#28 - Part 1 | Pretty Isn’t Enough: Building Physics That Actually Matter with Michael Kingsland

Jess Kismet (00:00)
Hello and welcome to The Building Sciology Poddie where we talk about better buildings to live and breathe in. My name is Jess Kismet and today I am joined by Michael Kingsland from Laros Technologies in Canberra.

Michael (00:08)
Yeah, yeah. Do you have a list for

Jess Kismet (00:11)
Laros

Michael (00:11)
them?

Jess Kismet (00:12)
are a retailer and they are also a consultancy sort of similar to Climashore but bigger. They sell windows, mechanical ventilation systems, they consult on passive house, air tightness, thermal bridging and all that good stuff. Michael works with builders, designers and other consultants to push the envelope and ensure best practice outcomes. We spent a couple of days together in Auckland in the beginning of the year at the Pro Clima Install Training with some other Pro Clima partners in Australia.

and hearing him in the classroom explaining a few things to the room, I decided I definitely wanted to have him on the show. You're a super smart guy, Michael, and I'm pleased to have you. So thank you for joining me.

Michael (00:48)
Thanks

a lot also for the intro. Yep, excited to be here. Thanks.

Jess Kismet (00:53)
Awesome.

So could you please start off with the background on who you are and why you started LAROS or how LAROS came to be for you?

Michael (01:02)
Yeah, so I didn't actually start LAROS. It's been around for a while since 2009. And the name kind of has it in it to some degree. So originally LAROS started out as solar business. if you... Letters is an anagram for solar. LAROS, solar. Makes kind of sense if you stram the letters around. Yeah. And we didn't do any building related stuff at all to start with, so just solar. So the guys who actually started it were kind of from solar researchers from the Australian National University here in Canberra at the Solar Thermal Group.

Jess Kismet (01:15)
That's a little fun fact, Laros,

Michael (01:29)
And that's kind of how I kind of came into that as well. I was working my PhD about 15, 16 years later before the guys, after the guys had the Pesado Larros and met Andreas, who was one of the founders. they came in and visited every now and then. Yeah. Reiko Pacific and KLH. So he still does the... Yeah. So he does facade. So Timbers facades, Timbers skylights. And...

Jess Kismet (01:43)
Is Andreas now Rayco Skylights?

Reco Pacific, yeah, we've been dealing with him on a couple of our Passive House projects. I saw his name and I was like, I know that name. Yeah.

Michael (01:55)
Exactly. also, CLT, import CLT, people are familiar with that. So yeah, kind of the, so the start of it was originally solar. People were passionate about, you know, renewable energy, that kind of things. And, and I joined in 2012. And we kind of were supplying the first large scale solar systems in Canberra. So 100, 200 kilowatt kind of size. And, you know, there were lots of support kind of programs coming in around the time as well. The government supported solar, of course.

And we kind of what we did, we designed the systems and we supplied the products and we didn't install ourselves. So we had kind of subcontracted installers and with more support from the government, we found more and more, we actually started competing with our own installers. So they kind of learned from us how to design systems and where the products came from and things like that. And just kind of counter office and like, because we, the install kind of part of the whole project was so large.

Jess Kismet (02:44)
Interesting.

Michael (02:51)
that we found it harder and harder to compete with that. And incidentally at the same time, so that Andreas, his background from Switzerland originally, actually used to be the director of the Swiss Institute of certifying and testing high-performance building products. So that the Swiss have a similar kind of scheme compared to Passive House. called Minagi in Switzerland and it's very, very similar. So part of his passion was already always from that.

Jess Kismet (03:15)
Yeah, right.

Michael (03:18)
high-performance building side, he knew the bleeding edge of products and what's kind really required to make buildings work. So it was kind of one of our advantages and made it easy then to shift into the high-performance building space. Myself, I started at Laros, we did Solar, we started importing products from Europe. We were already importing products and I wanted to improve my own building. And I thought like, well, let's look for Windows first. And we started talking about importing Windows and then straight away we had like three, four.

Jess Kismet (03:42)
your own house.

Michael (03:46)
other people, what you bringing Windows in from Germany? I want them as well and me as well. then, you know, things fall off that way and importing, we're importing business. So we knew how that works. It was easy to bring in container loads of stuff and kind of kickstarted that whole side of the business.

Jess Kismet (03:50)
Yeah.

Awesome, so that was your own house you wanted those windows for?

Michael (04:02)
Yeah, so my dream

was originally to make my own windows. I kind of like doing hands-on stuff as well. So I like working with timber. So I thought I'd make my own timber windows and get some glass in from Germany and make them. But then, of course, you start working in a job and you're busy and you suddenly find that it's small business. It's not a nine-to-five job. So there's kind of more work there than days, really. And that's how the whole kind of let's just buy them from Germany. yeah, that's what kind of kicked that off.

Jess Kismet (04:21)
Yep, takes up a lot of time.

locally

Michael (04:29)
So yeah, and the windows that we were looking at, one of the important things for us was right away, not just to get any kind of plastic window or really good high performance window, but also kind of from a sustainability aspect. I really like timber windows. There's all sorts of timber around in the world, of course. There's tropical.

harvesting of timbers. There's timber that come from Siberia that kind of are very kind of common on the German market as well. And for me, it was important to not just have that kind of performance aspect, but also sustainability aspect. And one of the things that kind of really brought us toward our current supplier is that their kind of ethical and sustainable kind of background, they committed to a German scheme that says all the timber that they use for their own manufacturing has to come from within 300 kilometers of the factory.

So it's sustainable German forestry versus questionable kind of, you know, we all know about the stories about, you know, tropical rainforests being cut down for all sorts of things. And, yep, there's certificates, but there's been also issues with all the certification schemes. And I know from having grown up in Germany, obviously, the way that Germans do forestry, rather than those big plantations that Australians might be used to, actually harvest from actively used forests or recreational forests. They pick out individual trees.

And it's still a recreational forest and it's actually beautiful forest to go into, to, yeah, exactly. They, they, they, get the really high quality trees from certain areas rather than kind of clearfading whole area and getting all sorts of stuff that they completely use. It's, it's, it's different. Yeah. Yeah. The forest leaves while it's being used for commercial purposes. And it's pretty cool. I really liked that about it. So.

Jess Kismet (05:42)
really? So they kind of take a little bit from here and a little bit from there. my goodness.

destroying the soil in the process when you constantly turn it over. Yeah, wow. It's a living for...

That is really cool. think timber and forestry,

it's definitely an area that I have not learned much about in my travels. And it's something that when I was learning about the leaky building crisis in New Zealand and they were talking about how they didn't treat their, they stopped treating their timber frame, like their timbers and then the quality of the timber and all this blah, blah, blah. I was like, my goodness, timber and where it comes from and how it's treated and the quality of it is absolutely crucial.

Michael (06:25)
Peace.

There's so many follow-on effects. mean, people always think about carbon miles and imported carbon and things like that. And then again, plastic to timber is kind of an easy kind of step. And you think timber is more sustainable because you have this in the body carbon. Plastic windows are made from non-reviewable resources. There's raw oil that needs to be extracted off the ground and processed, make it plastic in the first place, things like that. But then timber is like, where does come from? How far has the timber actually traveled before it even is being made into a window? And that kind of chain that

Jess Kismet (06:34)
Mm.

