High-performance building is not just about premium products. It is about the system. In this episode, we sit down with Sven Maxa from Maxa Design to unpack what Passive House building really looks like behind the scenes, from airtightness targets to the practical realities of delivering high-performance homes on site.

This conversation flips the usual format, with Sven taking the lead and putting us (Hamish and Matt) in the hot seat. We get into the details that actually make or break a Passive House project, including airtightness testing, verification, contract clarity, and what happens when documentation looks great in renders but does not hold up on a building site.

A major theme is collaboration between the architect, designer, builder, and trades. Passive House and building science only works when the whole team is aligned early, with transparent cost planning, clear communication, and strong documentation to avoid rework, delays, and budget blowouts.

We wrap by looking at what needs to change in the Australian construction industry to lift standards at scale. Better legislation, better education, and a stronger baseline for residential construction.

👇 CHAPTER MARKERS 👇

00:00 Introduction

02:18 Meet the Sponsors - Proclima

03:05 Builder's Perspective on Passive House Contracts

06:39 High Performance Homes: Products vs. Systems

14:48 The Importance of Collaboration in Construction

23:20 Challenges in Project Costing and Documentation

36:51 Feasibility Studies and Square Meter Rates

40:13 Site Inspections and Builder Reactions

41:07 Quality Control on Site Visits

41:57 Site Meeting Schedules and Coordination

43:06 Importance of Passive House Principles

44:50 Challenges in Australian Building Practices

48:54 Air Tightness and Building Performance

56:45 Biggest Mistakes and Lessons Learned

01:03:38 Favourite Projects and Memorable Builds

01:13:43 Future of Residential Construction

01:20:46 Mindful Moments for Apprentices

LINKS:

Connect with Sven:

Maxa Design

Our Sponsors:

Proclima - https://mindful-builder.captivate.fm/proclima

MEGT - https://mindful-builder.captivate.fm/megt

Connect with us on Instagram: @themindfulbuilderpod

Connect with Hamish:

Instagram: @sanctumhomes

Website: www.yoursanctum.com.au/

Connect with Matt:

Instagram: @carlandconstructions

Website: www.carlandconstructions.com/

Mentioned in this episode:

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We truly appreciate you and now onto this week's episode.

This sounds different, doesn't it?

Welcome to the Mindful Builder Podcast, and I'm not your host.

No, but except for today, where the hosts have graciously agreed to flip the script.

And let me ask the questions.

So hold on tight.

We are in for a ride.

This feel like a radio announcer.

I feel

like I'm like one of those Carney carnivals and the

Carneys like you about to jump.

So quick introduction.

I'm VE Maxa, founder of Maxa Design here in Australia.

We specialize in high performance residential design, working right at the

intersection of building science, climate responsive design, and the realities

of actually getting these homes built.

Today I'll be putting the questions to these two gentlemen, drawing on

their experience as builders and communicators in this space, and

hopefully teasing out some insights that are genuinely useful for designers,

builders, and home owners alike.

So let's crack on first a message for us sponsors.

Uh, before you go, Matt, I'm gonna call Dawn after this and I'm gonna ask how

many, how long spend spent in front of the bathroom mirror reading that

script because that was brilliant.

So we are coming from the built to last pro climber studios.

Proli is our major sponsor, which we are both Hamish and I.

This fan is super proud to, um, have on board.

Like this podcast costs us a lot of money, but these guys are now

being able to assist us at least cover a few costs here and there.

Um, we are going across Australia this year to record some podcasts as well.

We are,

so we're gonna be hitting a number of states, so stay tuned.

Where are we going?

We're going to wa

now that you are, now that you're part of the

group, we're gonna wa we are going to Adelaide.

We are going to Brisbane.

We are going to Sydney twice.

Yep.

So yeah,

maybe Tazzie.

Maybe Tazzie.

Maybe Tazzie.

Ooh, awesome.

Maybe

Tasie.

I've got a list of questions here.

And is there a buzzer?

Yeah, you'll need it.

So, and my screen's gonna keep turning off on me.

I was reflecting on one of our previous conversations in one of these podcast

chats we did, and I'm pretty sure both of you said at the time, and it changed,

that neither of you as builders would sign a contract, a building contract

to deliver a certified passive house.

Mm-hmm.

Now we know you've built them, we know you're good at it, and

you're very confident builders.

