Stop with the foil faced blanket
“Money turns to water.”
Anyone who has tried to move from being on the tools to quoting their own projects knows the feeling. A decent job lands, the money hits, and for a second you think you’re flying. Then the supplier invoices roll in, insurance lands, fuel, tools, tax, and suddenly you’re staring at your account wondering how you’re working this hard and still not sure if you’re making money.
From carpentry to Pro Clima (via physics)
We sat down with Dave from Pro Clima in Sydney at the Built To Last studio, and the conversation went straight into the stuff builders actually deal with. Dave’s title at Pro Clima is Technical Innovation Engineer, but what that really means is he’s one of the people you call when a detail is about to go sideways.
What makes his perspective land is his background. He started as a carpenter straight out of school, did his apprenticeship and Cert IV, spent about ten years in the industry, and even did a stint in Canada before coming back and subbying. Then he did something most tradies never consider. He went back to uni and did a Bachelor of Science in Applied Physics, and somehow that brought him right back into building, just from a different angle.
He admitted that as recently as a year earlier he wrapped a mate’s house in foil thinking he was doing him a favour. We have all had that moment. The moment you realise you were doing what you thought was right because no one ever taught you better.
Builder business is not taught (and it should be)
That “money turns to water” line came from the messy transition between hourly work and quoting jobs. Dave wasn’t reckless; it’s just that no one teaches you how to manage cash flow when you’re suddenly responsible for materials, subcontractors, tax, and timing.
We went on a tangent here, but it’s the kind of tangent that saves businesses. GST is not your money. Tax is not your money. Super is not your money. If you don’t separate it, you’re basically gambling. We talked about systems like Profit First and splitting accounts so you always know what money is actually available to run projects. It’s not glamorous, but it stops the slow panic that creeps in when you’re always behind.
The details that keep failing (and why)
Dave’s day-to-day now is helping builders and designers work through envelope details, condensation risk, and weatherproofing logic. When we asked him what details he hates seeing, he didn’t hesitate. Box gutters. Flat roofs. Balconies over living areas. Planter boxes. Different details, same theme. Water.
His point was blunt. If you are detailing something that is obviously going to leak over a living space, you are not designing. You are just choosing where the failure will happen. The box gutter chat got even sharper when he said if your house can have a critical failure because a tennis ball blocks an overflow, you have bigger design issues.
Compliant is not the same as good
We also got into the code and why “compliant” is not the same as “good”. Dave explained DTS in the simplest way we’ve heard. Deemed to satisfy is the shittest you can build a house without going to jail. It’s a pathway, not a benchmark.
Pro Clima sits more in the verification and testing world, but even then, you can still get pushback from certifiers who only want to see what they recognise in a standard detail. That’s why CodeMark matters. It removes the argument.
Carpentry is a launchpad
We finished on something we care about a lot. Apprentices and career paths. Dave’s story is a reminder that carpentry is not a ceiling; it’s a launchpad. He said carpentry gives you a grounded, intuitive understanding of physics because you’re building it every day. You get instant feedback. You learn what works. You learn what fails.
And the best part is he reckons the next generation is hungry for it. When he talks to young chippies, their eyes light up. They want to build better. They want to understand. That’s the shift the industry actually needs. More people who can explain the hard stuff in plain language, and then help fix it on site.
LINKS:
Pro Clima - https://mindful-builder.captivate.fm/proclima
MEGT - https://mindful-builder.captivate.fm/megt
CR Kennedy - https://www.crkennedy.com.au/
Connect with us on Instagram: @themindfulbuilderpod
Website: www.yoursanctum.com.au/
Connect with Matt:
Instagram: @carlandconstructions
Website: www.carlandconstructions.com/
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[00:00:00] Matt: Hamish and I, we're in Sydney at the moment. Um, we're actually again from the real Proclima Built To Last studio. We're at headquarters. Um, Hamish and I got to share a single bed last night. It was cute.
[00:00:12] Hamish: We did not. Did you really? We definitely did not.
[00:00:14] Matt: I was a little swoof.
[00:00:15] Hamish: It was, it was very- Tons of stuff in the building industry
[00:00:18] it's very explicit when we were actually booking that we were having separate rooms. Very- Separate rooms,
[00:00:24] David: same bed ...
[00:00:24] Hamish: very, very explicit.
[00:00:26] David: Yeah.
[00:00:26] Hamish: Very, very explicit. But no, I went to the gym this morning with, um, our boss, Dan. Oh. It was good to get up.
[00:00:31] David: He's still walking.
[00:00:33] Hamish: He's,
[00:00:33] David: yeah, well,
[00:00:34] Hamish: I mean, he's, it was a light session given it was with Dan, so I feel pretty good.
[00:00:39] Matt: I slept in. Yeah, me too. Um, actually, funnily enough, I was walking past, went on a nice walk through Coogee and, uh, came across a few passive houses there. Saw a lot of... Actually, yeah, there was one, it was in Coogee. It was, I think the f- ironically, the builder was called The Mindful Builder.
[00:00:59] Hamish: Yep. [00:01:00] Or is it- Or is it Mindful Building?
[00:01:01] Matt: Mindful Building, yeah.
[00:01:02] Hamish: Mindful Building. Is
[00:01:02] David: there any legal dispute
[00:01:05] Hamish: there? I think- No, I actually think that when we were looking at names that we noticed that he actually had this name. It was
[00:01:10] Matt: a bit laughable, isn't it?
[00:01:10] Hamish: Uh, and we're like, "Oh, okay. Well, maybe we should do The Mindful Builder Podcast."
[00:01:14] Matt: I think that's what we thought.
[00:01:14] Yeah, it didn't work. Yeah. Yeah. So anyway, you might be wondering who today's guest is. So Dave is from Proclima. What's your email job description?
[00:01:24] David: Email job description is technical, uh, innovation engineer. Yeah. I should know that better.
[00:01:30] Matt: So what is really cool is, uh, Dave, you're originally a carpenter.
[00:01:34] David: Mm-hmm.
[00:01:35] Matt: And you've sort of transitioned into a, what I reckon is a really cool job, but you, you're probably a little bit more... Well, Dan's obviously got a carpentry background, but you've gone through from understanding university degree to building science and stuff. But-
[00:01:49] Hamish: Hey, why don't, why don't we let Dave-
[00:01:51] Matt: Yeah, but where I'm gonna go is like- Yeah
[00:01:52] let's go back to the start. Just tell us who
[00:01:56] David: you are. Yeah. Um, like you said, I did [00:02:00] carpentry straight out of high school, just the classic apprenticeship into cert four, and
[00:02:07] Hamish: just- Always, always Sydney-based?
[00:02:08] David: Yeah. Yeah. So, well, Sydney-based, and then I went to, when I finished my apprenticeship, moved to Canada for a couple years.
[00:02:14] Oh, where
[00:02:14] Hamish: were you in Canada?
[00:02:15] David: Vancouver mainly.
[00:02:16] Hamish: When?
[00:02:17] David: Uh, for f- Longer ago than I like. Uh, 2014
[00:02:22] Hamish: Oh, well, mate, I was there 2003, 2004, 2005.
[00:02:26] David: Yeah, right.
[00:02:26] Hamish: So, yeah.
[00:02:27] David: Building, or?
[00:02:28] Hamish: Uh, lot of snowboarding.
[00:02:29] David: Yeah, so- I
[00:02:30] Hamish: was in primary school Lot of, lot of snowboarding. Uh, lots of mountain bike riding. I went there for a season, stayed for three years.
[00:02:36] David: Yeah. Incredible. It happens, right?
[00:02:37] Hamish: Yeah, yeah. Yeah. Incredible.
[00:02:39] David: Yeah, so did a little bit of building there, not much. Yeah. Similar to you. Um, came back, just subbied for a while, and honestly, got kinda sick how money just turns to water when you're trying to subby. Like, you sort of wake up one day with a big fat bank account, then the bills come through from the supplier, [00:03:00] from your insurance, you know, and it's just like, yeah, it got hard to sort of keep on top of.
[00:03:06] So I got pretty fed up, and then, yeah, just decided to go to uni, do a physics degree, and I found this job, and sort of the perfect match. Wow.
[00:03:18] Hamish: When did you do your physics degree? So-
[00:03:20] David: 2020 to '23 Sort of end of 2023 So
[00:03:25] Matt: was it a broad physics degree?
[00:03:27] David: Applied physics.