Mmm.

Michael (06:59)
even comes before the windows are made in the first place. And is that part has that been done sustainably or not? And it's really important as well. So it's a ⁓ long complicated kind of journey until we get to our products. That's right.

Jess Kismet (07:04)
Absolutely. But we don't think about it. It's convoluted. Yeah,

yeah, yeah. Very cool, very cool. So when you talk to builders who are new to Passive House, I mean, I've written in the question Passive House principles, but I know we're not allowed to say that anymore. But let's talk about it. Yeah.

Michael (07:22)
Yeah, look, that's great. think that's really, I know, think that's great. That's a great part of the question. Passive false principles. Yeah, exactly. So

that's one of my kind of big things. I find the passive false principle term a bit of a misconception and a problem because it kind of, to some degree, pushes people away from certain principles if they don't actually end for passive false. And I think there's no such thing as passive false principles. They're general common, good building practice principles, essentially.

Jess Kismet (07:35)
Mm-hmm.

Mm-hmm.

Michael (07:50)
And all those things are as important in any building. it a passive house or not a passive house? So passive house, can think of like a Ferrari in terms of a car, super high performance. But how many people do you see on the street that actually drive a Ferrari? So they're great. But all those principles also apply to buildings that don't go quite to the same performance level. And the balance is a really important issue there. So maybe if you just go through the principles again, so passive house principles are generally understood as air tightness.

Jess Kismet (08:09)
Mm-hmm.

Michael (08:17)
they've got super insulations or very very kind of thick insulation in your walls, seamless insulation or thermal bridge reduction, high performance windows and then the ventilation system with heat recovery. And I think one important thing that's actually missing there and that's kind of a bit of a double up with the insulation, I think the insulation should be kind of one point, should always be seamless as possible and the level again that I talked about then is more the how much, how close you get to pass-by's performance or how much insulation is in there but

And the thing that's missing in the whole thing is actually the solar heat gain control in terms of how much energy comes in through your windows. So high performance windows make sense, but especially Australians are often used to from traditional construction to have your part of your solar heat gain control is having internal blinds and fittings and curtains and things like that and fixed external kind of passive shading elements. But if you start looking at higher performance double or triple glazing,

Jess Kismet (08:49)
Mm hmm.

Michael (09:07)
those internal things don't do anything for you anymore from a thermal point of view because your glass is such a better insulator compared to what you put on the inside. Anything that comes with your glass you have to deal with inside the building. Passive shading elements are okay in some circumstances, but they're usually designed for the 21st of December solstice, know, highest kind of sun angle and for the 31st of June when the sun is at the lowest, but then we have shoulder seasons.

Jess Kismet (09:17)
Mm-hmm.

Yeah.

Michael (09:34)
And shoulder seasons means now we're looking at, know, March, April, where those passive shading elements don't work for you anymore. And the sun comes right in because of a much lower sun angle. But we have 30 degree days now in April still. So literally that ⁓ our seasons kind of change. have longer summers, hotter summers, and then sun comes in. And in my mind, the thing that works best is external active shading. So we have blinds, we can press a button when you want them.

Jess Kismet (09:42)
and it's still hot as in Adelaide in March. Yeah.

Michael (09:58)
and can put them away, especially if it's a gray day, if it's cold outside or something, you want to get as much light in as possible, where passive shading elements might actually obstruct your views. They might shade you when you don't need the shade. So it's kind of a lower kind of light quality inside your building. Use blinds that you can control ideally. That's what was the other thing. So, yeah, the second part is the not...

taking into account some of those principles if you're not aiming for passive house. And we get that argument a lot. He'll say, well, know, airtightness is really important from an energy efficiency point of view, but we really don't kind of want to get to passive house performance because it's so expensive or whatever. So we don't need to be quite as airtight and we can then ignore, for example, internal wraps. And then kind of turn around and say, well, actually, internal wraps are not the airtightness. That's kind of one misconception. The second thing is that

Jess Kismet (10:46)
We did talk about this in New

Zealand, we talked about this in Auckland, I think. There was a discussion around is it an air barrier or is it a vapour control layer? And that internal layer is a vapour control layer.

Michael (10:52)
Yeah, correct, correct.

Correct.

It is a vapor control layer and the vapor control layer works ideally optimally if it's also airtight. But it also works if it's not airtight, because airtightness is actually addressed much, much more easily from the external side of the building. So your weather-resistant barrier on the outside, your weather membranes, your external sacking or whatever term is used, it's much, much easier to get really, really airtight. And then if you, for example, use a... If you're worried about leakage through air from the inside of the building towards the outside,

Jess Kismet (11:05)
if it's also airtight.

Michael (11:28)
If you're taking like box or something and I find it really hard, I'm very visual person and I've got a box here, you poke a hole in it. So it's leaky from the inside, but it's very, very airtight. tape all the corners and everything from the outside and you try to blow into it. Nothing goes in because it can't go anywhere because it's sealed up on the outside. Right? So if you're worried about leakage of air from the inside of your structure, from the inside of the building towards the outside, but the outside is airtight.

Jess Kismet (11:38)
Mm-hmm.

Michael (11:54)
it can't even enter your structural space from the inside because they're from the outside, if that makes sense.

Jess Kismet (11:58)
thought you

guys he was super smart. He's pointing out stuff that I hadn't even thought of. Of course.

Michael (12:01)
So then it's not quite as

important anymore to get the insight really, really airtight as well, but it's really still important from a vapor control point of view. And that's where kind of there's later questions that you're asking about it, of course, we can maybe get to that later in terms of what people are struggling with the detail and stuff like that.

Jess Kismet (12:16)
Yeah, because that was going to be my question. I was

going to say, well, could we just actually talk about this for a little bit? Because people ask me about air tightness, of course, all the time. And they say, well, can I use the external membrane as my air barrier? And I said, well, yeah, the membrane is air tight. But the primary air barrier is ideally on the inside of the frame. Now, what you're saying is that it could be either side.

Michael (12:23)
Sure.

It be either side. It's great if it's eight head on the outside, but it's really, really important and much easier to do if you do it on the outside. Did I say inside first? Sorry. It can be on the inside. It's good. But it's much easier to do on the outside. So maybe I say, look, because it's so much easier from the outside, focus on that first. know, external part, you have a box of a building and you don't have light walls. You don't have funny kind of corners. You don't have bulkheads. You don't have complicated kind of junctions that are usually on the inside.

Jess Kismet (12:55)
Yeah. Yeah.

And you're saying it's easier. Why is it? Why is it?

Okay. Okay.

Michael (13:15)
Sealing

the inside airtight with wall frames that are kind of going through the airtight layer. You have the hangers that attach to the ceiling. Trying to seal around all those little penetrations, it's really, really difficult and much easier than on the outside, I think.

Jess Kismet (13:27)
So if you've got a house that's completely wrapped in an airtight, where there is a stiff barrier, like roof walls down to the slab, everything's wrapped, what happens to vapour dry from the inside in a cold climate? It's warm and humid. Where does it go?

Michael (13:44)
So cold climate, that's very good. So we should probably put that caveat in as well. kind of talking mostly relief and climate zone five up to eight in terms of the topics we discuss here. So, you know, ⁓ basically it's in south of the Queensland border, everything south of that essentially anywhere where you can get frost and areas that can be cold for a while. And yes, there's a vapor drive from the inside to the outside. And that's kind of one of my kind of passion.