But you wouldn't sign a contract for one.

No.

And I wanted to delve into that a little bit because I know you're both

very competent with air tightness, HRV systems, great windows, et cetera.

Tell me what the, what the deal is.

You go first.

I will sign off on one, but I'll sign off the, I will hit 0.6.

That's it.

Why is it my responsibility of the builder?

Like how if I say, Hey, I'm gonna deliver you a certified passive

house in the contract, how do I then check off that you've got all your

design right from it, or just, let's assume you're doing the modeling.

Mm-hmm.

How do I sign off on that Now?

I would sign off if we had a precon pre-construction, say from Marcus or

Amelia or Luke to say, certified if, if everything is built as per PHPP.

Yep.

And you deliver that.

Yeah.

Sweet.

I'll sign that off.

Great.

But I'm not gonna sign off something.

That was a point I needed to clarify.

Yeah.

Are you the

same?

So I I'd be the same.

I, I would say yes, I would put it into my contract, but it

would just come with conditions.

Yeah.

So it's something we advocate to our clients, right.

That if they're gonna invest the money in great documentation, passive

house calcs, pre-construction checks, checks, certification fees, et cetera,

and they're using an experienced, reputable builder who's done it before.

Mm-hmm.

What's the barrier?

So I look at it from a.

There's like a risk point of view.

Like I, I'll go back to my first ever contract that I signed, I wrote in a

stupidly in hindsight, that I would.

Build your passive house.

So like hypothetically, I think it was at the conference, it was a project that they

wouldn't give them the final building.

This was one of

your projects.

It's, it was one of our,

so what if I, what if I, what if I can't claim for six months my final payment,

the client's allowed to move in, do I get hit with liquid aid damages?

So I think there's gotta be a little bit of a point there where I

gotta protect myself as a business.

The passive house part isn't easy, it's all the actual other legal

crap that would probably come with it that I'm protecting myself from.

And payment terms.

Yep.

Which you could structure appropriately.

A

hundred percent.

Yeah.

So, so again, to summarize that, I would with conditions.

Mm, yep.

Okay.

And the conditions are.

Adjusted payment terms.

Yep.

Potentially.

Yep.

To, to that, that if there's something outside of my direct control that it

doesn't get certified for maybe the,

yeah.

If someone made a wrong calculation

Yep, yep.

That, that's not on me, then that, that shouldn't, you know, but,

but then here's the, here's the other kind of flip side of it.

We go back to that Jan Jack project.

What happens if the building survey doesn't issue the C of O?

Yeah.

Well in, in that scenario, there were a lot of hurdles, but it got done because

everything was evidenced appropriately.

Yeah.

Yeah.

And that was a first time builder who'd never built a passive house.

So yeah.

Is it a really interesting, it was a complete, um, digression

by the building surveyor.

They, they went down a road they didn't need to go down, but lack of education

and maturity in the market Yeah.

Led us into that

position.

Yeah.

We need, we need a pre-construction sign off from one of the certifiers.

Absolutely.

Yes.

Sweet.

That's cool.

Yeah.

I mean, as you guys know, we, we don't do that without, but

it's just one of those things.

So, um, okay.

Next question.

We've got lots right

time anyway.

We can split into two podcasts if we need to.

Love it.

High performance as a system.

So at what point does high performance, inverted commas stop being about products?

And start becoming a system discipline.

Where do you see most projects quietly falling short.

This is a interest, it's a really good one because high performance

gets thrown around a lot.

Yeah, it does.

And passive house does as well.

But passive house is very clear with what it is.

Mm-hmm.

We don't have a clear universal definition of what high performance is.

We've kind of made it up in our space,

but we driven it like on social media through Instagram,

whether just whether it's Max, it doesn't matter, like, but,

but, but the, the people building high performance homes, they're

calling it a high performance home.

I know for us internally, a high performance home is a passive

house that's not certified.

So some of the things that we tick off, that we call a high performance home

is that absolutely has to be modeled.

In pre-construction in PHPP.

Mm-hmm.

What if it's modeled through Nat Hers and it's a, like, it's hitting say, 8.5 stars.

All I'm talking about is what we do internally.

Keep taking my

questions

away.

I'm the host.

I can't

No, because I agree with you.

I can't, I can't talk to what other people do or what other steps should they take.

But this is just what we do.