[00:03:28] Matt: So
[00:03:28] David: what's that? Bachelor of Science in Applied Physics.
[00:03:30] Matt: So you're going through really anything. You could have done any avenue .
[00:03:34] David: Yeah, I had dreams of building rockets actually, but the more you try to get away from the building industry, the more it drags you back in, so here we are.
[00:03:43] Hamish: Yeah, I mean, it, it, it makes sense though that you're now here.
[00:03:47] David: Mm. Yeah, I did laugh when I saw- You're really relevant
[00:03:49] the job description. I was like, "Wow, that is the weirdest perfect combination." Yeah. Yeah. Yeah,
[00:03:53] Hamish: did you ever think that your, that your carpentry and your n- new education would, [00:04:00] would come together like that?
[00:04:00] David: Not this specifically .
[00:04:03] Hamish: Yeah. Yeah. How long have you been pro climber now?
[00:04:05] David: Uh, just a little over 12 months.
[00:04:06] Hamish: Yep.
[00:04:07] David: Yeah. Yeah.
[00:04:08] Hamish: Yeah, right, that's the perfect-
[00:04:09] Matt: It's like, yeah, it's y- I think this, and the whole, I can see where this episode's gonna kinda go, and it's gonna give people the confidence that, um, carpentry can be a starting point.
[00:04:19] Hamish: Totally.
[00:04:20] David: Um- It is the starting point, and I love it, as a starting point for almost any career, I think.
[00:04:25] Do
[00:04:25] Matt: you still call yourself a carpenter?
[00:04:27] David: Oh, I like to gas myself up and say builder 'cause I did my Cert IV, but
[00:04:31] Matt: yeah.
[00:04:32] David: Okay. Yeah, no, absolutely. That's just like
[00:04:33] Hamish: calling a passive house a passive house if it's not certified, though.
[00:04:36] David: Yeah . Yeah. True that. True that.
[00:04:38] Matt: Ding, ding, ding. Um, uh, you said money turns to water when you're a subby.
[00:04:44] David: Yeah.
[00:04:44] Matt: I really wanna go into that conversation. I've written
[00:04:46] Hamish: that down too.
[00:04:47] David: I really struggled with that, to be honest. It was one of the hardest points. There's, like, a big transition when you're a apprentice, then you become a carpenter, and maybe you do your Cert IV, and you're subbing, and it's like [00:05:00] where's that transition from doing your own work to subbing from someone else?
[00:05:05] And as you're transitioning, that's when it's really hard to sort of keep on top of your finances, and, you know, just even make heads or tails whether you're making money or losing money. It sort of gets a... It, it was a lot for me, to be honest.
[00:05:19] Matt: Is this hard? Um-
[00:05:20] Hamish: And were you, were you hourly rate subbing, or were you quoting projects?
[00:05:23] Or quoting-
[00:05:24] David: So it was that transition between hourly rate subbing to quoting my own projects- Yeah, okay ... that I struggled with. So, like, you'd get a big, you know, $30,000 deck, pergola sort of thing.
[00:05:33] Hamish: Yep.
[00:05:34] David: Which probably wouldn't even get you footings these days, but that is even- Or you fuel.
[00:05:38] Hamish: Yeah, or you fuel.
[00:05:39] Exactly.
[00:05:41] David: The realities of sort of- That paying the suppliers, paying, you know, for the concrete that comes in, all that, and all the bills that go out, and then you get lump sum and it's just managing. I wasn't good at it.
[00:05:55] Hamish: Yeah.
[00:05:55] Matt: You can see how quickly a tradie ends up with a brand new [00:06:00] Ram ute and a boat, a jet ski, and then go, "Ah, fuck, got no money."
[00:06:04] David: It looks so easy from the outside in, you know? Yeah. And, like, you don't... Especially when you see young fellas in their P plates with this brand new Land Cruiser, like, leveraging all this money. You're like, "Oh, don't do it." Yeah.
[00:06:17] Hamish: I mean, forget about the boat, forget about the jet ski. Like, it's just the car.
[00:06:20] Like, you know, you're absolutely right, 19, 20-year-olds driving around in a $60,000 car.
[00:06:25] David: Yeah.
[00:06:25] Hamish: Like, how can you even possibly get ahead?
[00:06:28] David: Yeah.
[00:06:29] Hamish: Yeah, the... And we were talking about this this morning with Dan, and we were coming here. Like, there seems to be this really... Like, our, our tax system for so long has benefited buying these types of cars.
[00:06:40] David: Mm.
[00:06:41] Hamish: And w- if you go to Europe, go to UK, like, everyone's driving around in vans.
[00:06:46] David: Yeah, exactly.
[00:06:46] Hamish: Which I, I understand are as cool, but practically speaking, like, I had a van for a bit. Better. You don't have to tow a trailer around, you just open up the, open up the- It's more secure.
[00:06:58] David: Dan and I argue about this all the time, [00:07:00] the van versus ute discussion.
[00:07:02] Hamish: But like, how is it holding- Do, do you know what? This, Dan dr- Dan drives around in a freaking Mustang. Yeah. Like, he really can't, like, throw rocks in glass houses. But
[00:07:07] Matt: the Ram, like, what is the point? That's not
[00:07:10] Hamish: a ute. Okay, so I, I tow a lot. So at one stage- Mm. Sure ... I had a 79 Series, so, you know, I justified in my mind that I towed two or three times a week.
[00:07:19] You know, I've since got rid of that and now I'm in a BYD Shark, and I don't, I don't tow much anymore. Yeah. Yeah,
[00:07:24] Matt: right.
[00:07:24] Hamish: And-
[00:07:25] Matt: Have you felt you don't need to as well? Like, you've realized, "Oh, don't need it."
[00:07:27] Hamish: Well, I think the, the idea was that because I had the car, it was up to me to tow. And now it's like we- we've got a, um, like, Isuzu truck.
[00:07:35] Mm. Which, all right, we'll just get Jamie to pick it up.
[00:07:38] David: Yeah,
[00:07:39] Hamish: yeah, yeah. Totally. You know, that makes more sense. So, uh, look, I don't know. This is me, uh, after 20-odd years in the industry saying this. Mm. And it's easy for me to kind of look back and go, "Well, I should've done that 10 years ago."
[00:07:49] David: Yeah.
[00:07:50] Hamish: But I know 10 years ago I wanted to have the Amarok or whatever, so.
[00:07:54] Put
[00:07:54] Matt: your hand in front of the camera.
[00:07:55] Hamish: So yeah, I get, I get it. I understand.
[00:07:57] David: Yeah. It's, it's, it's a learning experience [00:08:00] that like, you know, when you're young and you start getting that first paycheck, you're like... And then the, the car salesman gets in your ear. He's like, "Oh yeah, you can afford these repayments."
[00:08:08] And- What
[00:08:08] Matt: do car salesmen know? How do they know your bank account? Few th- few things on this.
[00:08:13] Hamish: Oh, no, no, hang on. I just want to l- everyone's got this misconception that it's a tax deduction.
[00:08:18] Matt: No, it's your money.
[00:08:19] David: Mm.
[00:08:19] Hamish: Like, you still... Yeah, it is a tax deduction. 100% it is, but you still need to pay for it.
[00:08:24] David: Yeah.
[00:08:24] Hamish: The money still needs to be in your bank account to pay for it. It's only when you kinda get over a certain threshold-
[00:08:30] David: 100% ...
[00:08:30] Hamish: that that actually makes sense. Yeah. You know, and again, I'm realizing this now, 'cause you know, I've got some high purchase, um, stuff through the business, and like right now my motivation is to pay them off.
[00:08:40] David: Mm.
[00:08:41] Hamish: And then not have them
[00:08:43] David: Yeah.
[00:08:43] Hamish: Anyway, you, you live, you're living the-
[00:08:44] Matt: Can we, can we just, it's very important part. Everyone wants to reduce tax. Oh, and they gloat, "I didn't pay any tax." I tell you what, if you didn't pay tax, it means you made no money.
[00:08:53] David: Yeah. Yeah.
[00:08:54] Matt: Like, it's very, like, the higher you... If you say, "Oh, I had to pay 100 grand in tax last year," it means you [00:09:00] did pretty well.
[00:09:00] Mm. Good for you. You should be wanting to have 100, 200, $300,000 in end of year tax payments because it means you're profitable.
[00:09:08] Hamish: Yep. Yeah.
[00:09:08] Matt: Um, good, when you say that money goes to water, um, anyone out there that has this problem, um, Profit First is a great book-
[00:09:17] Hamish: Yep ...