Jess Kismet (13:53)
Yeah, which is called.

Mm-hmm. Yeah.

Michael (14:08)
little projects as well, trying to educate people about like, does it actually, how does it actually work? Why do we have a vapor drive from warm to cold or from the inside to the outside? So warm air can hold a lot more, lot more moisture than cold air. And we know, for example, that even if it's so, so, similar example, imagine you have zero degrees outside and it's, it's fog, you know, 100 % relative humidity, lots of condensation essentially. Fog means there's like little water droplets in the air.

Jess Kismet (14:12)
Yep. Yep.

Michael (14:36)
which means you already have had condensation, which means the air can't take any more moisture. That's why you see mist or fog. As wet as it can get on the outside. Then inside, maybe you have 40, 50 % relative humidity. So it kind of, in our mindset, it feels like inside is dry, outside is wet because you have mist. Inside there's no mist, okay? Makes kind of sense. So there should be more moisture on the outside than on the inside. That's not true though, because warm air can hold so much more moisture.

Jess Kismet (14:56)
Mm-hmm.

Mm-hmm.

Michael (15:02)
You still

have roughly twice as much moisture on the inside from grams per cubic meter point of view compared to the outside. And that's really what counts in terms of where the moisture tries to equalize between inside and outside. And I can go on forever talk about vapor pressure, stuff like that, but it's essentially a pressure difference between inside and outside from the moisture point of view. And it goes through kind of your building fabric. goes through the materials that are vapor permeable, even if they're airtight. And that's of course the external wrap. we're trying to get

Anything that comes through from inside, we try to not stop. So imagine you wear a plastic raincoat, you start sweating. If you have a cortex jacket, you're meant to not sweat. that's kind of the idea. But if you're looking at it a point of your insulation layer, the insulation already kind of gets warm from the inside to cold to the outside. So somewhere in there, if moisture goes through your insulation and then hits that external wrap where it's meant to go through as vapor.

Jess Kismet (15:38)
Mm-hmm.

Michael (15:51)
It will already get so cold that you even get some condensation inside your insulation layer. ⁓ And then we look at plastic raincoats or vortex jackets when you actually go for a jog. So going jogging in a vortex jacket, you still start sweating. So that's kind of a similar effect to getting condensation in your wall when you're living in a building because you produce a moisture inside, even with a vapor permeable wrap on the outside. And that's not the key word. The wrap is vapor permeable, but it's also waterproof.

Jess Kismet (15:56)
Mm-hmm.

You're frozen. Can you hear me?

Ahem.

Michael (16:18)
⁓

Jess Kismet (16:19)
So you're saying equalized pressure from inside to outside. You know, we understand that high humidity wants to go to low humidity, high heat wants to go to low heat. ⁓ And what I'm asking is when you've got an external air barrier and you've got high vapor pressure or high humidity inside and it's pushing to the outside, you want that to be able to release through the vapor permeable membrane.

Michael (16:27)
Correct.

Jess Kismet (16:40)
But if you don't have an air, an internal air barrier, how much of that pressure, cause you know, you blew into that box and if it's airtight, it's going to go in because it's already full and you can't get any more in. So how does that work?

Michael (16:50)
Okay, so that's another topic. So there's

two types of ways of how moisture can get through your structure from the inside to the outside. So the blowing through the box into the hole is more like an active vapor transport through air leakage. If you have, of course, air leakage in your building, warm air from the inside leaks through your structure. It transports the moisture that already is in the air towards the outside. It kind of hits cold surfaces and make a condensation.

Jess Kismet (17:04)
Mm-hmm.

Michael (17:15)
But the second way of vapor transport through your wall is through your structure itself, through vapor permeable materials. So we know that the external wrap is vapor permeable, so it is meant to have the moisture pass through so it doesn't get blocked. You know, the comparison to a plastic raincoat where it starts building up because it can't get through, so you have it vapor permeable. And problem though is what I said also with the active vapor transport, because inside your wall insulation is warm on the inside, actually cold on the outside, you're already starting inside your wall to hit areas and surfaces where it gets colder.

And both modes of transport, the active one with the air moving through or the passive one with diffusion through your structure, that moisture starts hitting those colder surfaces. You actually get condensation inside your wall. So imagine maybe if you use again, Gore-Tex jackets, think they're great example. Gore-Tex jackets are meant to keep you from sweating when you wear one because it breathes. But then you go for a run and the Gore-Tex jacket still starts sweating. And that's kind of what we're looking at in buildings, you know, with a bep-a-pem-a-rap, it's like Gore-Tex. But actually if you live in a building, it's like you're going jogging.

Jess Kismet (17:55)
Mm-hmm.

Yes.

Michael (18:14)
You're producing moisture, you're cooking, you're showering, you're sweating as well. So you're constantly producing moisture. It's more like you're running. An empty building is like you sitting with a Gore-Tex jacket. A lift-in building is like you're going up for a little jog and you still sweat. The problem with Gore-Tex is Gore-Tex is watertight. It's vapor open, but watertight so that the wet moisture inside your wall, how does it get through your Gore-Tex? How does it get through? And I think I really loved that when you had that interview with Joe a few months ago from Canada.

Jess Kismet (18:16)
Yeah.

Michael (18:43)
this kind of idea of improving energy efficiency first and you're actually changing the physics, how your walls work, how moisture gets transferred through your wall. Because the way that traditionally vapor gets, water gets through your external wrap is it gets vaporized again. So for vaporizing that moisture inside your wall, you need energy. Where does it come from? It comes from the inside, from the warmer environment. But now you're having lots of insulation in there as well. So the energy doesn't actually come through anymore to vaporize your water. So your water sits in your wall, it can't get out.

Jess Kismet (18:48)
Mm-hmm.

Michael (19:11)
It can still get vaporized and also from the outside if you have them, know, north facing walls or roofs that get hit with sun again during the day when things start warming up and then they can pass through. problem is really though with shaded walls or with really super cool walls and super cool roofs where you have so much moisture getting in that kind of warming up here it is not quite enough to actually dry things out again. And that's where that internal vapor control layer is so important to stop it from getting into your wall in the first place.

Jess Kismet (19:39)
Mm-hmm.

Michael (19:39)
And the

problem with our kind of general construction plasterboard and the inside vapor permeable wrap on the outside, the plasterboard is as vapor permeable as your class four vapor permeable wrap. Almost one to one, like almost exactly the same, but vapor permeability. So as easily as vapor can get through your wrap on the outside, as easily can it get into the wall in the first place from the inside.

Jess Kismet (20:00)
Does it depend on the paint?

Michael (20:03)
It does depend on the paint, but normal paints like, you know, your living room or something, you're not putting this kind of watertight acrylic kind of glossy stuff on walls. Generally, it looks pretty ugly. Like it's as vapor open as your paper will wrap. And then the problem is, of course, it can get in very easily, but then it turns into water, into liquid water from vapor because it condenses because it hits cold surfaces and then it can't get out anymore. So what you should try is to actually have a higher resistance on the inside. And in Germany, there's kind of a rule of thumb.

Jess Kismet (20:13)
Okay. Okay.