Yeah.

Has to be modeled internally.

Agree.

Uh, from sanctum home's point of view, we need to make sure

that we're making it airtight.

We're putting good, uh, the pro climber system on.

Sometimes we're not putting internal barriers.

Yep.

Though, however, what we're doing in that scenario is double checking with

someone like Cameron Mun Monroe to make sure that we don't have any risk.

Yep.

We're going through this at the moment with project that we're

working on together, where we've identified there could be a risk.

So we're getting a wolf analysis.

So modeling's really important.

Mm-hmm.

Continuous simulation, high performance windows, airtight structure.

Uh, HIV Mm. All the same principles that we're putting into a passive house.

Yep.

Yep.

The, the major difference for us is that we're.

We would consider a high performance home, uh, that's sitting within the PHI

low energy territory for most new homes.

So if we're hitting under that 30 kilowatt hour mark and we're getting better

than one air change an hour, the other thing that we think needs to be layered

on to, uh, a high performance home is all the documentation of the project.

So that's something we do internally anyway.

We're taking photos for Instagram, social media, but we're also taking

them to document the project so we can prove that we've done the things.

So that, just to interrogate that a little bit,

can I add one more thing?

Fine.

Well, like documentation, but, and which goes down to your testing and checking.

Yeah.

Like you gotta test and verify what you've done.

I think like just, and he kind of, Hamish alluded to

it and that, that actually delves a bit into what I was about to ask about,

because that's about system and process.

Is it?

Or is it just like how it should be done?

Well, no, but it, it's, it's a, it's a a step you have to go through physically to

ensure you're delivering something, right?

Whereas you've, Hamish have just talked about, um, materials, right?

And you are putting in A HRV and you're using proclama wraps, et cetera.

Yeah.

So let's say you get, um, a code compliant home, 90 studs, 2.5

wall bats, class four membranes.

Yep.

Are you going to build that as it is and deliver that to a client, but

integrate special steps or processes into your building methodologies to ensure

it delivers the best quality it can.

So you're talking about

say, or that you gonna substitute out and bring in those materials and

products?

Materials a key point.

So let's talk about, and I'm like, I'm very.

Yes.

Pro climber sponsor this podcast.

And so, and there's a reason why both Hamish and I wanted to have them on as a

sponsor because we believe in the product.

Yep.

Now we can talk about, and I'll be open here and I'll be very, if I don't like

something pro climber do, I'll be honest and say that like I don't align with that.

Yep.

Just because they're a sponsor doesn't mean I can't be

critical at certain points.

I use them because a system works.

Mm-hmm.

It's a system that's tried and tested.

There's other Class four of vapor barriers on the Yeah.

Or weather barriers on the, the market.

How many of them could sit there and put a water pressure test if

we hose down the house and work?

And that comes down to when we test a building, we'll constantly test window

openings to see if they're leaking.

Yeah.

Yeah.

Will another product be able to withstand the amount of water

that we can push against it?

And yes.

That might be an unrealistic, uh, I don't know, test that you're never

gonna see the amount of water.

Mm-hmm.

I don't know that that won't see the amount of water in its lifetime.

So yes, it does come down a certain product.

On the market because they're the only ones here in Australia that

actually can do what we actually need.

Can

I,

can I ask, go back to mm-hmm.

So what, what was the original question?

So you, you are saying you wanna go beyond the products?

Well, I'm, I'm, yeah.

I'm saying at what point does high performance stop being about the

products themselves and become the way we build the system and Oh, yeah.

Yeah.

And the techniques.

And methods.

And skills,

yeah.

So I would love for high performance just not to be relevant anymore.

Mm-hmm.

So then it just becomes that where, oh, you're building a home.

Okay, great.

And it does include one 40 starts or good insulation, and it does include

thermal bridge free construction, including your windows that it's airtight

and we've got HIV and it's healthy.

Like I'd love for it to not be called high performance anymore.

And then it's just normal.

It's such a shit word too.

I don't know.

I just don't like high performance.

Well, it's of above code.

It's, it's like saying passive house principles, like, well,

which principles are you choosing?

Right?

Yeah.

Like, it's kind of saying we're doing something above code, but it's a

bit vague exactly what we're doing.

I kind of think.

Like you kind of, now I'm just thinking out loud.

With high performance, like we say, we test, test and check at ham.