[00:09:17] Matt: on this. Uh- Okay ... what it does, and it's also, it's called Profit First Attorneys.
[00:09:22] It sets your bank account into, like, five or six different bank accounts. So when, for, I have this, so money comes into one account, it's my income account. Mm. Then I have a materials and subcontractors, I have an OPEX account, I have a owner contributions, a GST, a tax.
[00:09:37] Hamish: Staff liabilities
[00:09:40] Matt: Yes, wages. Yeah, I have, I call wages.
[00:09:42] Yep. Yep. So yeah, so yeah, that's... I was just thinking in my head what I have in my account. But yeah. Yeah. So what happens, you work out the percentage of what is required based on your, your average P&L, and you go, "Well, last year I spent roughly 51% on materials," for example. Mm. That goes into that account. I spent 20% on wages.
[00:09:59] [00:10:00] That goes in that account. 10%- It's
[00:10:01] David: basically automating everything as much as
[00:10:02] Matt: you can. Yeah, you can, I mean, most banks you can't automate the payment- So, yeah ... but you've got to do it manually. But the good thing about manual, actually thinking about these things. So, um-
[00:10:09] Hamish: We do it, we do it very similarly, just to kind of close this out, and 'cause I think this is good information.
[00:10:13] So we've got an operating account. Yeah. So all my money goes into there. As soon as that hits, as soon as a, um, uh, an invoice comes in, I divide that full amount by 11. Now, I know that that's 10%, so I'm taking the full 10% of GST out and putting it in a GST account. Now, for people who know business, you never pay the full 10%.
[00:10:31] Mm. You know, it's usually somewhere between 3 to 5 or 6% that you're actually paying. Yeah. By the time you offset it with subbies and stuff coming in, that's what it lands on. But I know at any time I've got more money in that account that I know needs to be
[00:10:42] Matt: there. It's like a fire account too.
[00:10:44] Hamish: But then once I've taken that 10% off, I then divide the next number by 17%, which I know is what my overheads are.
[00:10:51] Mm. And I put that overhead, and I've, I've got an overheads account which pays me, which pays my VAs, which pays cars, which pays my, um, contract, [00:11:00] um, my pre-construction manager I then make sure that every single payroll, the I- IOS comes out. So super, your PAYG for your t- your team, and it goes into a different account.
[00:11:11] David: Mm.
[00:11:12] Hamish: So I've always got money in these other accounts to pay those baseline, um, requirements for the business, and then I know that the number that's in that pr- um, project operating account is to operate projects. All the other stuff has been taken out and it's taken care of.
[00:11:27] Matt: So super is actually becoming, I know this is going off track, you have to pay it each time you pay wages coming up.
[00:11:32] Hamish: Yeah, yeah.
[00:11:33] Matt: So the next-
[00:11:33] Hamish: Which is actually not a bad thing, to be
[00:11:35] Matt: honest with you ... No, it's actually small little payments, so it's not like you can pay it in the quarter or in the year. Yeah,
[00:11:39] David: see, I didn't even realize that wasn't- Ab-
[00:11:40] Hamish: And look, what- ... the
[00:11:41] David: standard, right?
[00:11:42] Matt: Yeah ...
[00:11:42] Hamish: while we're talking about, you know, little business tips, um, I pay my BAS quarterly- Yeah
[00:11:47] because I know that I've always got money in there And your AIS
[00:11:49] Matt: monthly, is
[00:11:50] Hamish: it? Yeah, but you can actually pay your BAS monthly. Yeah. So if you're not as good as paying- Yeah ... your BAS and you're kind of always sort of scraping the bottom of the barrel to pay it, you can actually [00:12:00] do it monthly. Yeah. Which makes it a little bit easier for your cash flow.
[00:12:02] And
[00:12:02] Matt: people might be like, "Oh, it's my money. Why would I pay the ATO?" Fuck yeah.
[00:12:07] Hamish: You know what? You can't, you know what? You're earning money ... It's not your m- it's not your money. You, you're n- You're not gonna make any interest off it ... And you
[00:12:09] Matt: ne-
[00:12:10] Hamish: and this is why I s- personally split it up, and I'm digressing totally here but- No, this is important
[00:12:14] I think it's a good,
[00:12:14] David: good conversation ... like, because it's the, you know, it's that transition between being on the books making X amount and then, like, you know, going out on your own, and everyone wants to do it but no one knows how to- Yeah ...
[00:12:26] Matt: take these steps- Do not talk this
[00:12:27] David: stuff ... and break this down- You're not, you're not talking
[00:12:28] like this. Yeah. You
[00:12:29] Hamish: know what? We've got, uh, some power saws in the background. Let's just deal with it. We're, we're- Yeah ... recording on location. But I think, you know, I look at that money that's in there as not my money. Mm. It's spent money. I l- But
[00:12:38] Matt: it's not your money ...
[00:12:39] Hamish: I look at the money that's in that operating account, and that's the money that I can operate on.
[00:12:43] Matt: Mm. And we've seen- Uh, this isn't just a builder problem or tradie. Like, we know architects that have engineers that have had this problem that haven't paid their BAS and tax, and that's the first thing the government flags.
[00:12:56] David: Yeah.
[00:12:57] Matt: Um, and they're now no longer here. There's a reason, so it is [00:13:00] a massive thing that you need to consider.
[00:13:01] It
[00:13:01] Hamish: serves you well when the government can see that you are paying your BAS on time and your IAS on time- Yeah ... all the time. Mm.
[00:13:07] Matt: Like, that's just- Probably get away with a little, few more things if you're paying everything to the- Yeah ... if they're seeing money coming through each month-
[00:13:12] Hamish: Yeah ...
[00:13:12] Matt: they ain't gonna be on after you.
[00:13:14] Hamish: Anyway, that- Yeah ... that's, uh, that's more for builder business 101 for- Yeah ... for today.
[00:13:18] Matt: So, um, but that doesn't take away from carpentry becoming the, the focal point of what you did.
[00:13:25] David: Yeah.
[00:13:25] Matt: And I think a really good point is that f- want, say 20 years ago, if you're a carpenter, the only option was then become a builder.
[00:13:33] Maybe a building surveyor. That, that, that was- That
[00:13:35] David: was the only op- not the only option, but it was the most profitable option, I, I think. Like, y- I saw a lot of my, the builders I worked for as an apprentice be able to flip houses and make a good living out of it, and like, it's, it's, it was set up a little bit differently for tradies to succeed to a certain extent, I feel like.
[00:13:54] Whereas now it's a lot harder.
[00:13:56] Matt: Physics degree at uni.
[00:13:58] David: Mm-hmm.
[00:13:58] Matt: Three years? [00:14:00]
[00:14:00] David: Three years, yeah.
[00:14:00] Hamish: How long were you a chippy before that?
[00:14:02] David: Uh, including the apprenticeship, about 10 years.
[00:14:05] Hamish: Yeah, okay. Yeah.
[00:14:06] David: Yeah,
[00:14:06] Hamish: so in, in the industry for a bit.
[00:14:08] David: Yeah.
[00:14:08] Matt: So then d- what did you do post physics degree? Was it straight into Proclima?
[00:14:12] David: Yeah, tried to get a job. It wasn't easy. Like I said, I had sort of, um- Uh, I was doing a internship at the uni in optics, and then was just looking for any sort of physics role, but everyone wants you to do a master's-
[00:14:27] Matt: Yeah ...
[00:14:28] David: PhD, and I'm just too old to keep going to uni and be a student, so.
[00:14:32] Hamish: What,
[00:14:32] David: what
[00:14:32] Hamish: were you doing for work while you were studying?
[00:14:35] David: Uh, my f- my friend owns a sheet metal fabrication business. Yeah. I would just give him a hand.
[00:14:40] Hamish: Yeah, okay. I s-
[00:14:40] David: Stuff like that, cash jobs for carpentry friends. Like, yeah. Yeah.
[00:14:44] Matt: Well, it's probably young kid, they're not sure what they wanna do, and they wanna go to uni and do something. Why not do a three, four-year carpentry apprenticeship, become a bit of a handyman, handywoman, and then go to uni, and you can earn some good money on the side?
[00:14:57] David: I think it's such a good idea. Like, like we were [00:15:00] talking about, went to Canada, but, like, you can live anywhere in the world and you have a valuable skill. Yeah. No. It gives you this absolute freedom to be able to, you know, move to any city in the country and earn a good living, you know? It's really empowering.
