Summary

Heating and cooling load caps remain one of the most misunderstood parts of NatHERS compliance, six years after they were introduced. In this episode the team works through what the caps actually are, why a star rating on its own was never enough, and why the floor type of a home changes the targets it must hit.

The discussion then turns to the part of the rules that still divides assessors: the phrase "the floor type of the lowest living area". The ABCB Heating and Cooling Load Limits Standard defers that definition to NatHERS, the NatHERS Universal Certificate words it differently again, and the software words it differently a third time. The team pulls the definition apart clause by clause, including where the commas fall, and works through a reverse-living house to test how far the interpretation stretches — down to whether an enclosed stairwell above a garage decides which set of caps applies to the whole dwelling.

The episode closes on why this matters beyond paperwork. The team describes a builder whose previous assessments had never checked the cooling load at all, so an entire portfolio of homes was non-compliant without anyone noticing, and discusses the occupant safety consequences when a dwelling overheats.

In this episode

• 0:50What a heating load and a cooling load actually measure

• 1:45Why separate caps were introduced on top of the star rating

• 3:11The three metrics every dwelling must satisfy, and the New South Wales exception

• 3:53Where the caps came from: Victorian apartments before NCC 2019

• 4:50How the limits were derived: 170,000 homes, percentiles and outliers

• 7:58Slab on ground versus suspended timber: thermal mass and ground coupling

• 10:06Why floor type changes the caps when the total load stays the same

• 15:26How the floor type is selected in NatHERS software

• 16:19"The floor type of the lowest living area" and where the definition breaks down

• 18:35Three documents, three different wordings

• 20:35The comma debate: living area, or any conditioned area?

• 24:07Worked example: a reverse-living house with a garage below

• 26:03Does a stairwell decide the caps for the whole dwelling?

• 30:10Why "living" is the wrong word and "conditioned" is the right one

• 35:33The builder whose cooling loads had never been checked

• 37:14Occupant safety, heat stress and climate safe rooms

• 40:30Summary and the team's interpretation

Key points

There are three metrics, not one

A dwelling must satisfy the heating load cap, the cooling load cap, and the total load, which is the two added together and corresponds to the star rating. Everybody focuses on the total, but failing either of the other two means the home does not comply. The exception is New South Wales under BASIX, in NatHERS climate zones 9, 10 and 11.

The caps exist because a star rating alone can be gamed

In a cool climate a dwelling could be designed to score well overall by performing strongly in winter — heavy insulation, good orientation — while nobody addressed shading, airflow or ventilation. The score looks acceptable on paper and the house bakes between December and February. The separate limits sit over the top of the star rating so that one cannot be traded away against the other.

Floor type changes the target, not just the result

A suspended timber floor has air moving beneath it and no coupling to the ground, so a stable temperature is harder to hold. A slab on ground carries thermal mass and is either coupled to the ground or deliberately decoupled with insulation. The two behave so differently through winter heat loss and summer heat gain that a single set of limits could not fairly serve both — and the same construction that penalises a dwelling in Melbourne may assist it in Queensland, where letting heat escape through the floor is an advantage.

The definition is genuinely ambiguous, and the team says so

Clause 2.3 of the ABCB standard sets the limits by "the floor type of the lowest living area". The glossary then defines living area as "a conditioned area of a dwelling, including a living, kitchen and/or kitchen living zone", as defined by NatHERS. Read with the commas as written, the operative phrase is simply a conditioned area of a dwelling, and the zone types that follow are examples rather than an exhaustive list. Meanwhile the Universal Certificate refers to the lowest conditioned area, and FirstRate5 refers to the floor type of the lowest conditioned zone. Neither "living" nor "lowest" is defined tightly enough to remove interpretation.

Taken to its logical end, a stairwell can decide the caps

Working through a reverse-living house — garage, study, laundry and stairwell downstairs, living areas above — the team strips out each ground floor space in turn. NatHERS treats a stairwell as a conditioned daytime zone, and it remains one even if a door is fitted at the top. On the reading that the standard means any conditioned area, that stairwell sets the floor type used to select the caps for the entire dwelling. Where a project sits in this grey area, the team's advice is to model it both ways and raise it with your Assessor Accrediting Organisation.