Michael (20:30)
you're trying to build at least 10 times more vapor inside on the inside compared to the outside. So 10 times more tight. So 10 times less readable, less, that's in a, again, south from Queens, Queens, all the way down to Tassie and further cold climate, so it's right here.

Jess Kismet (20:35)
10 times more vapor, 10 times more vapor tight on the inside. And that's in a cold climate, right?

Down. Yeah.

And in a hot climate, it's 10 times more vapor tight on the outside. Because, yeah, just want to make sure because there's people from all over who listen to this. Yeah.

Michael (20:50)
Well, you have to reverse it, obviously. Yeah. So it depends. It depends again. It depends on where you are in that kind of climate range. yeah,

let's assume just, you know, 80 % of Australians live kind of in that area. you're 20%. You can... That's right. But it's, yeah, that's right. But interesting. and I didn't even realize, but, know, northern Queensland, a bit further inland, people get frost there. So Armidale and around that area and north from there, you're supposed to Queensland.

Jess Kismet (21:03)
Yeah, you're in Canberra, I'm in Adelaide, we live in cold climates, what we talk about every day. ⁓

Yeah, inland, yeah.

Michael (21:19)
It gets really cold still and there's periods where it's colder for longer, not exactly close to the coast. So it is relevant for all those areas as well. That's why I say 80-85 % of Australians live in those kind climates.

Jess Kismet (21:20)
Inline for sure.

Mm-hmm.

Yeah,

yeah, yeah. So what you're saying is airtight external barrier, vapour can still get to it, even with your like analogy of blowing into the box. It moves through a different means, not through active transfer. Yeah, like a diffusion.

Michael (21:43)
it moves through your wall structure itself, through your plasterboard. You think you're making airtight plasterboards, it's fine.

But it still goes through that actually as well. And it goes through it quite easily. think more easily than people realize because you think, know, class four vapor permeable wrap on the outside is to allow things to dry out. Well, things can get into your structure already as easily as they can get out. And then it's actually harder for them to get out even with that class four wrap because you don't have vapor anymore because you have actually liquid water in your wall. So you have to vaporize it first again to be able to pass through.

Jess Kismet (21:58)
Mm.

Mm-hmm.

Mm-hmm. Mm-hmm.

Michael (22:13)
That's the hard thing. Then ideally you should have no insulation in your wall to make that work. low energy building, badly insulated, healthy building, great works. So we need to start putting insulation in and the more insulation you add, the higher the risk gets for more condensation in your wall. And then you have to do something on the inside. that's, I think sometimes where I think that's where kind of our kind of policy makers and the whole kind of really the vibe of the community has failed to some degree where we kind of driving for this.

Jess Kismet (22:21)
Beautiful.

Mm-hmm. Mm-hmm. Mm-hmm.

Michael (22:40)
energy efficiency without understanding. Old houses had already mold problems. know, the really leaky buildings with no insulation. Some mold problems, but generally kind of okay because they're so leaky things dry out again. So mold doesn't grow continuously. There's short periods where you have a bit of wetness and then it dries out again. That's fine. The more insulation then you add, and because we haven't actually fixed that small mold problem to start with in your crappy, in our old, sorry, I call them crappy buildings because I feel they are.

Jess Kismet (22:51)
Mm-hmm.

You

Michael (23:06)
I don't want to be rude to anyone, but we haven't even

fixed kind of the healthy building issue there, and now we're kind of making it worse by not understanding the physics and adding more insulation.

Jess Kismet (23:17)
Yep, yep, totally. And that's where some

of the policies in government where they've insulated buildings in Melbourne has gone very badly wrong. They insulate them without understanding the knock-on effects. I mean, I just know of that one particular one, but yeah. So passive house principles, let's not, you know, you can't...

Michael (23:26)
Yeah. anyway, yeah, the camera as well. ⁓ Yeah.

Sorry, there's one other

example that I'd really like to mention. And that's again about the whole balance thing. So, the cause people focus on energy efficiency. And that's essentially a bit of a kind of a, you know, you have a spreadsheet with kind of certain heat losses, heat gains, all that kind of thing. And you try to kind of adjust kind of certain performance, certain area to get a certain outcome. Essentially, it's one number that you end up with that you have to be to be energy efficient, which is your energy consumption.

Jess Kismet (23:40)
Yep.

Michael (24:05)
the heat or the amount of energy required to keep you building at a certain kind of comfort level. You can achieve that in many different means. So you can have a super insulated kind of half a meter thick wall, lots of insulation, but you have single glazed windows. You can then still hit your overall target by having a certain energy loss by just improving certain areas. And one of the things that gets really kind of ignored and forgotten is the thermal bridging kind of problem or thermal break.

Jess Kismet (24:30)
you

Michael (24:31)
I think that's one of the hardest ones that's the industry struggling with. That's the least understood. There's a lot of kind of technical structural engineering that's involved in there that kind of people, that scares people off, I think. And there's a really famous example that I love that's from the US. When they had similar problem, know, design and chambers architects design a building, it's called the Aqua Tower in Chicago. If you look that one up, Aqua Tower, amazing design. So the reason why it's called Aqua Tower, because it has got all those wraparound balconies that wave in a certain way.

within the glass facade and it looks like bit like water waves. And the plan was there, you know, lead, they've got this lead certification system in the States over there with platinum gold, gold certified, platinum certified, and it was meant to be the highest performing building from an energy efficiency point of view. So they had all those measures in there, structural thermal racks were in there from the start. And then it went to the builder. And then what happens, it's a great thing, it's called value engineering.

where they look at all those components and there's a certain budget and we're stretching it a bit. let's see where we can save money. We have still this goal. We need to get a energy efficiency target. Have to be below that number that the building can consume in terms of energy. How do we get there? And then you can imagine almost like a music mixing board with sliders. You increase that and reduce the other one to get to your certain outcome. And so they looked at everything, looked at all the costs and thought,

Jess Kismet (25:41)
Yeah.

Michael (25:47)
structural thermal breaks never happened before. There's a kind of a new thing coming over from Europe. It's tricky maybe, not quite sure about the structure there and things like that. How about we kind of let them away, leave them away and compensate by putting more insulation in and maybe slightly better windows. So that's what they did, went along and left structural thermal breaks out, put more insulation in. The sums in the end looked great. So the number at the end, energy efficiency, fantastic, lead, platinum certified. Great. But then saw the building is in Chicago.

And people might know Chicago is also known as the Windy City. It gets really, really cold. So they get their minus 10s, 15s, 20s or something because it's close to the Canadian border up there. Cold winds coming from right through from the polar area and really cold, strong winds. And you can imagine the building with lots of wrap around balconies. It's a bit like a motorcycle cylinder with all those little fins, a great heat exchanger. So all that wind coming past there.

Jess Kismet (26:21)
really cold.

Michael (26:42)
balconies that stick through the structure, no thermal breaks, so concrete is already a good conductor. Then you've got all that steel in your concrete that conducts even better. And they had those freezing cold balconies that kind of conducted right through into the building. And then of course, very energy efficient. But people lived in there and they started producing moisture and massive condensation issues. So the whole thing turned to class action in the end. Some people, AquaTower, call it the largest indoor waterfall in the world because it's literally concrete slabs that are dripping.

Jess Kismet (26:53)
Yep.

Mm-hmm.

Wow.