[00:15:13] And then develop your own assets as well when you eventually get to that point. It's... I love it. Yeah. It's such a good skill to have.
[00:15:20] Hamish: Yeah. And do you still, are you still pretty active now on, you know, trying to swing a hammer?
[00:15:24] David: Yeah. Trying to. Yeah. So, nah, I've recently picked up a place, so yeah, demoing that.
[00:15:32] Hamish: Oh, yeah,
[00:15:32] Matt: lovely.
[00:15:32] David: Yeah,
[00:15:32] Matt: firing it well. It's good. Um, so your job at Pro Clima.
[00:15:37] David: Yeah. What
[00:15:38] Matt: was... Did you know who Pro Clima
[00:15:41] David: were before this? Uh, no.
[00:15:43] Hamish: Did you know anything about Passive House or high performance
[00:15:45] David: home? No. So I often say Uh, you know, as recently as January before I started here, sorry to my mate, but I wrapped his house in foil thinking I was doing him a favor.
[00:15:59] [00:16:00] Um, and then, you know, like starting here, learning here is just like, like you do Passive House course, you get to sit next to Vili and Jesse and sort of just absorb, absorb, absorb all this information, and it's, yeah, been such a steep learning curve, but really, really informative and sort of you look back on a lot of the buildings you did and just like, "
[00:16:23] Matt: Oh."
[00:16:23] Yeah. We've all had that moment though.
[00:16:24] Hamish: Yeah. Yeah, absolutely. Totally. Um, I've got two thoughts running through my brain, so I'm gonna cross my... I saw Dan do this yesterday- Mm ... when we were at dinner table, so I'm gonna do this. I'm gonna come back to one of the- So just cross to have your reference ... I'll cross my fingers to, to, to remember.
[00:16:36] And he's like sitting there like talking with his hand crossed, and I'm like, "Why the fuck have you got your finger crossed?" He's like, "I was told to remember something." And then he forgot. Uh- Such a Dan. Um, it, uh, the point I was about to get to before Matt was, um, we live in a, this bubble. Yeah. And we're talking this is two years ago, not even two years ago, when you're like still wrapping- A year.
[00:16:58] Uh, yeah, a, a year ago. And still [00:17:00] wrapping a house in foil and thinking that was the good thing to do. Mm. Whereas we think about this now and think, "Fuck, you know, that's, you know, we're, we're in 2026 now, why the fuck are you still doing that?"
[00:17:09] Matt: Mm.
[00:17:10] Hamish: Uh, and it probably just goes to show how much the industry still, the broader industry- Yeah
[00:17:15] needs to catch up.
[00:17:16] Matt: And y- and within the year, you've been able to absorb that much information, bring your carpentry and physics degree to a point where you presented at the Building Physics Forum in Australia last week.
[00:17:27] David: Yeah, the other week. Yeah.
[00:17:28] Matt: Yeah, so like that is a huge amount of learning in a year to be able to get up and speak in front of some of the, probably the smartest people.
[00:17:35] Hamish: And how, how'd you find that, getting up in front of a bunch of people? 'Cause, you know, you're a chippy.
[00:17:38] David: Yeah. That's been another big learning curve. Um, a lot of what I did through last year was going to like events, training, presenting, just on sort of, you know, the realities of envelope design and condensation management, and really breaking that public speaking bone and, yeah, trying to sort of- work on that [00:18:00] because that was terrifying.
[00:18:01] Yeah, it is. That was, um, the Building Physics Conference, that was great, like really good opportunity to just talk to some of those people in the industry. Um, the actual presentation, like I, I'm happy with the content. I think my presentation has room for improvement. Do you know
[00:18:18] Hamish: what, though? Start somewhere.
[00:18:19] I've, I've actually found, and maybe I'm a little bit biased 'cause I'm sort of trade background, I am also university educated as well, but I've done spent most of my time in the trade.
[00:18:28] David: Yeah.
[00:18:29] Hamish: I usually find the most endearing and engaging presentations and conversations when someone's up on stage is generally someone who hasn't come from university, profession, public speaking.
[00:18:43] Like as a tradie, you know, we're not known to getting up and talking in front of people. Mm. And there's a r- there's a rawness and a realness and something that's, um, very familiar with someone coming up on stage and being- Yeah ... uncomfortable. Com-
[00:18:55] David: completely agree. In the Timber Construction Conference last year, there was [00:19:00] like a lot of high-end conversations, engineers, architects, then this truss manufacturer gets up and just is like talking very, uh, how would you say, frank about- Yeah
[00:19:10] the industry and everything, and it's just like so refreshing- It,
[00:19:12] Hamish: it's real ... to hear it. Yeah. Yeah, it's real. Like some of my favorite, um, presentations at Thrive, the, a Passive House conference, are generally when the builder gets up. Mm.
[00:19:20] David: Yeah. Definitely. '
[00:19:20] Hamish: Cause it, 'cause it's language... Well, maybe it's 'cause it's language that I'm more familiar with, but I think it's also just real-
[00:19:27] Matt: We
[00:19:27] Hamish: just tell
[00:19:27] Matt: it how it
[00:19:27] Hamish: is sometimes
[00:19:28] tell it how it is, yeah. Mm. Yeah. Yeah.
[00:19:29] Matt: You don't sugarcoat stuff.
[00:19:30] David: And don't try to overcomplicate things. That's, you know, engineers and scientists fall into the trap of assuming a certain baseline level of understanding or whatever- Yeah ... and talking above it, whereas I think a builder has a really good approach of just- Yeah
[00:19:46] you know.
[00:19:47] Hamish: I think the, the person who I admire the most when it comes to public speaking, who's freaking smart, is Cameron Munro. Oh. Like the way that- I haven't had the chance to hear him yet. I've heard him on
[00:19:55] David: podcasts- It's the
[00:19:57] Hamish: way- ... and
[00:19:58] David: stuff,
[00:19:58] Hamish: but ... the way that he can break [00:20:00] down really complicated, uh, topics into something that I can understand- Mm
[00:20:06] is, it's a real skill.
[00:20:07] David: Mm.
[00:20:08] Hamish: It's a real skill
[00:20:10] Matt: Um, what does day-to-day look like for you? What do you, what do you actually sort of... We, we talk about technical knowledge here. Yeah. Um, what, what are you... Are you helping solve detailing problems or?
[00:20:20] David: Yeah, absolutely. So like, uh, builders, if you call Pro Clima generally will talk to me or, or Villy.
[00:20:27] Um, but so generally answering technical questions, helping on sort of architectural plans and designs.
[00:20:35] Hamish: Designing out box gutters.
[00:20:37] Matt: Well, I was actually about to ask this. Good question. Box gutters. Well... What's your biggest hate of a detail that comes to you across your desk? Uh- That you're just like, "Why are we doing
[00:20:44] David: this?"
[00:20:44] Yeah. There's a few ones. Uh.
[00:20:46] Matt: List them. Let's go for it.
[00:20:48] David: I mean, box gutters is the low-hanging fruit. Unnecessarily flat roofs, balconies over living areas, planter boxes, or planter boxes.
[00:20:58] Matt: But they kind of are all... [00:21:00] And what's the common theme here?
[00:21:01] David: Water. Waterproofing. Yeah, yeah. Like, don't try to detail something that's obviously gonna leak over a living space.
[00:21:08] It's just never
[00:21:09] Matt: a good- It used to be in the code you couldn't put a balcony over a living space.
[00:21:12] Hamish: Did you really?
[00:21:12] Matt: Yeah, and I think they removed it. Huh. Don't quote me on that, but I'm 95%
[00:21:18] David: sure. I, I'll have to ask Villy, my encyclopedia on this. We,
[00:21:19] Hamish: we've brought up box gutters a few times, but you know, Matt and I have been here for a couple of days now, and we were actually out the back yesterday, you know, looking at a computer screen, you know, you and V- you and Villy were looking at, and I'm like...
[00:21:29] You're like, "Well, what, what should we do here?" And I'm like, "Get rid of the box gutter and put an eave gutter on it." Like-
[00:21:33] David: Good answer ...
[00:21:33] Hamish: it, and, and I joke, but if you think about it logically, I understand from an architectural point of view m- why you might want it. I, I get it, but- I don't. Yeah, I, I can understand aesthetically, I, I get it.
[00:21:44] David: Yeah, okay.