Yeah, yeah.

Where it's me and you testing on our team, like shouldn't,

wouldn't it make more sense if you don't go down the certified road?

Let's assume F's designed it.

Hey, F needs to be there for the blower at door test.

He needs to be there pre plaster.

He needs to be there when the window digs on so he can also verify it.

'cause who's to say that?

We can't just say, yeah, Tess was good.

See you later.

So that there is a segue into something that we do with our projects is we ask

our clients to engage us to conduct inspections of the passive house criteria

because you guys are very experienced.

You know what you're doing.

It's highly unlikely you'll ever make a mistake or you,

you'll divert off the drawings.

I've made mistakes.

Some people do, right?

And so I've forgot to

document stuff.

We've had two, the first two projects did this on the first one.

Um, we stood at a junction of a wall and a window and a step in the floor with

the builder for half an hour, I reckon.

Something didn't feel right, it just, we didn't know what it was.

We just kept coming back to that corner and in the end, Atan our senior

architect, he's looked and he's gone.

That's a thermal bridge, you know, we didn't have it on the document.

We'd missed it.

The certifier had missed it.

Our passive house designer missed it.

We then worked chopped it on site.

He brought out his concrete saw.

He said that there has probably saved me tens of thousands of dollars

finding it now rather than finding it once the joinery goes in and working

it out, or the frame goes up or whatever, having to rebuild the frame.

So that was a win.

Second project, literally the next week we've gone out and done the inspection

for the client to make sure it's been built per the code and per the

plans, a wall was 600 mil outta whack,

right?

Our fees have just been paid for

600 mil out of,

out of a, it was in the wrong place.

The concrete slab was being poured and the wall okay, and the, the

alignment of the wall and the slab was 600 mil in the wrong direction.

So the room was the wrong size.

Now that, you know, you can put that down to a concrete.

That's a, not a passive casting

though.

No, no.

But that was just the benefit of having the designer come and

check what was going on on site.

And these builders that we're working with on these projects are fantastic builders.

They're just like you guys.

Yeah.

But they're also human beings.

Exactly.

Exactly.

Yeah.

So I mean, I, I, I try trying to kind of get the angle of where you're

going to with this, because I think it's a really great conversation.

Um,

are you sort of advocating for.

Uh, the design team to be actively involved during construction

because we, we, we support it a lot.

Yeah, we support it.

I've got another question around that now.

Okay.

I'm now, now I'm i'll.

I dunno if this is also going in, but we are now saying to clients that we

are riding in, if it's a HIA contract, we're gonna ride in ESE team and

assume that you are gonna need them to come on site a 12 month project.

Once a month.

It'd be some months, it might be four weeks in a row.

Yeah.

At certain points we might not see them for three months.

I actually just locked the gates when the designer asks to go and visit.

Yeah.

Thanks.

That was great.

Did you?

He called me last week while I wasn't on site and he goes, oh, can I go in?

I'm like, no.

Yeah.

To, to, to in breach of my like, oh, it was the right

decision.

Absolutely the right decision.

I would've let you on.

Yeah.

Thanks.

So, uh, no, that was good.

Um, so

the team approach, you guys are a massive advocate for this.

I know Builder had paid as a consultant, et cetera.

So from your perspective as builders, at what point does a project

stop being a builder, delivering a design and start becoming a

genuinely collaborative team Effort?

At what point

before the project's even started?

Yeah,

like before that is even on pen and paper.

Yeah.

So then I'll just quickly give you the sort of basic steps that a lot of

projects follow in the one we follow, we do a feasibility study first.

Yeah.

And that doesn't include a builder in that process.

Typically

that's you.

So that's you trying to get the project so you can design it.

Is that my understanding?

It's, it's almost like a concept design stage.

Yeah.

Without heavy architectural input.

Yeah.

It's more pragmatic.

What is feasible for this, this client and what they want

to do and can they afford it?

And what are the planning restrictions, et cetera.

Think that's too late.

And then we use a, a pro calc assessment on that and we sort of

sanity test that with some recent project completions and square meter

rates and whatever else we use.

Don't lock me down on square meter.

Right.

We'll talk about that in a minute.

And then once we get to concept design stage where we start building

a 3D model, that's when we would bring you guys in to start eking

out some precision and accuracy and

Yeah, so, so it's no secret that we've done heaps of projects together.