Michael (27:11)
moisture inside, raining, stalactites, I don't know, because it's so wet and they didn't take into account those little things. And that's what I say, like this is kind of one of the effects that it has when you just focus on energy efficiency and don't understand how a building actually works as a whole in terms of the building physics. And that's what I'm really passionate about. that's what I'm talking about. And that's, think, a fantastic example. And the architect afterwards has vowed to never, never

Jess Kismet (27:30)
100 %

Michael (27:37)
take shorter cuts again, always look at the big picture thing, but you know, the building is not there. It's cost a few billion dollars to build it. You can't just knock it down and that's this kind of, I don't know, in Germany probably would be condemned for being too unhealthy to live in because of all the conversation issues. I'm not sure actually what they did. No, I think they went afterwards, tried to wrap all the balconies insulation externally, which is of course a huge effort as retrofit and way more complicated than installing the structural film and brakes to start with.

Jess Kismet (28:07)
So you're saying that every single balcony was a gigantic thermal bridge just sucking cold into the buildings and that's what caused the issue? Wow.

Michael (28:11)
Yeah, yeah, correct. Going straight through. That's you look

around Australia, how multi-resi construction looks like these days with that really fast precast construction, concrete walls going straight through balconies, going straight through. Same thing every time I see that, kind of my heart hurts a bit. She like, sorry. So don't take it's really sorry. Long story short.

Jess Kismet (28:18)
Yeah.

Totally.

Listener heed Michael's warning. Wow.

Michael (28:36)
I think it's really important to look at a building as a whole and you have to balance all those different approaches. There some things people would never think like, know, foundations, know, they're structural big things and cost lots of money digging all those piers down to the ground. Let's just skimp on a few and leave a few out. know, you kind of and what we're trying to get the people to understand is to know that that's the basics. The things that we actually talk about are the basics of building. Every building should have that.

It's not passive host principles. It's basic building principles and they have to kind of be looked at a balanced way. Another great example that I love is like the image of putting glasses on the naked person, where people go for one really high performance product and maybe something that looks really good like windows, you know, that's a good example, but forget about the rest. And that's actually one of kind of my formative experiences that I had in Australia as well, where when I was, I think it was before I started working for Laros actually, we had bought our house and we were looking at

improving things and you know, there's a thing called the sustainable whole staying camera. So you go around all those other people's houses that have done great things and they're very proud about their improvements. And I went into this place and they were showing all the things off and then new double glazing that they put in very proud and spend lots of money on it. And it was a fairly windy day and I thought like something's going on. The curtains are kind of, you know, waving from left to right on the inside and thought, well, maybe, maybe they had a window open and they looked closer and it's like, I kind of can see.

light through there between the window and the wall, what's going on. And there's a gap between the window and the wall, like you could see straight through. And that kind of understanding of like using one really good product, but not even understanding how to integrate properly into your structure, how to make it work with the rest that's around it, and that balanced approach that's important, and that's got nothing to do with passive force. really, know, air tightness to whatever level is important, but then you also need to look at insulation, insulation ideally.

Jess Kismet (30:05)
Mm-hmm. Mm-hmm.

Yep, 100%.

Michael (30:28)
as seamless as possible, so reducing thermal bridges for any type of building. In a balanced approach, no point of putting triple glazing in, no insulation in your wall, no point of having a half a meter thick wall full of insulation and think of those windows, no point of having no air tightness and all those other two things, know. Same with thermal bridges, if you don't address them, then you're kind of focusing all the problems that you would have with otherwise in your structure to that one point that you haven't addressed yet. That's kind of that example with the aqua tower, I think.

Jess Kismet (30:46)
Mm-hmm.

Yeah, and I will.

Michael (30:58)
where they have a really

energy-efficient building, still very energy-efficient, but fails completely on so many other levels. it's, yeah.

Jess Kismet (31:03)
A complete failure. Not

habitable almost. will look up, well not almost, not really habitable. I will look it up. I will look it up and I love a good building failure case study and I'll link it in the show notes for anyone who wants to read a little bit more about that.

Michael (31:10)
Yeah, look it up. It's a very nice building too. looks really cool. Yeah, architecturally fantastic.

You

Jess Kismet (31:22)
so Michael, a lot of builders are getting increasingly nervous about condensation and moisture issues. So what is the most common failure that you see that leads to this most common issue that you see that leads to this failure? And how can it be avoided with smarter detailing or better sequencing?

Michael (31:40)
Yeah, guess first we have to kind of think about what does actually moisture failure mean or what's the failure? Does it mean your building is falling apart or collapsing or something? In my mind, moisture failure is when you have mold in your building. Who wants to live in a mold building? It's really unhealthy living environment. We know that mold can cause a lot of problems, asthma, other things. Makes you kind of physically, I think...

of weak concentration issues, all the kind of stuff. There's lots of effect in our body, think. So having mold in your building, think that's in my mind, that's when you failed. especially, and that's where the sequencing thing comes in as well. I find quite a few buildings that I go into and they're already moldy right from the very, very start. And I think the biggest problem there and the failure there is that the traditional kind of way of how Australian buildings are built is you put the frames up.

and then they sit in the weather for a while, then eventually you get some windows and they come in and they get installed and the frames are still sitting there in the weather. And then after some months, maybe some kind of wraps go on, maybe, or anti-converse or something, and then things get wrapped up. So having those timber frames sitting in the weather, exposed for months and months, especially bottom plates, so that's kind of the bottom element of timber that sits in the slab, for example, they get completely saturated. They're wet, they're sitting in water.

And then because the builders are also on a schedule, they have to finish things off and then there's not necessarily time to let things dry out and things could wrap, things get insulated, internal wall gets put on and you're ending up with a structure that's already wet and moldy right from the very start in the brand new building. So that's my, in my mind, the kind of way where people have to rethink the sequencing. In my mind, you put the frames up, you put the wrap up right away. You protect your frames.

Jess Kismet (33:16)
Straight away, yep.

Michael (33:17)
keep them

dry, you have a nice, much more comfortable working environment, you can do then other work inside with being out of the weather, out of the wind, and you're protecting your structure right from the start. So as fast as you can, put your frames up and protect them.

Jess Kismet (33:25)
Mm-hmm.

them straight away. actually had a friend go to New Zealand ⁓

over the July school holidays and she sent me some photos of, I'd heard of people using tents to build their structures in, in like Europe and in New Zealand, but I'd never actually seen it or, you know, knew anybody who had actually seen it and she did. So over in New Zealand right now there's construction projects going on where maybe they're not using a building wrap, maybe it's an alternative wall system and they're actually building it inside a tent because it's winter and it's cold and wet.

Michael (33:40)
Yep.

Inside the fence, yeah.

Yeah, I think that's

maybe a bit of an extreme. I think that's obviously works, gets you out of the weather. I think it's also okay to actually build your structure as a tent essentially right away. Even if it does get, you know, one or two days of rain is no problem. If you wrap it right away, then things can dry out again over the many, many, many months until the building is actually finished. The problem is where it's already sitting many months in the weather without being protected. So even if you don't have a tent right from the start, if you put the wrap on, then you have a tent that you can work in, but it's your building.

Jess Kismet (34:07)
Yeah. Yeah, it's not realistic to have tense. Yeah.

Yes.

Michael (34:25)
don't have to double up on the tent I guess. I think people probably still use the membranes in museum as well after they've done their tent but they don't even want to get anything wet to start with.