[00:21:45] Hamish: Yeah. But you could... But, but if that's what is gonna set your house apart, then you have failed as a designer.
[00:21:50] David: Yeah.
[00:21:51] Hamish: Or even- Put
[00:21:52] David: a fucking- Yeah ...
[00:21:52] Hamish: put an eave gutter on it and then put the design prowess somewhere else, 'cause you want to get that water as far away as bu- from a building as possible.
[00:21:59] David: And it's [00:22:00] not like only us as like builders and stuff, but like I have plumbing friends who are, there's very specific ways to design a box gutter to work, but even still it's risky. Yeah. And it's like why introduce that risk into your structure?
[00:22:12] Matt: But most people don't actually ca- calculate the flow rate of the box gutter.
[00:22:17] Right.
[00:22:17] David: Exactly.
[00:22:19] Matt: They just go, "Oh, two degree roof." They're like, "Yeah." "The minimum code is 300- 200 ... 300 high." Yeah. 175 m- mil high. And then-
[00:22:25] Hamish: Well, let's, let's just make it a little bit wider. But then do you know what it's not taking
[00:22:27] Matt: into consideration? That doesn't, that doesn't... That might not work ...
[00:22:29] Hamish: is, is the fact that the owner should get up there every six months and clean the gutters and box gutters- Totally
[00:22:34] and, and some power.
[00:22:35] Matt: Yeah, but that might, again- That doesn't happen ... that is a guess. That you've got to calculate the, the flow rate of that water coming off and how much square meterage on that roof is going in that overflow. Yeah. No,
[00:22:43] Hamish: I, I get all of that, but you know, in my mind- It's never done ... that should just be done.
[00:22:46] David: If you've got something in your house that can cause a critical failure from a tennis ball, I think you've got bigger design issues.
[00:22:55] Hamish: What do you
[00:22:55] Matt: mean
[00:22:55] Hamish: by
[00:22:55] Matt: that?
[00:22:56] David: If you throw a tennis ball on the roof, it clogs your overflow, and then it just leaks [00:23:00] into your house
[00:23:03] Matt: Yeah. Fucking, that's a very good- It's,
[00:23:05] Hamish: it's really is a really good
[00:23:06] Matt: point ... bec- because they all come down to water, and I think, um, the, the detail, like we, I think we need to firstly understand that Pro Clima isn't a waterproofing system.
[00:23:15] David: No. Very important to sort of, yeah, understand. It's like we encourage envelope design in its entirety, but like waterproofing and, you know, like wet area waterproofing, roof box gutter waterproofing, planter boxes, that's a whole separate like size and field of the code that people...
[00:23:35] Matt: What, what's the minimum fall? So minim- let, let's just work backwards here. Mm-hmm. Minimum roof pitch is actually one degrees, which is-
[00:23:42] David: Oh, really?
[00:23:42] Matt: Isn't that mind-boggling?
[00:23:44] David: Yeah.
[00:23:44] Matt: Who... And the f- the, the ironic thing is I constantly get plans that are like the spec'd anti-con on top of a one degree pitch. Like if the house moves, and where I build, where it's P-class most of the time, and in our soil reports we can sometimes expect, I've seen up to 62, [00:24:00] 66%, uh, uh, 62, 6 millimeters of movement expected in the soil.
[00:24:04] Are you, are you- That, that, that one degree might now, if that house moves, might be negative one degree.
[00:24:09] David: Oh, and if-
[00:24:10] Matt: And it goes the other way ... you're
[00:24:11] David: sagging anti-con over- Yeah ... the battens, if you're at one degree, what's that sag? It's negative three degrees.
[00:24:16] Matt: Yeah. And so what- Yeah. So I, and I understand when people wanna build on the height limitations and they've got their, their res code.
[00:24:25] Mm. I think res code needs to ease up to allow this an extra space for these structures to maybe to be on a pitch, but I think we should be looking at everything has to be minimum five degrees.
[00:24:37] David: I, yeah, I would like it, but, uh, the reality is pliable building membranes, they say you can go down to two degrees, which is not great.
[00:24:45] Like what's the difference between one and two degrees? Five degrees, yeah, like if you think about it over, I can't do the maths- 20 meters or something ... off the top of my head, but yeah. If you've got a five-degree roof, you've s- still [00:25:00] barely coming up on that encroaching sort of thing. So if you can design your roof to be, you know, 300 mil lower- And have that five degree fall, you instantly just put a better sort of long-term protection over your house
[00:25:12] Matt: But where I'm getting at is we don't design, or the people we usually see don't design at one degree.
[00:25:19] A box to gu- gutter is 10% of one degree.
[00:25:23] David: Mm.
[00:25:24] Matt: That's the fall that we have to achieve for a box gutter, so it's practically flat.
[00:25:28] David: Yeah. Yeah, and then, like-
[00:25:31] Matt: And water will pool, that tin could-
[00:25:33] Hamish: The tin could, yeah ...
[00:25:34] Matt: it could can or, like...
[00:25:35] David: 100%, and there's condensation, night sky radiation on the bottom of the box gutter.
[00:25:41] There's how... If you do have water underneath it, how do you drain that? Where do you drain that? How does it dry? Is it gonna drain because it's sitting at, you know, half a degree? There's so many issues with it that it's just-
[00:25:51] Matt: Yeah. If, yeah, if you waterproof it- Please avoid them ... now bring in a vapor blocker, like if you- Yeah, exactly
[00:25:56] like you start to really, uh... We, we... It's [00:26:00] ironic that the code's like, "You can't use chipboard to put your box gutter on."
[00:26:03] David: Mm.
[00:26:03] Matt: So they've identified that water's getting through and leaking, but-
[00:26:06] David: Exactly ...
[00:26:07] Matt: putting a cement sheet doesn't fix the issue. No. It just means that that material doesn't rot, but the water's gotta go somewhere.
[00:26:13] David: Yeah, and it will heat up and dry into your structure, and then you get mold risk and... Yeah.
[00:26:18] Matt: But yes, so that, that... So box gutter, we can put planter boxes there that... A planter box- It's the same, same sort of thing ... and box are the same sort
[00:26:25] David: of thing.
[00:26:25] Matt: Just literally the same thing.
[00:26:27] David: Yeah. Um, and, and I suppose sort of window design's a big one that is a point of contention that I come across- Ooh
[00:26:33] a lot.
[00:26:34] Hamish: Talk to me about that.
[00:26:35] David: Um- '
[00:26:36] Matt: Cause I feel like window design, the answers are all there
[00:26:39] David: For us, but like there's a mismatch between what appears in the code and sort of what we recommend doing
[00:26:48] Matt: So is, are, are you talking about the continuous flashing of the head?
[00:26:51] David: Yeah, stuff like that. The 110 mil, that's the essentially the snake skin around that comes attached to an alley window.
[00:26:58] Yeah. [00:27:00] That still appears in the code, and there's like some certifiers have a bug bear about it. Um-
[00:27:06] Matt: Saying that they would prefer that over your tape?
[00:27:08] David: Yeah, exactly. Wow. But it's, it's, it's verified through 4284 testing, like it's a compliant method of install, but it's that whole DTS verse.
[00:27:17] Hamish: Yeah. What's in the code and what's easy?
[00:27:19] Yeah. So talk to,
[00:27:19] Matt: talk
[00:27:19] David: to me
[00:27:20] Matt: through DTS. Quickly touch on what DTS is.
[00:27:24] David: Oh. Uh, deemed to satisfy is sort of, I mean, the way I describe it is the shittest you can build a house without going to jail. Um-
[00:27:33] Hamish: So th- so just, just for clarity- Yeah ... th- these are pathways in the NCC to comply?
[00:27:37] David: Yes.
[00:27:38] Hamish: Yeah.
[00:27:39] David: So DTS is what they outline in the NCC and through standards and stuff of compliant method of install, but it is the minimum compliance here.
[00:27:49] Matt: So, so the NCC has all the clauses and, and that's like the basics. If it doesn't fall in that, you then fall into the DTS?
[00:27:57] David: Uh, no. So DTS is the ba- [00:28:00]
[00:28:00] Matt: The basics ...
[00:28:00] David: basics, yeah.
[00:28:01] Matt: Okay.
[00:28:01] David: Then beyond that is a verification method. So each clause will have a list of test methods that you can do to verify that your system's watertight, weathertight, that sort of stuff.
[00:28:12] So that's sort of the better performing-
[00:28:15] Matt: And that's what you guys are?