Mm-hmm.

We've got a number of projects in pre-construction.

We've got one under construction at the moment.

Uh, I'm going back to, uh, an example of a project that actually didn't go

ahead and, uh, one of your team emailed me the pro calc that you guys had

done, and I said, don't show them that

I remember this.

Yeah.

I said, don't.

I said, don't show them that.

And I'll, and I, and I, this is, these are the reasons why, and I know you and

I have talked about this a lot, right?

Yeah.

And I, and I, I think pro calcs a really powerful tool, but it's like

everything good input in good input out shit, input in should input out.

Yep.

Now, I'm not saying that.

Your team doesn't get it right.

I'm not saying that at all.

And I've seen them drive it and you know, there has been some

scenarios where we've both come pretty close 'cause we use pro calc.

But I think in that particular project, my opinion and my take, my

understanding of what was involved in that project was wildly different

to the outputs that you guys got.

Yep.

So I actually told you, your team not to put that in front of the client

and I jumped in and said, I think you need to tell 'em this range instead.

Yep.

I think that And for the record,

yeah,

we did.

You did.

Absolutely.

We did.

But, but I think this, this, this, that right there is truly collaboration because

we've worked together so many times.

Yeah.

I even had a conversation with yesterday and I actually messaged

you afterwards and said, oh look.

I'm really sorry if I came across as a dick then, 'cause I basically told you not

to put something in front of the client.

'cause I think it's misleading and confusing.

Yeah.

And my reasons are X, y, and Z and we kind of agreed

mm-hmm.

That, that, that that was the case.

And I think that's collaboration.

It is

because we kind of under hard

conversations.

Yeah.

Hard conversations.

But you know, I've known Finn for

10

years, lost count,

eight, nine years, whatever it is.

So we can have those conversations.

I just don't think architects and should, designers should

show or give budgets period.

I don't think they should talk any, like I, I think that if they've got a design to

a budget and clients aren't always willing to give the full amount they wanna spend.

So that's a challenge that you and architects, designers have to face.

Once it comes down to you've got a design.

I don't think that an architect or building design or anyone other than

a builder should be giving pricing.

Now architects will go get caught on.

I don't think architects.

I'll go wide in a second.

I don't think architects should be getting quantity surveys.

'cause let's just be straighter honest.

They get quantity surveys to justify their fee.

That's it.

That's like it's period.

Why they do it.

They don't what what we need to worry

debatable.

Yeah.

It, it is totally debatable.

But, but we're also, we're also sitting on different sides of the fences.

Yeah.

Yeah.

I, I i one because I think that we, there's

also two of us too here, so

we Yeah.

Like, you know, we're teaming up on you.

Yeah.

It's like you don't know what the builder's margins are and like, you

might be better at some, but a lot of what we see is a lot of people will

try get a project across the line at a number that, that they want because

they wanna keep the job moving.

You might be better at saying no you can't do that and you can only design

to what they have told you as well.

So if they want this certain size and this amount and you know, their budget's

not gonna be realistic and then you give them a number that's not your,

also your fault that you've had to design something that they can't afford.

And I think, I think we have a responsibility to talk numbers with

the clients and it's not necessarily that we're preaching to be correct.

But like for example, I've just come from a prospective client meeting

now, just sat down, had a coffee and a chat about what they want to do.

They're talking about spending a certain amount of money and it would

be remiss of me to sign a contract and service them if I don't think what they

want to do is even remotely possible.

That's

that's different to giving a number further design

that you've designed though.

Yeah.

And so then I have to evidence my opinion

and the evidence should come from the builder,

ideally.

Yep.

Yeah.

Yep.

But the builder can't price anything realistically until he's got

some sort of design information.

But neither can you.

No.

So we are, we are using the numbers from our previous projects Yeah.

To inform what we're doing.

And that's based on

is that indexed.

That's previous.

Yeah,

yeah, yeah.

So that's historical data.

Yeah.

Yep.

And so then we have to then forecast future inflations and contingencies and

landscape budgets and all these things.

I, I think, I think that is okay at that very point in time.

My opinion is that once you've done, once there's actually some lines on a paper.

Yeah.

I, I, my personal opinion is that it can get a bit dangerous if the designer is

at that point giving them costing advice

because it becomes not our problem.

How do we get so deep into costing here?

