet but when the sun is shining on a particular façade, you do want to have solar shading at that time.

 

The second thing to probably think about is that if you have airtightness then you are, the leakage of warm moist air into your apartment is less, right, so you’re having to deal with less ingress of moist air and in those cases, you need air conditioning to dehumidify and typically we do that by condensing moisture out of a cooling coil. Now, if you use an ERV system which is what Alex was talking about, then obviously that energy use becomes less, because you’re exchanging air with what’s coming in, or exchanging moisture between the air stream coming in and going out and obviously that will reduce the amount of energy required. The third thing to maybe think about is that my wife, Professor Leena Thomas at UTS, she always calls me a technocentric person and she says that we should be able to possibly expand the, the comfort envelope that we can live with and maybe that’s something to think about as well, so I’m going to leave it at that.

 

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Anthony Wright: Thank you, PC, and there’s a couple of questions in here about overheating and so I’m going to, I will just do the usual plug for CSIRO and say Dong Chen is leading a three year study at the moment in all of the BCC climates, Building BCA climate zones to look at developing Australian comfort standards so we don’t have to keep hacking the European ones to try and match and perhaps that’s something that will come out of that, that we can tolerate a slightly wider comfort band and make all of this a little bit more realistic in Australia. I’m going to end with one final question, noting that we haven’t answered even half of the ones that came in unfortunately. I’m going to open this to the whole panel. We’ve got a question here just saying, are the panellists aware of any other countries that do energy efficiency in apartments well and if there are then what are they doing well? I’m happy for you guys to nominate yourselves as, feel free to answer that.

 

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PC: Well…

 

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Anthony Wright: No takers. PC.

 

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PC Thomas: I’ve got some experience of what happens in India which is probably one of the tropical countries that if we look at the southern part of India, particularly, is very tropical. I think it’s the same issues happening everywhere. There’s no real difference in that. But it does seem that even in places like India, air conditioning is now standard. You buy an apartment, it comes with a split system in there which probably talks about how poorly, well, the direction that we’re going to with it. Glazing systems are highly unregulated and I remember walking into a couple of demonstration units where the glazing was certainly less than 6mm. It was lucky if it was 3mm thick. So, you know, I don’t know if, I do think that in some of the European countries where it’s really cold, apartments do perform better, you do see double-glazed units everywhere, internal blinds, external shutters, for example, some of the refurbished apartments in Spain that I stayed in, and certainly seem to do quite well in that regard with an HRV in the kitchen cupboard, you know, so I’m going to leave it at that.

 

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Anthony Wright: Thanks PC. Did anyone else want to volunteer? Alex.

 

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Alex Zeller: I’ll jump in. Yeah, so I don’t know all the ins and outs necessarily of many international regulations, so I’m hesitant to say any, any you know, international regulation’s perfect. Different methods that are used in different countries do have different strengths and weaknesses. In Australia, with NatHERS, the strength is of course that it’s performance based, it’s, you know, people can responsibly design their, for their specific situation. For something like the penguin factor, other countries are more element-based so they might say there’s a, you know, a total cap on the u-value you should be using for your window and that, you know, means that, it addresses the comfort issues, it addresses the condensation issues a little bit more directly. So, there’s strengths and weaknesses to all the approaches.

 

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Anthony Wright: Good, thank you Alex. Michael, did you have anything to add?

 

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Michael Ambrose: Look, I’m not aware of how other countries do their apartments. I mean, I do, I agree with Alex that our approach of using thermal modelling for all our dwellings is relatively unusual around, around the world. There’s not too many other countries that require a full thermal model and of course, you know, it all becomes about where you then set the benchmarks for those performance results that you’re after. If you set them, set them fairly low you can do modelling to set them low and well, that’s how, it’s a sophisticated system but you still won’t get particularly well performing buildings if you set the marks too low.

 

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David Eckstein: I’ll just add that something I’ve heard frequently over the years is sort of clunkiness of, and no disrespect to anyone operating in the glazing industry online, but that, you know, some countries just have made that quantum shift to a standard high-performance glazing and the supply chains are sorted, et cetera. I think in Australia we’re patchy, you know we obviously rely on overseas products and which, you know, are purchased specifically for single projects et cetera and it’s pretty clunky and I reckon that, you know, we’ve been hearing a lot about you know, recovering our manufacturing and in, you know, securing our own control and independence rather than relying on fractured international supply chain issues and you know, glazing, you know, Australia step up.

 

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Michael Ambrose: I might just quickly chime in there, too. One of the things I’ve just, actually just recently looked at is the use of other default windows in NatHERS when assessments are done and particularly in apartments, we see a very high percentage of, of default windows being used in the assessment and I think that’s a reflection of, well it’s probably an issue with the custom window library that’s within the software, that does not really address the kinds of glazing systems that are going to typically be installed in the apartment buildings themselves so, it’s an interesting one, that it’s over 50% use default windows in Class 2s.

 

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Anthony Wright: Thanks, Michael. Oh, sorry Alex.

 

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Alex Zeller: Thanks, Anthony. Just to chime in one, I thought of one last point there, the fact that occurs in Australia and no other countries do, one effect of that, is actually it means it’s quite difficult to compare energy efficiency in Australia to other countries so, and I think this has a problem of masking just how inefficient some of our regulations in Australia are, for instance, like I was showing with that u-value graph in my presentation, if you just, u-value the windows on one of the most important energy efficiency factors in a home, whereas all the other countries have been a ceiling u-value and that has impacts for the manufacturing industry and the certainty for what they need to produce. It’s, you can’t really produce that in Australia and it’s, I mean you could, you probably see a reasonably big disconnect in what we do in Australia compared to overseas.

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David Eckstein: That’s a very pertinent point. Very pertinent point.

 

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Anthony Wright: With that, it’s, we’ve got one minute to spare. PC, I’m sure you have a session to go to and I certainly have another one so I am going to close it out and also there’s a risk of the pitchforks coming out with any mention of the windows libraries in NatHERS which I know have been on the cards to be fixed for a decade and I’m sure will be very, very soon. We’ve, I’m conscious that there’s about 25 questions in there that we haven’t got around to yet. My typical practice with these webinars is to try and answer them from CSIRO’s perspective and seek the input of our panellists on the answers to those questions. So, do get your last minute questions in.

 

Panellists, I will send that by and if you do have the time to have a look and just make sure I haven’t misrepresented anything or said anything silly, I would appreciate it, and we generally publish those with the recordings of the webinar. So, if you haven’t had your questions answered today, make sure they’re in there and we’ll do our best to answer them in writing with the recording of the webinar. Keep an eye out for that, Lachlan will send around a notice once that’s up there and it goes on the ahd.csiro.au website under webinars. But, with that I’ll close it out. Thank you once again to our fine panellists. I really appreciate the time and effort you’ve put into your presentations, and I know our audience really appreciates it. David, did you want to have…?

 

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David Eckstein: No, just thank you. Thank you for the opportunity.

 

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Anthony Wright: You’re most welcome. I will hang around for 30 seconds or so more in order to receive the last of the questions as they come in, but you’re all welcome to drop out of the call now. Thanks for your time and I’ll talk to you all again soon, I’m sure. Thank you.