[00:28:16] David: Yeah. Okay. That's pro- where we s- like we do so much testing- Yeah, I hear you. Yeah ... on our stuff. So that's sort of the avenue we generally head down. And then you have stuff like evidence of suitability, so like AVG 1 or something. Um, but that's more, you know, research articles from the States and like- Yeah
[00:28:36] saying, "Yes, I can put exterior insulation on my CLT structure- So- ... even though it's technically not deemed to satisfy."
[00:28:45] Matt: And you have kickback from builders along a lot of these things, and when you start to produce a lot of this information- Mm ... do they get it or are they like, "Well, it's your-" Definit-
[00:28:53] David: look, no one...
[00:28:54] Yeah. S- every builder knows that certifiers can sometimes be stubborn, [00:29:00] so I'll leave it at that. But like, you know, most of the time when you explain it like that to someone and you're like, "Hey, like this is a pathway, yes, but there's also the verification stuff," and you can outline it. But that's why there's a popularity of things like CodeMark and Brands appraisals because it takes away all that guessing and it's just a like green stamp that a certifier can say, "Great, don't have to look at that."
[00:29:24] Matt: Is Pro Clima stuff CodeMarked?
[00:29:27] David: Yes, mo- uh, uh, it's not a simple process 'cause they're quite diligent.
[00:29:32] Matt: Cost. It's cost.
[00:29:33] David: No, the cost isn't an issue. It, it's more just- You know, what are they code marking? And then they wanna... They'll send you a list of things that test they wanna see. Um, and it's just, you know, it's a process.
[00:29:47] It's not as easy as just going to them and throwing money at them.
[00:29:49] Matt: Yeah, do you have code mark it on your window tapes for this issue that you talk about?
[00:29:54] David: Not yet.
[00:29:55] Matt: Not yet, okay. 'Cause it, yeah, I've, I've never been pulled up on it, but- Yeah ... we, we do work a lot with Dave [00:30:00] from Permit Approvals Plus, who's been on the podcast.
[00:30:02] David: Mm.
[00:30:02] Matt: And he can quickly see that it makes sense that what we're doing compared to the snakeskin. As a building surveyor, you should be just-
[00:30:08] David: You can get a hose and see if it makes sense.
[00:30:09] Matt: Yeah, yeah, yeah. Yeah. Like, it's actually a good thing if, if you're a builder and your, your building surveyor is questioning it, just-
[00:30:15] Hamish: Go and get a hose.
[00:30:15] Matt: Yeah, go get a hose and ask him how long you want to stand there for, one, two, three hours. Say, "I'll rip out the under window, and I'll put in the snakeskin, and I'll hose that down, and then you tell me if it's compliant or not."
[00:30:26] David: Yeah. And it's also, like, that's one way to do it on, on site, but, like, at the design stage if a surveyor picks it up and they're like, "Oh, where's the code mark for this?"
[00:30:36] It can be frustrating having to explain those methods of compliance. So, you know, code mark's a good thing. There's a reason it's there, but it's, it's a process to get it, um, for everything, like window details. You can get the product code marked, but the details are a bit more complicated.
[00:30:56] Hamish: Yeah. I mean, I understand why the code does what it does.
[00:30:59] [00:31:00] Like, I get it, but the fact that it's so slow to then pick up this stuff is probably- Mm ... the most infuriating, infuriating part. Like, if we have- Yeah ... you know, if, if we're trying to protect the consumer really, 'cause that's what the code's there for- Mm ... why not put in measures like what we're just talking about now, which I think are a low-hanging fruit Yeah, I know.
[00:31:18] It's, it's like- We, we can sit here, we can re- sit here and riff
[00:31:21] Matt: about it all day ... so what's, what's sort of frustrating on that is, like, I saw when they were the VBA, they doing this study into, like, why balconies leak and why windows leaking. How about instead of spending the millions to do the study, everyone are like, "Hey, guys, got the answer."
[00:31:32] Yeah. It's 'cause they weren't using the right products, they weren't installed properly.
[00:31:35] Hamish: Yeah.
[00:31:35] Matt: Save yourself the millions in the investigation. Uh, and, and they weren't tested and verified. You, you, uh, you, you solve the problem without a study.
[00:31:43] David: Products are, are definitely a part of it, but also design and, and, like, understanding the basic concepts.
[00:31:51] Like a big one for windows leaking in commercial facades is an interior air seal, and you sort of think of that as like, oh, it's [00:32:00] not really weatherproofing. But under any sort of pressure buffeting against the structure, that's trying to equalize through your window junctions, and if you haven't sealed that properly, it's gonna pull moisture in like a vacuum cleaner.
[00:32:11] Oh. So that's what I presented on at the Air Building Thing physics conference. Yeah.
[00:32:17] Hamish: Yeah. That- The Building, the Building Thing. The
[00:32:17] David: Building Thing. But it's that concept of it's something as simple as, you know, a lot of builders, like, spray foam it to add-
[00:32:27] Matt: But what
[00:32:28] David: spray foam? ...
[00:32:28] Matt: insulation. This is a really important part.
[00:32:30] David: We can dive into that. Yeah, 'cause if you go- I'll cross my fingers ... if you
[00:32:32] Matt: do an open cell spray foam, you might be in a bit of problem.
[00:32:35] David: Totally. Um, but reality is if detail are easy, tape up your inside. If you've got tape anyway- Yeah ... you've completely moderated that pressure zone between your window junction.
[00:32:47] Matt: It's interesting, yeah, so I'm about to do a passive house, uh, and we're not using INTELLO for the first time ever.
[00:32:52] David: Okay.
[00:32:52] Matt: Should I, whether is a consideration, but n- so now I think airtightness, should I just have an extra few rolls of the [00:33:00] X-PLORA and just go around and just tape the junction just to my stud and top?
[00:33:03] David: Absolutely. Yeah, yeah,
[00:33:04] Hamish: yeah. Interesting. Yeah. 'Cause we've, we've got a project which we're about to start, which just has an external barrier.
[00:33:09] David: Mm-hmm.
[00:33:09] Hamish: And, you know, we're going for l- w- our, our goal is one, airtightness- Yeah ... which I reckon we'll get, but we haven't allowed to tape the inside.
[00:33:17] David: Yeah.
[00:33:18] Matt: It's what they
[00:33:20] Hamish: use, like- But we are foam-
[00:33:21] I'll wear that
[00:33:21] David: guy. It's, it's more important- I've allowed, I've allowed
[00:33:21] Hamish: for foaming,
[00:33:22] David: but I haven't- ... in commercial under significant pressure, like wind pressures, but it's good practice for any sort of window weatherproofing.
[00:33:29] Matt: And that's where it's gonna leak your heat
[00:33:30] David: Can I, can I ask on that though? Like, why, why the Passive House without the intel?
[00:33:35] Like-
[00:33:36] Matt: No, it's a, it's a, uh, cost.
[00:33:39] David: Yeah.
[00:33:40] Matt: Like, let's be honest, the air tightness internal membrane and batten system probably adds 45 grand to the process.
[00:33:46] David: Okay.
[00:33:47] Hamish: Same, same on this one. This one's a cost-sensitive project, and,
[00:33:49] Matt: um- And we push for it every single project.
[00:33:51] Hamish: You know, we're, we're still putting... We're still going for good air tightness- Mm
[00:33:55] so we are targeting one, good windows, or BQ PVC, and we are putting [00:34:00] a, um, ventilation, dedicated ventilation system through. Yeah.
[00:34:03] Matt: Same
[00:34:03] Hamish: here. But, um, in our climate, the risk, you know, Alex Slater's on this project, so he's done some calculations and some modeling and there's no risk of, um, uh, any cold spots in that wall.
[00:34:17] David: Yeah,
[00:34:18] Matt: okay. We got 140 walls as well. 140 walls. Yeah, that's, yeah, that's a key point. Yeah, okay. I've got 140 as well,
[00:34:21] Hamish: so-
[00:34:21] David: Yeah.
[00:34:22] Hamish: Yeah, and that's probably interesting to, interesting to, to, to, to, to sit on for a second 'cause 90 mil walls would've made a difference.
[00:34:28] David: Yeah, definitely.
[00:34:29] Hamish: Yeah.
[00:34:29] David: Yeah, it is. That would
[00:34:30] Matt: condensate.
[00:34:30] Hamish: Yeah.