Whatever you decide, apply it consistently

An interpretation that helps a project in a tropical climate must also be applied where it hurts, in a cold one. The team's position is that the rule should be read as any conditioned area of the dwelling, that the word "living" causes more problems than it solves, and that the ABCB could remove the ambiguity by referring plainly to a conditioned space — or by pointing to the far fuller list of zone types already published in Appendix 1 of the NatHERS Technical Note.

This is a real compliance risk, not a theoretical one

The team describes taking over work from a builder producing between fifty and one hundred homes a year and finding cooling load failures every few houses. Reviewing the previous assessor's reports showed the cooling load had not been considered at all. Under NCC 2019, before the caps appeared on the Universal Certificate, that could go unnoticed for years across an entire portfolio. The consequence is not administrative: an overheating dwelling carries a genuine risk of heat exhaustion and heat stroke for the people living in it.

Documents referenced

• ABCB NatHERS Heating and Cooling Load Limits StandardThe separate standard the NCC calls up, containing the limits and the definitions discussed in this episode.

• NatHERS publicationsTechnical Note, assessor handbook and scheme guidance material.

• National Construction CodeAustralian Building Codes Board — the code itself, and the Housing Provisions referenced throughout.

Transcript

Lightly edited for readability. Hesitations and repetition have been removed and technical terms corrected; the substance is unchanged.

0:06Welcome to The Rating Room, the podcast where we unpack everything. I am Brian Haines, and alongside me are my co-hosts Matthew Graham and Andrew Hooper. We dive into the technical, the practical, and sometimes the controversial side of residential energy efficiency assessments in Australia. If you are working in the field of NatHERS, or just trying to navigate the space, this is where the ratings get real. Let us get into it.

0:30Tonight we are discussing heating and cooling loads — capped heating and cooling loads, which were introduced into NCC 2019. We had a twelve month grace period, so we all started that in 2020.

0:50I thought I would first start with what a heating and cooling load actually is, so we can understand the caps. On a cold winter's day your heater has to work hard to keep your living room warm. The total amount of energy that needs to be pumped in over the whole year just to keep things comfortable — that is your heating load. The same works for summer: the amount of energy your air conditioner needs to pull out of the house is your cooling load. Both are measured in megajoules per square metre per annum, which is essentially a unit that tells you how much energy is needed relative to the size of the house.

1:45So what are we doing with those loads, and why is there a cap? Why do we need separate load limits on top of what we already had, which was a star rating? In theory you could design a house that scored really well on a star rating. In a cool climate you could make it great in winter — lots of insulation, great orientation — but then summer rolls around and the house bakes, because nobody thought about shading or airflow or ventilation. The overall score looks fine on paper, but the house is pretty miserable between December and February. That is why the rules were introduced: to have separate heating and cooling load limits that sit over the top of the star rating, so you cannot pass on one and ignore the other. You have to pass both. And it is not just passing both of those — you also need to independently pass on the total as well.

3:11The total load relates to the star rating itself, as per the NatHERS star bands. But then we have the heating and cooling loads, which are separate metrics that need to be adhered to. You need to be below those specific caps for each climate zone, and the total load is the heating load and the cooling load added together. We need to meet each of the three metrics or the house does not comply. Correct — except in New South Wales under BASIX, in NatHERS climate zones 9, 10 and 11.

3:53I might backtrack a little on that too. It actually came in before NCC 2019, because it came in for apartments in Victoria a couple of years earlier. The apartments on the north and the west were absolutely stinking hot. Everything complied, but these were rotten. So the Victorian government brought them in under the planning schemes for apartments, Class 2, and then the ABCB and the NCC followed up and mandated it in all homes and apartments. I remember the ESD requirements, and the cooling load was something like 21 megajoules per square metre for the City of Melbourne — metropolitan Melbourne. Well, not quite metropolitan Melbourne, because outside it there was nothing.

4:50From my understanding, the development behind all these capped heating and cooling loads was to stop hot boxes in summer, and let us say cold boxes in winter. Do you know how it was all developed — what study was done, the calculations behind it?

5:10I will not pretend to know the detail of it. The documents are online and you can go back and read them: the requests made before the study was done, what the study involved, a couple of different study papers, and then the regulatory impact statement that came from it. The gist of it, off the top of my head, was something like 170,000 homes. Their modelling results were taken from the Australian Housing Data Portal, looked at across different climate zones, and they came up with percentiles for what the limits were. Part of the study also involved looking at a number of set designs in set locations, in different orientations and possibly different materials. It was a great deal of research to arrive at the figures they arrived at.