When I was talking about, because no one wants to talk collaboration.

No one wants to talk about costing.

But I think that, I think it's a great segue into collaboration though.

It, it's a, it's a fundamental part of collaboration.

No.

Your job, like, your, your perspective I think is you should be involved

from the minute the inquiry comes in and, and the project,

not once you've signed it.

They, I think at that point, once you've signed a, you should be

interviewing, say three builders, and then they pick who they want.

I think

they Okay.

But then you are happy to get involved at that point.

But you're also able to get involved a bit later.

Uh, look, I mean, my preference is that we're all, we're all

get signed up at the same time.

Mm. Yeah.

That's my preference.

I mean, how many projects have we done together where they've come

to me, you've got signed up and then the, the project I was talking

about before was a classic example.

They came to us first.

Yeah.

They hadn't even signed us up.

Yeah.

When I was kind of giving the, like we, we were talking a lot

in that very early design stage.

Yeah.

I had never been signed up by the client yet, but I knew it was a

valuable, valuable input from me at that point in time because I knew

that that project had risk around it.

Yeah.

And I mean it ultimately,

yeah,

it just didn't make sense for them to go ahead.

Mm. It's not fair to put all the pressure on the design team either.

Like you guys know how to design.

Mm. And builders know how to build, they know buildability, but we also

sit in front of estimations constantly.

Yep.

I still dunno what something costs and I look at it.

Five times a week.

So how then not, can I think that's appropriate to put the pressure on a

design team to then also know as much as we might know about costings when

they might look at it once a year?

Yeah, I mean, I can see from both sides.

Those from, I totally get it.

I understand it.

Okay, so that's probably a answers the next question to some degree, but when

projects are run in silos and there's no collaboration, is cost overrun the

biggest issue you see on projects?

I dunno, I, I a as in, as in,

so, you know, a project is designed, it's documented, you price it, I got, I got the

answer, or then you build it or whatever.

Like what's the biggest issue you see when it isn't a collaborative

fucking shit?

Documentation by

design team?

Like straight up.

I mean there's, there's, that's my next question.

There's probably, there's probably multiple things.

One, one there's budget.

Yeah.

Uh, two.

And, and the biggest one that, the biggest thing around.

Budget at that point is that the clients are fallen in love with

the thing that's in front of them.

Yeah.

They've selected the tiles, they've selected, they have so much

emotional energy and time and money has gone into those documentation.

Yeah, yeah,

yeah.

And then the builder comes along and goes, you can't afford that.

Mm.

But also the crap document.

So is the bigger, biggest risk that the client can't afford what they want and

have requested and that the architect is delivered or that you are disappointing

the client with bad news and you look bad?

Well, it's, I mean, I think

it's all of it.

I think it's all of it.

I mean, and Okay.

Say hypothetically speaking, if that scenario was, say you came to me

and said, for whatever reason we are coming in right at the end, the other

builder had got sick and can't do the project, you are coming to me.

We would cost it, but then we wouldn't actually start that project until we've

actually gone through that documentation to make sure that the plans are right.

So it wouldn't even hit site before we've done our, uh, I guess due

diligence on that documentation.

But it, it is, it is frustrating to go back and, and

retrospectively change the design.

Oh.

For

everybody.

For everyone.

Like when it's an iterative, iterative thing and you're just

changing little bits here and there

mm-hmm.

Like, it is so much easier, so much more timely.

Mm-hmm.

Less energy, less emotion, less money.

Client pace for it at the end of the day.

So let's assume the project goes ahead.

Yep.

Are there any problems or challenges that you see when you haven't

been collaborating on the project?

Project?

Just poor document, like

quality documentation.

I have, I mean, and, and performance too.

Like h how, how, like, have all those, um, thermal bridges been analyzed, has

the installation of the windows, and has any consideration been done around that?

It's documented.

So that's one of the big, big risks for the clients, potentially.

Well,

and the

builder

scenario,

I'm assume with your comment there, em that they've got Logic House windows.

Who Harley's gonna design it.

You've Cam's already done the PHPP and it's been ticked off.

So like in best case situation,

yeah,

it's still, and it's probably bad because it's then a passive house.

So documentation needs to be on point.

The problem that I see is I get some final set of plans that meant,

Hey, can you tender for this?

There's more pages of fucking renders than there are document, like actual drawings.