[00:34:31] David: Yeah. '
[00:34:32] Hamish: Cause, 'cause we're keeping this structure warm, if we understand sort of basic building physics. Yeah. More insulation, warmer structure. So there are areas of-
[00:34:37] David: Yeah, some sort of the basics of building physics. Yeah. I think it's, like, three important envelopes to consider. There's your weather tightness envelope on the outside, and these all...
[00:34:47] Everyone's heard of the red pen with the air tightness- Yeah ... how you draw around your structure. Yeah. I've
[00:34:51] Hamish: never done that.
[00:34:52] David: Uh, it's, it looks good on presentations, but, um-
[00:34:55] Hamish: Steve presents it well, yeah. Yeah.
[00:34:55] David: But you, you should do it three times almost, like, your external weather tightness [00:35:00] envelope, your thermal envelope-
[00:35:02] Hamish: So insulation.
[00:35:03] David: Yeah.
[00:35:03] Hamish: Yeah.
[00:35:03] David: And then your air tightness envelope if you're going down that path. And your weather tightness and your air tightness can be the same thing, but I think thermal envelope's just as important as those other two because if you have these gaps and thermal bridges, it adds up so quickly, one, to the efficiency of the structure, but also the health and durability and cold spots and condensation.
[00:35:25] Matt: Yeah. Well, the NCC punishes you. If you have more than 5% gaps in the insulation layer, you lose 50% of the effective R value. So you might have put R6 in your ceiling, you got 5% gaps when you've got your heating and cooling pipes- Yeah ... and your ducts and lights and downlights, y- y- your R6 is no longer R6, it's R3.
[00:35:43] David: And it's crazy, like, you know, we're talking about five years ago I was building houses, and- I never thought about that once.
[00:35:53] Matt: Yeah.
[00:35:53] David: I was jamming in- You're not
[00:35:54] Matt: meant to know. You- you- ...
[00:35:55] David: the batts straight out of the bag, and like, it's just something I wish was more- [00:36:00]
[00:36:00] Hamish: And stuffing it into crevices and- Yeah ... and not- 100%
[00:36:03] thinking about it. Yeah.
[00:36:04] David: Yeah. And I just wish it was just something spoken about even as like a module in TAFE, is just sort of envelope design.
[00:36:12] Matt: Well, uh, uh, it's probably important to know why that doesn't work, because insulation is essentially millions and millions and millions of little bubbles.
[00:36:19] David: Mm-hmm.
[00:36:19] Matt: And if you compress those bubbles, well, they can't store-
[00:36:23] David: They... Yeah. Yeah. Exactly.
[00:36:24] Matt: They... You're
[00:36:25] David: moving them out the way. So the thermal resistance comes from trapped air pockets. Yeah. This is also another problem I have with Anticon, but I'm-
[00:36:30] Matt: Go for
[00:36:31] David: it ... dancing around.
[00:36:31] Matt: No, don't dance. Don't dance. Let's just not say Anticon.
[00:36:32] Let's say there's an- uh, just go for it. Yeah, okay. Well- Because it's used all the time. I still, I still... I know architects that listen to this podcast are still specing
[00:36:43] it.
[00:36:43] David: Mm-hmm.
[00:36:44] Matt: And it's dangerous.
[00:36:46] David: It is dangerous.
[00:36:47] Hamish: Uh- And, and, and, not o- And you're liable ... and not only that, well, there's that part, but it's also being added into your NatHERS assessment as well as- Yeah ... as part of the R-value. That's a big one. And it's not, it's actually not doing anything. Do you know what?
[00:36:57] The only good thing about Anticon [00:37:00] is that it does dull the rain when it rains.
[00:37:02] David: So I hear. I haven't seen any data on it though.
[00:37:04] Hamish: Yeah. Yeah. But like, that makes sense to me. Okay,
[00:37:06] David: so
[00:37:06] Hamish: s- I hear that, but- I have, I have anecdotal evidence of- Yeah ... um, s- you know, I guess switching six or seven years ago from building normal code build homes and using Anticon to, uh, building high performance and passive homes.
[00:37:18] Mm. And like the first couple, they're like, "Oh, we really, uh, we can... We hear the noise more." It's a different sound, 'cause your Anticon's like-
[00:37:27] Matt: Did they have internal air tightens layer?
[00:37:29] Hamish: Uh, no. Yeah,
[00:37:31] Matt: that's... Yeah.
[00:37:31] David: But if you talk to an acoustic consultant, they're never saying put- bulk insulation up there, they're saying put a rigid like FC sheet up for acoustic dampening.
[00:37:41] Hamish: Yeah.
[00:37:42] David: So the, like I'm no expert on acoustics, but there is, I think there's a fundamental misunderstanding and anecdotally and, and like intuitively that makes sense, right? You're like, "I've got a blanket under my sheet- Yeah ... it's gonna dampen it." But I don't know if that's the case. I don't-
[00:37:58] Hamish: Yeah. Well look, I mean, we're, [00:38:00] now that we're us- putting significant amounts of insulation in our roof and also from, and most projects now we're making them a warm roof.
[00:38:08] David: Mm.
[00:38:08] Hamish: So you're actually not allow- Yeah ... getting the, getting that sound to go into the attic space. Again, I'm not a- Totally ... I'm not an acoustic engineer. So, yeah. Warm,
[00:38:15] David: yeah.
[00:38:15] Hamish: But intuitively, stopping the sound from getting into here and then reverberating around.
[00:38:20] Matt: Mm.
[00:38:20] Hamish: And Cam, please like catch me out here if I'm wrong.
[00:38:23] But, um, like we're seeing a, a shift now that it's not as much of an issue.
[00:38:27] Matt: But- Yeah. I, and I don't want to go on this
[00:38:29] Hamish: road- I honestly love, honestly love hearing rain on the roof. Yeah.
[00:38:32] Matt: Same. But, but warmer roof- ... Australia's definition of a warm roof to the traditional definition of warm roof is actually very different.
[00:38:38] Hamish: Oh, true. Yeah.
[00:38:38] David: I, I think it's helpful for, you know, like an Aussie chippy or builder to just understand not having cold dead air above your insulation in your attic. Yeah. Yeah. Because we build trusses. A lot of places in the world don't build trusses. That's where the
[00:38:52] Hamish: difference is. So, so in a, in a nutshell, warm roof, pushing your insulation right up to the underside of the- Externally if you can
[00:38:57] right of the underside of the roof sheet. Mm. [00:39:00] Whereas a typical cold roof construction is insulation on top of the plaster.
[00:39:04] Matt: Yeah. Which is pretty popular. And, and in that case as well, just try a design with rafters. If you've got a gable roof, ridge beam, rafter. Yeah.
[00:39:11] Hamish: Yeah. That solves so much- Unfortunately, it, unfortunately it does become a cost thing though.
[00:39:12] So again, I think I've said this before, any truss manufacturers out there that can come up with a really good detail, and I'm thinking more about where the heel sits on top of the- I was just
[00:39:20] David: about to say the same
[00:39:20] Hamish: thing, yeah ... heel sits on top of the top plate- Reach out ... to, to increase that up. Like I, 'cause obviously your truss, and I'm using my hands here, but truss comes down in a triangle and if you've got R6 in your roof- Mm
[00:39:30] and you're stuffing it into the corner- Mm ... it ain't R6 when it gets in the corner.
[00:39:34] David: 100%.
[00:39:35] Matt: We ask all our roof trusses to have a 300 mil heel.
[00:39:37] Hamish: Yeah. Bring, bring... That's what I'm saying. Yeah, yeah, yeah. Bring the heel up. Okay, yeah. But then, but then you also need to figure out a really good efficient way to then have the insulation pushed up to the top.
[00:39:46] David: Yeah.
[00:39:46] Matt: That, that's the challenge. '
[00:39:47] Hamish: Cause you've got rafters and it holds it nice and, nice and tight. Run a couple of straps- Yeah ...
[00:39:51] David: job's done. That's a really overlooked thermal bridge, is that sort of top plate rafter connection- Yeah ... straight through there. Yep. See it often. Anticon.
[00:39:57] Matt: Anticon
[00:39:59] David: [00:40:00] is the bane of my exis- No, it's not that bad.
[00:40:04] It's-
[00:40:05] Matt: It is.
[00:40:06] David: It is. It's just one of those sort of relics that like everyone just sort of, you know, as a builder we were talking about like intuition before. You're like, "Oh yeah, that makes sense. Foil reflects it, the heat away. That's all good." The reality is it has that trapped air insulation on it- So what happens when you're, instead of having trapped air pockets, you're compressing it between a roof sheet
[00:40:31] Matt: It's no longer doing
[00:40:32] David: So now you have roof sheet compressed nothing glass fiber, foil, sometimes metal roof batten, metal truss.