6:30I remember looking at the graphs in the regulatory impact statement — all the dots centring as they went, and then outliers scooting off out to oblivion. Those were around the 5th or 95th percentile, and they were the ones discounted. They are the outliers, the ones that obviously do not get picked up, and that is the exact reason for doing it that way. It does make sense when you think about it. I did look at the study not too long ago: the request was made to make sure that a house fell into a comfortable zone. That was the defining feature initially.

7:24We now transition into the floor type — whether it is a suspended floor or a concrete floor — which drove it. I do not remember whether that was part of the original study, but I think it had an influence. I know it is a big factor in how you select what those capped heating and cooling loads are going to be, but I do not know what the reasoning behind that was. The houses were a mixture of both, with different floor construction: concrete slab on ground and suspended timber floor.

7:58In terms of general modelling of energy within a building, we know a concrete slab is going to have thermal mass and that will have an effect. We know a timber floor is going to be different. It does not have the thermal mass, it is off the ground, it is not coupled. That is really about the way the energy flows.

8:30That is all well and good with the star rating itself, but why does the selection of the floor type — whether it is suspended or coupled to the ground — actually make a difference to the specific heating and cooling load requirements we need to adhere to? I still cannot wrap my head around why it matters.

9:02There are still houses built with either concrete slab on ground, or a suspended timber floor, or a combination of both. With a suspended timber floor you have air movement underneath, so that is going to make it a lot more difficult to achieve a stable temperature. Whereas with a concrete slab on ground you do not have that: you have either ground coupling, or it could be decoupled with some insulation. The winter heat loss and the summer heat gain are different. They perform differently, therefore you have to have different heating and cooling load limits to accommodate fundamentally different floor construction — especially as the floor construction is a fairly significant component of an overall rating.

10:06You have the same total load. It does not matter whether you are suspended or concrete slab on ground, it is still the same total load. So why would it make a difference what the capped heating and cooling loads are, depending on what floor system you select? Am I making sense at all?

10:32You are. I am just trying to think of what the answer is. If we took the same house and optimised it — let us say we started with a concrete slab and optimised that to seven stars — and then we put it on a timber floor, we are not going to hit seven stars, depending on the climate zone. In Melbourne, a timber floor will be harder to get to seven stars to start with, because you are losing that coupling, you are losing that mass. So do you want to be penalised by saying you should have the same outcomes for heating in Melbourne for both a slab and a timber floor, if a timber floor is harder to hit the target? Conversely, if you are in Queensland a timber floor might be better, because you can let that heat escape through the floor, where the concrete would retain it — so it would be harder to achieve compliance with a slab in Queensland.

11:52You do a lot of Queensland work. You always have issues with cooling loads, but generally it is quite easy to mitigate that with ceiling fans and light colours and those sorts of things. To be perfectly honest I do not know whether that scale inverts as you head further up the country — whether it becomes easier or harder to comply with a suspended timber subfloor depending on whether you are in Victoria or Queensland. Do you know where those numbers invert? That would make sense with what you were just saying. I do not do enough work out of Victoria to have confidence in answering that. Mine is predominantly in a cooling climate. I would think that at the two extremes you have two different situations, and in the centre it is probably having less of an effect.

13:04If we get back to the original question, I think what Andrew is saying is that the expected level of thermal comfort is still the same whether you are building with a suspended timber floor or a concrete floor. You are still expecting seven stars as your minimum level of thermal comfort. But it is more difficult, and if you look at the heating and cooling loads of a suspended timber floor against a concrete one, they are going to be quite different. They are going to have a different balance of heating and cooling.

13:48So we are basically saying that because the systems are so dramatically different in their makeup of those two specific metrics, you could not have a one-size-fits-all for the different floor types, because they behave so completely differently.

14:06And that is also where we have a combination of the two as well. Some projects are not strictly built with either just a suspended timber floor or just a concrete slab on ground.

14:23If you go back to the original studies, once they got past the Australian Housing Data Portal they used specific houses and modelled them in different climate zones. Certain designs performed better in one place than another, and that increased the data they had to work with. For instance there was a Queenslander type building, where it was just a garage and service rooms downstairs, that performed better in a hotter or tropical climate than it did in a southern environment.

15:26For anybody following along at home who does not do NatHERS assessments, do you want to cover how this is actually selected within the software?