Like that's,

well, you can work it out.

You're

a smart man.

Stupid though.

No, but like it's, and then I get some plans and like, like I've got

some plans on my desk set of concepts and there's more information in that

than I do that are final set of plans.

Do, do, do you know, it's actually easier for us to cost and we'd

probably get pretty close to being accurate on a set of concept

drawings and schematic engineering.

Yeah.

Because we're just going through and going, well we know there's

a tap, we know there's a tile.

We know how many square meters of whatever there is.

Yeah.

But we can move through that so quickly.

Because we're just putting allowances everywhere.

Too

many pages.

Okay.

So

that's,

that's taking me to my next question.

Too many documents.

I bring it to one PDF.

Like why, why can't the have an architectural that's also

at the same PD as engineering?

That then you put your schedules in and your why can't just be one document

and, and building a house is hard.

Why make it fucking harder by just overloading everyone with

just more useless documentation?

Yeah.

Like 40

pages of renders that

like, righto.

Give us

a 3D drawing.

Okay.

It gets that calm voice.

Architects are designers.

Jeez.

So my question was gonna be how much easier does good documentation

actually make your life as a builder?

Maybe the question should be, what is good documentation for I'm

all 3D design, like BMX files.

Like we are in the like, so going back the store back a little while,

my team were on their phone, on site.

I was like, guys, what are you doing?

They're sitting there on the models being like, well, that's how the plans aren't.

That sort of, we can't understand how they wanted it.

So we're looking, they're zooming in on the model, being like, oh wow.

I can see.

That's kind of how they want it.

That's how we'll build it.

3D models to me is everything.

'cause also we constantly get plans where you got little bits jutting in and out.

The elevations don't tell a full story sometimes.

So we can actually see how a structure might come together

from a visual 3D perspective.

So for you, good documentation is a BIM X file,

not just bim, it's, it's, it's, it's just

a 3D model.

Yeah.

I think, I think if but a

live one that he can on

site with

a tablet or Yeah,

that's mx

whatever it's Yeah.

Yeah.

Big, big winner.

You guys build in 3D now?

Yeah.

Yeah.

So why can't we just have some form of a way on an iPad to be able to access it?

Yeah.

Can, I mean, we've talked about this and maybe we're digressing a

tiny bit because I, I think I showed something on Instagram one day about

the modeling that we're now doing, and you asked, well, what about our model?

And I think I, I came, I came back to you and said, well, how you've designed

it may not be exactly how we're building it, because we're actually building the

model, how we're building it on site.

Now, I'm not saying that that can't exist.

I'm, I'm not saying that we can't bring those two together 'cause

it's much less work for us then.

It's probably gonna be more work for our, both of us in pre-con

and so there's potentially less of a gap between those two things.

If your architectural team has some really, you know, good deep

building knowledge, construction, buildability experience, et cetera.

One of the reasons we've put our team out on one of your sites recently.

Yeah.

So the que I, another thing with documentation kind of, sort of flows into

that a little bit is like, ask the builder what building site they wanna work with

and what engineer they wanna work with.

It goes a long way, huge way.

'cause we know how each other works.

Mm-hmm.

We know what the expectation are from that building survey and we

know the expectation of that engineer and what we're gonna receive.

I think the buildings survey is probably less important to me than the engineer.

Yeah.

The engineers are, are a critical component and we've

had good ones and bad ones.

As you know, we only really work with Asher these days, but yeah,

I, I'd hate other and not,

no, I don't, I don't have

strong word.

Yeah.

Yeah.

Okay.

So then let's just boil this down a little bit.

What separates.

Average documentation, just working off physical plans.

Let's ignore 3D models.

What separates average documents from really good documents?

I usually base mine off how many phone calls I get

as in the construction teams on site.

Yeah, yeah, yeah,

yeah, yeah.

So let's say you are tendering, you're quoting for a job and

you are, that's when you really pouring over the drawings, right?

Yep.

What makes good set?

What makes a, I love color.

Color.

Color, like, so I've seen plans recently, so if they've got a

one 40 mil wall with say, a 45 vertical batten, that might be pink.

If they've then got a, a cross batten as well as the vertical,

that whole wall might be yellow.

Mm-hmm.

So then you've got your 90 mil wall that might be green.

So visually, team on site.

Oh, that's the buildup for that wall.