Jess Kismet (34:32)
Yes, Yeah, it's, it's,

it's not realistic to ⁓ put up a tent in most, most construction sites in Australia. So, you know, the sequencing of the wrap and the frames in the wrap is extremely important. I put up a post recently about a structure here in Adelaide that was left out in the winter, I reckon at least two winters, maybe more. The first builder was, ⁓ I think they went in solvent and another builder took over.

Michael (34:54)
⁓ okay. Yeah.

Jess Kismet (34:58)
And that building

is completely destroyed. Like the frames are black. They are black. And I drove past a few months after I first noticed this building and it was being finished, bricked up, clad, ready for people to move in. They were bought off the plan years before. was 2021. They were bought off the plan by unsuspecting homeowners. The renders looked lovely. And the actual as-built product has not been protected from the weather.

Michael (35:04)
Warp twisted bow.

Mm-hmm. Mm-hmm. Yeah.

Jess Kismet (35:27)
And it's just a health hazard, like you wouldn't believe. And the comments on the post were, that's happening around the corner from me, or I know another project this is happening to, or yeah, my neighbors, or yeah, this, yeah, that. There's so many examples of timber structures that have been left out in the weather, not protected, and have gone moldy before they're even finished.

Michael (35:46)
Well, think that's

just the common way of how buildings are built. think pretty much almost every building that doesn't have the right wooden right away is one of those. think that's probably 98 % of all new buildings really.

Jess Kismet (35:56)
Mm.

Michael (36:01)
And another thing that I find, again, is really important in terms of moisture failure. Of course, we had COVID, we had lots of issues with supply and people went a lot over to steel frames.

Jess Kismet (36:08)
yep.

Michael (36:10)
So one of the other things that mistake that I think people make, even if you do everything perfectly right from a vapor permeable wrap on the outside insulation, good insulation in your steel frames, and then even the internal vapor control layer, it still doesn't work. So steel is such a good conductor, you're putting the plasterboard on the inside onto your steel, and you actually can after sometimes even less than a year, you can start seeing the outline of your steel on the inside of the plasterboard because there's more growth. The steel gets so cold in winter that it conducts right through.

having a vapor time to wrap on a, sorry, the vapor control layer on the inside on a cold surface does not work. So the condensation happens right on that surface then. So it doesn't, so what you want to do with the vapor control layer is you want to stop moisture from getting to any cold area inside your structure. But because the cold area is right on the inside, it's right there, right? So it doesn't stop moisture from getting to the cold spot. And then when people think, exactly.

Jess Kismet (37:02)
And the vapour control layers are also water sensitive too, so

if there's condensation they'll just break down.

Michael (37:05)
So

getting them wet, they start breaking down, that's right. And then the next thing is like, people understand, okay, steel frames, have to put a thermal break in. But they put, actually, they don't put the thermal break in, they put a thermal break on. So you see things then where they have this thermal kind of break strip that gets attached to the outside of the steel frame or to the very inside of the steel frame, and they're totally useless. A thermal break only works if it's inside the insulation layer. So you have to surround the thermal break with insulation to make it actually work.

Jess Kismet (37:10)
Yeah.

Michael (37:36)
Putting a strip on the outside means that the edges of where it overlaps with your external... The outside of your structure is at outside temperature. Imagine zero degrees outside means the outside of the structure is at zero degrees, which means the inside and the outside of your thermal break are both at zero degrees. Totally useless. It's not thermally breaking, not thermally disconnecting anything. And the same if you do it on the inside. The wall on the inside is 20 degrees, the room is 20 degrees, the inside and the outside of your thermal break, if you...

Jess Kismet (37:54)
Mm-hmm.

Mm-hmm.

Michael (38:04)
just stick it on on the inside, they're both the same. So doesn't work.

Jess Kismet (38:07)
So you're saying that steel

has to be completely encapsulated?

Michael (38:11)
The more the better. So you have to bring at least your insulation into the thickness of the thermal break or ideally further, which doesn't work with a 10 mil kind of strip. That product doesn't really exist that then kind of makes that product. From an insulation point of view, you have your insulation that's more thick. There's other risks if you start then sticking like, for example, a 10 mil or 20 mil XPS on the outside to kind of...

cover up that thermal break. That's where we come into the two-thirds, one-thirds rule kind of thing. That's another topic. maybe, so look, maybe let's stick there for now. So thermal breaks don't work if you just stick them on here. They have to be inside your insulation layer. And that's another big mistake that we see that people do all the time. It's a thing where you spend more money.

Jess Kismet (38:39)
That's another issue.

So hang on, hang on, sorry.

The thermal break has to be inside the insulation layer or the thermal bridge has to be inside.

Michael (39:00)
Thermal break. So steel is a thermal bridge that's already into insulation layer, but the thermal break then really has to be as much in the middle of the insulation layer as possible. It doesn't work if you just stick it on. Thermal break. Wrecked? No, that's the big problem now with steel frames, right? So maybe think about that when you do steel frames. So you can, there are ways. You have to either double up, so two steel frames with the gap, and insulate them between as well so they don't go right all the way through.

Jess Kismet (39:03)
Yes. Yeah.

A thermal break. but you can't put a thermal break in the middle of a piece of steel. You can't split it.

Michael (39:27)
That's of course then kind of, you know, people put steel in because it's cheaper than timber. So that's kind of counteracting that, you know, doing something cheaper, I use steel and I don't have the termite problem and all kind of stuff. Not realizing that they're kind of building themselves a mould bunker. Especially commercial construction, heaps, everything is done in steel. So many schools that are built in Canberra at the moment that are all steel. Steel that runs straight through from the inside of the outside structural elements, like big steel beams that have, you know,

Jess Kismet (39:43)
a petri dish because you still got plasterboard. You still got, yeah.

Michael (39:54)
support candy livered roof overhangs stuff like that. Yeah, they'll be sweating on the inside.

Jess Kismet (39:55)
yeah.

I've had

a number of calls from modular builders who are so confused as to why their roof spaces are all mouldy and Yeah. Yeah. Very highly conductive. Yep. Yep.

Michael (40:06)
Yeah, yeah, yeah, because there's structured elements, very highly conductive elements that run straight through from the inside to the outside. So a thermal break has

to be always as much as possible in the middle of the insulation layer. Otherwise it's useless. Not useless, but less effective. It's definitely useless if you only stick it on to the surface. A thermal break on the surface is not a thermal break, which is kind of what's done at the moment in the industry. So that's another big thing.

Jess Kismet (40:26)
Which is all we do. Okay. Alright. Alright. Okay.

Interesting. Thank you. I learned something.

Michael (40:35)
one of my

passion kind of trying to explain it to people.

Jess Kismet (40:40)
I'm learning a lot here. budget. All of this stuff is great. Thermal breaks, you know, good windows, who has wide blouse. Let's talk about balancing all of that with budget.

Michael (40:43)
Martin, everyone's got one.

So yeah, there's a cost of course to everything, right? People have a little budget and people want to have nice things. Generally the things that people focus on are the things that they can see. So that's high-end kind of fittings, finishes, nice kitchens, good appliances. One of the problems with the things that we do is that they're all invisible. They're inside your building structure. And that's why they're of often easily ignored, especially then if people don't understand why they're actually important.