15:46The NCC calls it up, but it is not actually in the NCC. It just says that under the specification you have to comply with the Heating and Cooling Load Limits Standard, which is a separate document you download from the ABCB, and that sets out all the limits. The rest of the standard talks about the type of floor, and it does determine the living space. "The lowest living area" is the wording it uses — the lowest living area of the house. If it is on a concrete slab you use one set of figures; if it is on a suspended floor you use a second set. And the glossary defines it.

16:55This is where it gets interesting. You get the floor type of the lowest living area, which is a phrase that carries a lot of weight and has two different meanings. It is quite difficult to find documentation that supports this when you delve deeper. How about we say that it is impossible to find a document that supports this?

17:24We should cover what the standard glossary includes, because there is an entry for living area. Looking again at the ABCB NatHERS Heating and Cooling Load Limits Standard, clause 2.3 says the limits are determined by the floor type of the lowest living area, and the glossary defines living area as a conditioned area of a dwelling, including a living, kitchen and/or kitchen living zone.

18:05Which is a NatHERS definition. It is really just deferring to the NatHERS software documentation for that definition. The key phrase there is "as defined by NatHERS", and it is a little incomplete at face value. It is not fully resolved in this document on its own.

18:35Then when you look at other documentation — for example the Universal Certificate — it clearly defines it as the lowest conditioned area, which is something different again. And from a FirstRate5 point of view, it says the floor type of the lowest conditioned zone. So we are talking about zones, we are talking about conditioned areas, and we are talking about living areas.

19:09Fundamentally we also have a problem with "lowest". Not only is the type of the zone in question, "lowest" is not clearly defined either. The additional information does say, typically, the ground floor of the home — but if there is a garage under it, you might find otherwise. That is just one example. To me it starts to say that conditioned is your living space. Forget "living zone" as a zone in NatHERS; a living space is where people live. That can include bedrooms, studies, lounge rooms or whatever.

20:04Read that definition again. "The floor type of the lowest living area", and the glossary defines living area as a conditioned area of a dwelling, including a living, kitchen and/or kitchen living zone — very limited choices there, as defined by NatHERS. That is in the ABCB documentation, which is probably pulled from NatHERS.

20:35I am going to be argumentative here and ask where the commas are in that. A conditioned area of a dwelling, comma, which includes these zones, comma, as defined by NatHERS. You have to love these commas. If you take out the "including", you end up with a conditioned zone as defined by NatHERS. So is a daytime zone a conditioned zone as defined by NatHERS? The word "including" is not exclusive — it is not saying exclusively living, kitchen, kitchen living. It is saying including, so it could be anything.

21:25That is what makes it really difficult. Why do they not say including bedroom, including everything else? To me those commas are detrimental to that statement. If you work between the commas and take out the "it could include", you are left with a statement saying it is all conditioned zones. I agree with you: a conditioned area of a dwelling, full stop. If it just said that, you are right — the rest of it could have gone. And for me that goes to the intent.

22:08It is probably not what we are used to in NatHERS. We are used to more formal or prescriptive definitions, and this one is lacking that. "Lowest living area" is an incomplete definition that points offstage, and then another key word that has no definition at all. That combination is not good for consistency. NatHERS as a scheme strives not just for accuracy but for consistency, and this one leaves too much room for interpretation between assessors.

23:08This extends further to the word "living", which can mean so much. The NatHERS Technical Note and the handbook talk about a living zone separately from a living space. Both terms are used — an outdoor living space is not a living zone. Finding that line between a living zone and a space that you live in is what makes it difficult. Under the rules you get one kitchen living, you are limited to two living zones, and other zones after that are still considered conditioned zones — they could be living zones, but they become daytime zones. That opens it up more broadly to considering the conditioned building envelope.

24:07That leads to my next question. Say you have a reverse-living house. On the ground floor there is a garage, a study, a rumpus room, a laundry and a stairwell. You walk upstairs and that is where all the living areas are — the kitchen, the living, the bedrooms. You also have more than two living zones upstairs, so your living zone on the ground floor has to be a daytime conditioned zone. Assuming that is a conditioned zone, that would mean the ground floor is what we use when we select our heating and cooling loads. We are all good there, because there is a conditioned zone on the ground floor. That is following the intent of the conditioned building envelope.