[00:40:42] It's just a convection pathway, like massive thermal bridge at that point.
[00:40:47] Hamish: Yeah.
[00:40:48] David: And you've got that all over your roof structure is when you're seeing like ghosting of condensation on roofs and stuff. It's where it's hitting that. So the i- the, the way that anti-con is supposed to [00:41:00] be anti-condensation is it's supposed to keep the roof sheet warm.
[00:41:05] So during night sky radiation, you don't get condensation forming on the underside. At the points where that's now compressed, you don't have that continuous warmth, so you get that condensation occurring, and now you've got this saggy, essentially bowl of, um, wool to hold that moisture there.
[00:41:27] Matt: It's not even...
[00:41:27] So it's not wool, it's glass fiber, and it sucks and holds moisture.
[00:41:30] David: Exactly. It's not hydrophobic. And you can see it at the gutter where it hangs over into the gutter. Go-- next time you've up cleaning your gutters, check what that looks like and how much it falls apart in your hand, and how full of water it is.
[00:41:44] It, and, you know, you get, end up with things like phantom leaks 'cause all you're doing is rolling it 200 mil overlap. So when you've got that sag, and that fills up with water, and it tracks down to that overlap, you like got a leak in your kitchen, and you're looking for it for months, and you [00:42:00] can't find it.
[00:42:01] Matt: And the other thing, so it was designed for sheds.
[00:42:03] David: Yes.
[00:42:04] Matt: And somehow-
[00:42:05] David: It's probably pretty good for sheds.
[00:42:06] Matt: And actually somehow made its way into the housing because I think where the issue went along is it was a quick one point five R gain for the- Mm ... for the energy assessor.
[00:42:17] David: Yeah.
[00:42:17] Matt: To, to,
[00:42:18] David: to- Us-- I don't know if that's on the topic with Jesse, but he knows a lot about the history of the, um, where anti-con came from, and yeah.
[00:42:27] Matt: He's also very diplomatic and very-- One thing you guys about Pro Clima is you're really good at not poo-pooing other brands or companies.
[00:42:34] David: Oops.
[00:42:34] Hamish: You know what? It's, it's, it's, it's good to be like that when you know you've got the best product.
[00:42:38] Matt: Yes. Now, uh- Pressed for time.
[00:42:43] Hamish: Mm-hmm.
[00:42:44] Matt: The head to the Mindful Moment?
[00:42:46] Hamish: Yeah.
[00:42:47] Matt: So Mindful Moment, uh, our great friends at MEGT, Australia's leading apprenticeship experts. Now, Dave, the whole idea of this segment is to maybe give advice to someone, I shouldn't say [00:43:00] young anymore, because the government are trying to introduce 50-year-old apprentices into the industry. Um, so anyone doing their apprenticeship-
[00:43:06] Hamish: 50 is young.
[00:43:07] Matt: Yes. So yeah, so by the time you finish your apprenticeship, you're 55 looking to retire. So someone might be coming into the industry, uh, and we're generally trying to find bits of, uh, nuggets of gold that they can progress their, their career to do better. We've had people explain that they did their Cert IV or diploma as a third year.
[00:43:27] Now, I'd love to hear a little bit more on, and give some advice from your perspective of carpentry was the base of what you did.
[00:43:35] David: Hmm. Carpentry gives you, first and foremost, like the most grounded and intuitive understanding of engineering, physics, and everything, because you're putting it up, you're s- feeling what works and what doesn't work, you know?
[00:43:49] It's... And you, you sort of make mistakes along the way, and it gives you that sort of opportunity to grow.
[00:43:55] Hamish: Well, it's instant feedback, is what it is.
[00:43:57] David: Instant feedback. Yeah. Absolutely. Yeah. So I [00:44:00] think that's like just a huge, like, benefit to sort of have that exposure and experience at, at a younger age or 50.
[00:44:08] Yeah. Um,
[00:44:09] Hamish: and- I think, so, so what, so Vili is obviously an incredibly intelligent human being, right? And I definitely got that, and, and I understand that you guys kind of- Dave's not ... have a sort of a similar... Sorry?
[00:44:20] Matt: Dave's not.
[00:44:21] Hamish: Da- k- now hear me out here. No. Try- trying, uh, you guys kind of have a similar role.
[00:44:25] However, the conversations that we're having today just feel different because you've got this understanding of how the things go together.
[00:44:31] David: Mm.
[00:44:32] Hamish: And, and I'm not saying that, you know, one's better than the other.
[00:44:35] David: No, it's-
[00:44:35] Hamish: But it's, but it's a different con-
[00:44:36] David: Epic to have both and- But it's a- ... sit next to each other
[00:44:38] Hamish: it's a different- Damn it, Robin ... it's a different conversation, and, you know, having a chat with you today kind of allows me to kind of understand it from maybe a more accessible use of language than- Mm ... say, when Vili's explaining something.
[00:44:52] David: Brownie in motion or whatever.
[00:44:53] Hamish: Do you know what? Yeah, Br- yeah, and look, I get all of that too, and, uh, we've, we've got the benefit of having done this podcast for a while now and been interested in the stuff, [00:45:00] but- Yeah
[00:45:00] I think having, uh, having a carpentry background for me is a couple of things, right? One, it's just that satisfaction of being able to do stuff, you know? Mm. And although my wife is constantly on my case to chan- change handles in the house- A- anyway, that's a whole other, a whole other story. But the thing is, if I wanted to, I could- Oh, no, we'll
[00:45:18] Matt: go down that avenue.
[00:45:19] Hamish: No, I ca- I can. I can change it if I wanted to. Yeah. But I can also jump on the, you know, put the tool belt on on the weekend and build a, build an alfresco.
[00:45:26] David: Yeah.
[00:45:27] Hamish: But then I can also jump in here and do a podcast. I can also go and do that. Mm. You have then decided to take that next step, get further educated, and then come into a role which was almost made for you.
[00:45:37] David: Mm.
[00:45:37] Hamish: I guess the whole idea of this Energy Mindful Moment is just for people to see that it doesn't just stop at carpentry. Like, there's so many other opportunities for it to come from, but such a great building block.
[00:45:47] David: Yeah, absolutely. And I think what's really, really cool as well from what I've been doing is when you talk to the young chippies coming through, or, like, even apprentices and stuff, there's such an [00:46:00] eagerness from them to, like, build better and understand.
[00:46:03] And yes, it's probably, like, the crowds I'm speaking to, but I really get that impression. Like, even my mates who are still building, when I'm having a beer at the pub with them talking about it, their, like, eyes light up.
[00:46:13] Matt: So if you're an apprentice or a carpenter or any trade, and go, "Oh, we don't use building physics the way we build," if you get two 90 by 45 timbers and you laminate them with some, some framing nails to get up- You're an engineer,
[00:46:25] Hamish: baby
[00:46:25] Matt: that's, that's called physics. Yeah. That's changing the structure of the timber. Yeah. So you are doing it every single day at work, screwing some ply to the building. Yeah. That's building physics.
[00:46:34] Hamish: But, but then also the houses that you build, building physics exists there. Yeah. You're
[00:46:39] David: creating an environment that- And it always has, and whether you've, like, been internalising it or not, you're developing an intuition for it, you know?
[00:46:46] Like, basic things like, you know, where, what windows you're using, where you're putting your insulation, thinking your anticont is doing something. It's not seeing that sweating in the building when you're building, all that stuff.
[00:46:58] Hamish: A- a- and even just knowing if you're a renovation [00:47:00] carpenter, you just know that if you're removing cladding from around a window-
[00:47:03] David: Mm-hmm
[00:47:04] Hamish: there's a really good chance you're gonna see rot there.
[00:47:05] David: There's a very good chance.
[00:47:06] Hamish: So you have been exposed to building physics and the- Yeah, yeah ... impacts of not managing it.
[00:47:11] David: Yeah. Yeah. So yeah, I think it, it's exciting to see the eagerness coming up with the new generation. I hope it brings more people into the trade because I think it's- Yeah
[00:47:22] super important. Yeah.
[00:47:24] Hamish: Um, Dave- Dave ... thank you. Thanks for coming along, man.
[00:47:26] David: Pleasure, guys. Thank you.