Funny thing is nobody kind of questions foundations of a building. I guess they kind of make more sense. If you don't have good foundations, your building might fall over. That's actually true. But I think all the things that we talk about are just as important as good foundations because who wants to live in a moldy building? ⁓ maybe shift if budget is an issue, think about if maybe some of those kind of concepts that people have as their dream house can be shifted from

Jess Kismet (41:38)
you

Michael (41:47)
things that can be changed later in your building to things that cannot be changed easily later in your building. So focus more on that stuff that are hidden inside your structure. Get that right first. Then you can down the track, maybe save a bit more money and get those really high-end, the best kind of $500 taps in your bathroom, better kind of ovens and appliances, marble bench tops in your kitchen. Another thing is size. Maybe think about, like, do you really need a 350 square meter house for two people?

If you have budget constraints, the easiest thing is to make it bit smaller. Maybe, you know, that third grumpers room. Squabbit has cost building size costs. If you can't afford it, or if you can only afford the giant big building by building it where you have mold in your structure, maybe think about that.

Jess Kismet (42:20)
Yeah.

Yeah, yeah, we went to, I was at the Passive House Conference a couple of months ago and there was a presentation there who was talking about public housing in, goodness, where was it? Somewhere in the Eastern Seaboard. ⁓

Michael (42:48)
Maybe

in Canberra because I have that here, public housing, steel frames, all that kind of stuff. Very sad story, find. Okay. I'll pass it house public housing. Great. Okay.

Jess Kismet (42:53)
No, no, no, this was Passive House public housing. Literally. Yeah. Yes.

And they were small. They were government funded public housing units, but they were certified Passive House. Completely, you know, within a reasonable budget that could be, you know, most people would be able to come at, but they were smaller. And I just from the outside, they look like your average brick veneer.

public housing project, but on the inside they were healthy air, mold free, comfortable, know, peace of mind for the people who were inside those buildings, who were the more vulnerable people in the community. And I just thought, fabulous. Like it doesn't have to be.

Michael (43:41)
I think maybe that's

another big misconception. People think passive houses are really expensive and they are, mostly because passive houses added on as an afterthought. So you have your existing design and then you try to make it passive house versus trying to sign with that kind of mindset right from the very start. And the other thing is people think passive houses are always small, kind of boring boxes.

Jess Kismet (43:52)
Mm.

Mm-hmm.

Michael (44:02)
So both are not true. So you can A, make a passive host cost-effectively by thinking it right from the start. And it doesn't have to be a boring box. Yes, if it's not a boring box, it's generally more difficult to make a passive host. And it doesn't always easily get there. And then you might have to spend lot more money. But especially if you think of it right from the start, think where your airtightness layer has to be, think where thermal bridging might be and design it right from the start and an afterthought.

save a lot of money and you can actually offset some reasonably high costs by having a much more efficient building that has lower energy needs. You can replace your slab in slab hydronic heating that's know 30-50 grand of whatever with massive energy. By offsetting it maybe spend more money on the windows for example to get get higher performance there and you don't need that system in the first place. know can actually replace some systems that cost a lot of money as well.

by going for passive policy offset some costs. So there's cost offsetting, there's good planning right from the start, and you can build almost this cost effectively, especially if you don't take it on afterwards as an afterthought.

Jess Kismet (44:55)
Mm-hmm. Mm-hmm.

Yeah, I couldn't agree more. Couldn't agree more. You gotta think about these things from the very start and then it's a whole lot easier.

Michael (45:10)
Yeah.

And it might influence your design. It will influence your design. That's true. But, and then it probably gets to something that is in your budget and still can look nice as well. So they're not mutually exclusive. You can almost make anything into a pass or false, but you know, there's, there's, then it costs more. If you have this crazy design with lots of walls, optimize your service area to some degree. Some degree as I say, because that then comes down to people's budgets. if they allow for that right away, yeah, it's not.

Jess Kismet (45:15)
Mm-hmm.

Yeah.

Yeah.

Michael (45:40)
What other people's reach, think.

Jess Kismet (45:43)
It's definitely not. I think ⁓ people, I think if the, if the homeowner comes to this design process with an open mind and is willing to compromise on the things that they had their heart set on in order to achieve a passive house, certified passive house outcome, then there can be a lot more, the process is a lot easier. I think the problem comes, and I know just around my office, a lot of the, there's a real contention between what people want.

and what they can afford. And when it comes to Passive House, I think that the grand ideas of their beautiful dream home have to be potentially, not always, but potentially pared back a little bit in order to allow for all of those performance elements that are going to make the house much more durable and much more healthy. So I think that the open-mindedness has to be there from the outset.

Michael (46:28)
Because people.

Yeah.

And I think if people also think about, they would never question the foundations of the building, know, whatever their grant design is, and they know that's the cost and that's part of the budget. And as I said before, those kinds of things are as important as a foundation of your building because otherwise you have all those other problems. And also maybe not every building actually has to be passive house performance. It can be a high-performance building that's not quite there. Not everyone's driving a Ferrari, Camry is a really good car that gets you from ATB as well. It has tires on that has a windscreen on, you know, I kind of

Jess Kismet (46:36)
No.

Mm, yep.

Mm-hmm.

Mm. Mm. Mm-hmm.

Michael (47:01)
I love those little comparisons. Everyone knows cars, you know, and people think like, oh, you know, they told me I shouldn't have tires on because we've never done that before. We've been driving in our rims. And essentially you can drive a car like that. It's a bit uncomfortable. It's not very healthy. You have to brake very carefully because it doesn't stop suddenly. But it's possible. Windscreen, same thing. You put your airplane goggles on, you know, you don't have a windscreen. You all the flies. You get a bit wet when it rains. Uncomfortable. But it kind of works. But then you have this really shiny car. Essentially everyone's driving their Cabriolet.

Jess Kismet (47:04)
Mm.

Hahaha

Boooo

Michael (47:31)
No roof, no windscreen and no tires on the rims. That's kind of the focus on. But you know, the foundations that say there's even rims there in the first place, you're not driving when you break kind of discs or something. That's like the foundation of the building. Nobody questions them. You have to have them. You can't not have them. But the other thing is like, oh, windscreens, you know, this piece of glass that's kind of curved in two dimensions is probably very expensive. And we always had our goggles. It worked as well. Don't worry about that. You know, it's kind of that idea. So it's...

Jess Kismet (47:42)
Yeah.

So unnecessary.

All right, mechanical ventilation. Can we let's talk about the difference between HIV and ERV and what ERV actually does because I think the understanding of HIV, at least in the people I talk to is fairly well understood. The concept of it, but ERV less so. So could you please explain for the listener and for me?

Michael (48:15)
Yeah, so basically

what does mean HIV heat recovery ventilation versus the energy recovery ventilation. And ERV does also moisture recovery essentially. you have any recovery ventilation system, heat or energy has two air streams. One in going, one outgoing, they go through heat exchanger and the heat exchanger works on like the outgoing air. Like the winter case, the outgoing air heats up the incoming air and they're very efficient. And then there's two types of heat exchangers.