25:19Now let us take out that living area that is a daytime conditioned zone, because we have run out of living zones in the house. Now we are back to a study, a laundry and a stairwell. Are we still good with that being the lowest conditioned zone? Yes — you have a study, and people are going to be using that in some function for a length of time.

25:50Let us take out the study. Now we are left with a garage, a laundry and a stairwell. The stairwell is still a daytime conditioned zone. Are we still saying that the ground floor is the defining factor for the heating and cooling loads?

26:09I go back to the house I mentioned before, in the study, that had only a garage and service rooms downstairs. I do not recall the floor plan exactly, or whether there was a staircase going from the ground floor to the top floor. So does the staircase alone constitute a conditioned space — a living space by virtue of being conditioned? That is right. But is it a living space, or is it a conditioned area? What are we really saying?

26:45I will go beyond that question and ask what the staircase is connected to. Is there an entry down there? Is there outside air movement coming into an entry space and up the stairs, or is it just connected to a laundry and a garage? And then I want to go to the double height void zone, which starts to add the conditioning of the upper level to the lower one.

27:20Let us take both scenarios. Say the staircase just goes up into the kitchen, living and dining zone — we see that a lot, it is not out of the ordinary. Is there glazing? Let us say there is no glazing in the stairwell itself; say it is cut into a hill. You walk up the stairs and that is where all the living rooms are. And it is a suspended timber subfloor on the first floor, with concrete slab on ground below because that is where the garage is.

28:08If you read this the way Andrew was suggesting, depending on where you put all the commas — as being a conditioned area of a dwelling — then it is conditioned as defined by NatHERS. NatHERS defines the stairwell as conditioned. It is conditioned.

28:27So what happens if I put a door on top of the stairwell, enclosing it? Nothing changes. It is still defined by NatHERS as a conditioned space, and it would still be a daytime zone. That is my interpretation.

28:47Maybe this is an example where you would model it one way, model it the other way, and go to your Assessor Accrediting Organisation and have a chat with them. Is that really necessary? It is circulation space, and circulation space will be daytime. For me it is probably not necessary, but you are asking a question where you clearly have something in mind — that the bulk of the living, where people are actually living rather than circulating, is on the upper level, so why not?

29:15You would have to be consistent as well. If you are going to do that in a tropical climate where it might be better, you are going to have to do it in a colder climate where it is going to be really bad. Your rules have to be consistent no matter where you are doing the assessment. That is where you keep coming back to the definition of living as defined by NatHERS, and saying that is my rule and I am going to be consistent with it.

29:52So it is not really a living area. It is a conditioned space. That is the way I interpret it — a living space is a conditioned space as defined by NatHERS. We have to stop saying living area. We have to say space. "Living" is too broad. Possibly to fix this up, refer to a conditioned space and then list examples. And it would be good if one of those conditioned zones was a nighttime zone, so they were not all daytime, because nighttime still loses me too.

30:28Nighttime is still conditioned. All three examples they use — living, kitchen, kitchen living — are daytime. You will not be able to have a nighttime zone on a ground floor without having some other type of zone attached to it, which would form part of the conditions. So you could not have a nighttime zone on its own. It is just a conditioned area of the dwelling, and here are some examples.

31:05If you were to rewrite it, instead of "a conditioned area of the dwelling including a living, kitchen and/or kitchen living zone" — we do not actually have a kitchen zone strictly on its own. The kitchen on its own is a kitchen living. It is a zone that does not really exist, because a kitchen-only zone is not common these days in design. So just get rid of the examples and have it as a conditioned area of a dwelling. And if you must have examples, include a range of them. There is a stack of examples in the Technical Note — a glossary of about twenty-five or thirty in Appendix 1. It is quite extensive. That is why it is really difficult when you cherry-pick a few. It just makes things worse.

32:05Even a living zone is just a temperature profile, ultimately — an occupancy profile, temperature, time and occupancy. It varies. It is as conditioned as anything else; it just might have different times when people are there. Do you think it is based on that occupancy profile? A doored-off stairwell is certainly going to have a very different occupancy profile than a kitchen living zone. I do not think it is as complex as that. I think it is just looking at the conditioned building envelope, which is principally what we are doing in NatHERS. I am not sure we can read anything more into it.

33:04So who is ringing up the ABCB to get this sorted out? Look, this has been out for six years. I do not think it is going to change as such — but clarification would be good. I like black and white. I like things laid out precisely. There are new technical notes and guidance notes coming out; maybe there will be more information in there one day. I would like that. I hate grey zones. I hate looking at things and saying, well, I could do this or I could do that. I want answers.