One is just a metal one that's a very good conductor and has a very good heat exchange. That's your HIV. And one actually has a kind of almost like a functional membrane. And that also has good heat recovery, but also lets moisture pass through between the air streams. And one of the things that people are not aware of if they're actually building high-performance building with a ventilation system, any ventilation system. And in winter you bring cold air in from the outside. You're totally drying out your building. 24-7 you're bringing cold air in and that gets warmed up. Then it's, as I said before, as much drier.

And then the inside air and you're actually drying out your house, you will suddenly start to have to humidify your building to not get your kind of ice shriveling away because you really dry out. And the funny thing is in a bad building, it's important to do that because you want to avoid condensation on all those cold surfaces. But you still even get condensation from know, firmly non-broken windows, even with the EFV running full blast and like 20 % relative humidity inside where it's really unhealthy. So your eyes shrivel.

but you still have wetness. And that kind of understanding of having a dry building that's healthy, but also having a healthy living environment by not having your ice shriveled because it's like Sahara conditions, that's kind of the difference. And so the ERV helps you to actually retain some of the moisture that's inside so you don't totally dry out your house. Or going to the tropics or climate space where really humid outside, it actually rejects some of that moist air that comes in back outside again, so you don't need to run a dehumidifier as much as otherwise.

Jess Kismet (49:40)
Yeah.

Michael (50:05)
So that's a big advantage. And then look on paper, usually from a, you know, you could call it temperature recovery point of view, not as efficient because, so what happens in an HIV, you get condensation and the incoming a stream is really, really cold. You have the outcome in the a stream passing on the teat to the incoming a stream cooling down. And then you have condensation air with moisture cooling down.

condensation needs to be drained away somewhere, so you have your ventilation system somewhere in the middle of your house, you need to allow for condensate drain. And then ERV you can usually ignore those condensate drains because there's enough moisture being passed on into that warming up airstream that you don't get as much condensation, almost nothing, inside your unit and you actually don't dry out your place. So that's kind of the big difference.

Jess Kismet (50:52)
So

ERV is applicable in cold climates still, like drier climates.

Michael (50:55)
cold climates and really hot climates,

but you'd be surprised. I would say the EIV is almost always a better choice than an HIV in terms of drying things out. Or like, you go to humid climates, then so partially kind of dry climates in winter, but also sometimes really humid climates in summer, you want to keep that moisture outside. And then having a ventilation system running in summer, it's really hot outside, cool in outgoing air cools down the incoming air.

Jess Kismet (51:03)
Interesting.

Mm-hmm.

Michael (51:18)
but you still have all the moisture coming in and then you run into even more moisture problems because cold air can hold less moisture. You bring warm moist air in, you want to reject as much of that moisture right from the very start as possible. So really humid climates, really cold climates, if you look at Australia, it's almost everywhere until you get to a place where it's almost in between, which doesn't happen either. cold or humid sometimes at the same time in many areas. So I think generally they're the better choice.

Jess Kismet (51:29)
Mm-hmm.

Mm-hmm. Mm-hmm.

Michael (51:45)
They are especially for counterflow systems. So there's another kind of differentiation. There's counterflow heat exchangers, there's rotary wheel heat exchangers, there's all sorts of other different technologies. If you have counterflow heat exchangers, they're probably the most efficient units and they're also a lot more expensive as an HIV. So there's HIV cores, again, core, heat exchange core with like aluminium heat exchangers or something. They're a lot cheaper than those kind of vapor permeable kind of, you know, almost kind of membrane heat exchangers.

Jess Kismet (52:14)
Mm-hmm. Mm-hmm. Okay.

Michael (52:15)
But I think still worthwhile. I think they're

better choice in the long term. Yes, there's a high upfront cost for many EREs.

Jess Kismet (52:23)
So why

are HRVs more widely used than are ERVs?

Michael (52:27)
because they look better on paper. They look like they're more efficient because they don't take into account that you then have to run a humidifier or dehumidifier in the background somewhere that also uses energy. So HIVs are generally having a higher temperature kind of heat recovery essentially. air coming in, air coming out, 20 degrees inside, zero degrees outside. In an HIV, the air comes in at...

18.5 degrees and then Eav only comes in at 17.5 degrees or something. So they look better on paper from a heat recovery point of view, but people don't realize that they also have to...

Jess Kismet (53:01)
So you're saying that with an HIV,

you're saying with an HIV you might have to run a dehumidifier.

Michael (53:06)
Dehumidifier and humidifier in have to more anyway. And you have to run a humidifier in cold climates.

Jess Kismet (53:08)
⁓ in human climate. Yeah. But I know that it's a recommendation.

Because in my building biology study, we are told never ever, ever use a humidifier ever. There's no reason ever to use it. Because that creates a moisture, creates a high humidity mold problem.

Michael (53:23)
Well, ⁓

Yeah, okay, then the people, don't understand how dry actually things get when your eyes start dribbling and how unhealthy you get when your nose starts drying out, your mucus kind of layers start drying out. You actually get more susceptible to diseases, to colds and COVID, any of those kind of things.

Jess Kismet (53:36)
I lost you again. Hello?

you

Michael (53:47)
So people get sick much more easily in really, really dry buildings because their defenses don't work as well. That's a lot that exactly that's massively increased exacerbated the effect if you use HIV only.

Jess Kismet (53:51)
And that's using an HRV only. Potentially there's a risk there using HRV only.

And even if you're producing moisture in the building with breathing, cooking, bathing, washing, even in those circumstances.

Michael (54:08)
So it depends. It might be good enough, but because things get extracted right away, usually from the points where the moisture is produced on your bathroom, have your UV running and extracts all the moist areas and where you need that moisture, for example, in your bedroom or something, it might not get there. yeah, I would be interested. Again, we've got a passive house, certified office here and now we've got the timber cracking in the walls and cracks opening up.

Jess Kismet (54:14)
Mm.

Interesting. Okay.

Michael (54:34)
And now we have a relative humidity of well below 30%. We have two humidifiers running 24-7 to try to keep the moisture levels up. We turn the ventilation system off overnight because there's nobody here, of course, to not bring more cold and dry air in because we're really drying all that space. But also it's an office. So we're not cooking or showering here, but we have like six, seven people sweating, breathing, drinking, drinking coffees, making tea, things like that. The kettle is running. It's not enough. It's not anywhere near enough.

Jess Kismet (54:40)
Wow, okay.

wow.

Breathing. Yep.

Michael (55:01)
We have that's even with one ERV. We've got one ERV and one HIV running in parallel and upstairs downstairs. Upstairs we've got the ERV and it's not enough to even then maintain healthy humidity levels. yeah.

Jess Kismet (55:12)
That's really interesting and I think the key message there

is to monitor.

Michael (55:16)
Exactly, monitor, see what's going on and then react. And so I grew up in Germany and I know from even just having radiative heaters, everyone had their little kind of water kind of pockets hanging on the heaters that were evaporating. You had to refill every two or three days to keep humidity levels up to a certain degree. That's no ventilation at all. That's just open doors and windows every now and then to let fresh air in and then bring in dry, cold air in, heating it up and you're drying out the inside essentially. And things got to dry and that's in houses that are hooked in lift and shower and still getting too dry.

Jess Kismet (55:18)
Mmm. And react to it.

Mm-hmm.

Michael (55:46)
All the buildings that I lived in as a kid had humidifiers, essentially, as part of the package. You're heating a house, you have to humidify it because things just get too dry. Just even from opening doors and windows a few times.