33:48What about an NCC 2025 heating and cooling load document from the ABCB where they just fix this up, along with a couple of other things? It could be mentioned in the Heating and Cooling Load Limits Standard — that is probably where it belongs. Although it does not need to be, because it is "as defined by NatHERS", so the ABCB's hands are tied. Say it in the glossary for living, then.

34:20The standard glossary does have an entry for living area, and if Andrew is right it defers to the NatHERS software documentation, which would then define it. I like black and white as well, but consistency would be the driving reason to clarify this. You do not want the interpretation, you do not want the grey. You might interpret it one way, I might interpret it another, and Brian might go another way again. It literally says "as defined by NatHERS".

35:13So take the ABCB out of the equation — they have said what they are going to say. In a utopia, I would like NatHERS to come back and say the caps apply in these exact situations. Move on, nothing to see.

35:33This was introduced in 2020, so it is six years old now. Two or three years ago we were dealing with a builder doing fifty to one hundred houses a year — half volume, half custom, lots of glass, lots of return walls, lots of intricate geometry. When we were assessing them, pretty consistently, every handful of houses we were having major cooling load issues. To counteract that in a colder Victorian climate there is not a lot you can do: low SHGC glazing is the main lever, plus fans and opening windows.

36:27They asked why this was always happening, because we had just taken over the work. We got hold of some of the previous NatHERS assessments that had been done for them, and the cooling load had not been looked at at all. This was under NCC 2019, before the heating and cooling load caps were written on the Universal Certificate. So you still had four or five years where you could have been doing NCC 2019 work and not complying with the cooling load caps in Victoria, and nobody would have been the wiser if they did not actually look at it. All of these energy reports had been done, and none of them comply.

37:14That is a pretty egregious issue, especially when you consider it could seriously affect an occupant — heat exhaustion, heat stroke. There is a lot of research now about climate safe rooms. Is your total envelope too cold, so that there is a room you can go to and take shelter in? Is your environment too hot, so that there is a room you can shelter in? This is being recognised more and more, beyond the heating and cooling caps, in existing homes as well. It is ludicrous not to have looked at the caps when they existed. You could potentially put someone's life in danger.

38:22This is another example of why we need to talk about these things, so that people understand what they are looking at and know what to look out for. At some point it might be good for us to go through a certificate piece by piece and talk about what to look for, because there is not enough of that auditing process happening at building permit stage, during construction, or post construction to make sure everything aligns with the NatHERS certificate.

38:53The NatHERS software does show you whether you are complying with the heating and cooling load limits — it does for 2022, but not for 2019. It is there, but in small numbers, and it is just not obvious. The assessor is also usually prompted when creating a NatHERS certificate, reminded that their assessment needs to comply with the heating and cooling load limits. The software presents it as green is good, red is bad, and when you upload there is a reminder that says, by the way, make sure you are checking that it complies.

39:50The trouble with prompts — and I am guilty of it — is that you just click okay. You are so used to seeing them that you tap through. You need something flashing: hey, this does not work. It is a little more obvious in some NatHERS software tools than others. And there are instances, with renovations and extensions, where it would not apply or different metrics apply, so when you select whether it is a new house or a renovation, maybe that could be a hard stop.

40:30Let us summarise what we have covered, for anybody who is not doing NatHERS assessments but wants to look at the certificates and work out how we have come to the conclusions we have. There are three metrics we need to comply with: the heating load, the cooling load and the total load. Everybody focuses on the total load, which is the star rating, but there are those two other metrics. The heating load and cooling load differ depending on the climate zone of the project — there are sixty-nine different NatHERS climate zones with different heating and cooling loads — and also on the lowest floor type of the project, which is selectable within the software. What that conditioning is, is any conditioned area in the dwelling. We are pretty certain that it is any conditioned area in the dwelling, and whatever the lowest conditioned area is, that is what you are going to select in the software.

41:38That is our interpretation today. Works for me.

41:45That wraps up this episode of The Rating Room. Thanks for joining myself, Matthew and Andrew as we uncovered another corner of the NatHERS world. Your thoughts, comments and questions are important to us, so leave a message on the NatHERS Assessor Network Facebook page or leave a comment on the video below. And until next time, keep rating.