Mm-hmm.

That's the buildup.

And so yes, it looks all different on the outside, but you see everything.

Then you've got like your engineering, when you've got say, uh, like sort of a,

is it a schematic 3D sort of that you get?

Yeah.

Like why can't that be in check checking Actually that the engineering

fits in the building is, well,

you know what?

I think understanding where all of your, um, running measurements are taken from.

Mm-hmm.

Is it outside of cladding?

Is it frame, is it slab?

Like, just understanding where that number's coming from.

Yep.

Your data point.

Yeah.

Like, and, and being very explicit about that.

Like, we like to work to frame.

You have to work to frame.

Yeah, we, we like to work to frame, but I know that's

what you're essentially starting with, isn't it?

You know?

Well, I've had a set of documents that isn't, it's like to to outside

of cladding, I'm like, well,

what's your buildup?

Yeah, exactly.

Exactly.

Yeah.

Yeah.

That's, that's

to frame.

But can I ask you a question here?

And this is

because I'm the host,

but No,

no.

Matt, he's the host.

Matt, have you got a question?

How does it go so different, like you get taught how to, when you train

to be a designer that you get set out from say a frame or something.

Yeah.

How do some people start from plaster and some are cladding and some are frame.

Yeah.

How does that all,

I, I dunno,

where does that get lost?

Yeah.

And I think it's been lost in the transition to 3D modeling.

Okay.

To be honest with you.

Yeah.

Okay.

Because we, we, back in the old manual days, that's how I started.

You, you would only really draw the stud frames.

Yeah.

You know, you can draw the plaster.

Okay.

Did

you used to go home with blue fingers from all, from the, um,

blueprints that you were drawing on?

No.

No, no.

I didn't.

Gray from the pencil.

Yeah.

Yeah.

But not blue.

Sorry.

Did they have pencils back then?

Uh, grid lines.

Grid lines.

Finn,

I love grid lines.

Grid lines that translate from architecturals to engineering.

Yep.

And that they're exactly the fucking same.

Yeah.

Yeah, yeah, yeah.

Yep.

Okay.

No, that's good.

Good feedback, gents.

Thank you.

So does a good set of quality architectural and structural documents

help curtail cost variations and therefore reduce project cost risk?

Of course it does.

I mean, is that a loaded question

to a, to a degree it is.

So

yeah,

some builders would love to have just a plan, an elevation and

a section, and I'll work it out

certain cer.

Okay.

So I. I think that is a good point because at a certain point that's how

I want the, the collaboration process.

That's where we need to start.

Hey, hey Matt.

Hey Hamish, how would you build?

What wall system are you gonna build?

Are you gonna use 35 mil vertical battens?

You're gonna use 90 mil?

Like, that's where that collaboration comes in and starts.

And then you can design.

So I think, yes, that builder wants the freedom, but that freedom

should be still in the design phase.

I agree.

The freedom should be in the collaborative stage.

Yeah.

During, during design.

So it can be documented

appropriately together.

Yep.

So, and if I'm, if I'm thinking about speed of estimation, you know, again,

we can estimate a set of drawings that's not completely resolved really quickly.

Mm-hmm.

When it's resolved, it takes us a lot longer 'cause we're

double checking everything by the time these documents hit site.

I want my team to be able to go, Hey, what's this wall type?

What's the battens?

Where's the cavity closer going?

Yeah.

And that wants to be di completely dialed in.

Mm-hmm.

That's a good set of documentation.

Mm-hmm.

But our DNA is through those drawings and our DNA is inserted

during pre-construction.

Yeah, agreed.

Because ultimately if it's a certified passive house project.

Exactly.

You are signing a document that says, I have built this Exactly per the drawings.

And let's go back to the first question you asked then would we put passive

house into a contract and to sign off on it, we need to make sure it all works.

Yeah.

So you, you'll check drawing.

We then risk, make sure you are happy to execute exactly what's shown, and if not,

you would ask the architect to amend it.

Yeah,

yeah, yeah, yeah.

And that I think is the right way.

Yeah.

Cool.

Okay.

So in your experience then, what level of precision genuinely matters on site?

Where do we.

As designers over specify a detail.

It doesn't meaningfully improve the outcome on site or add

value to the building process.

Uh, what I have,

putting blame in terms, are there details and drawings you just ignore.

So this isn't your fault as a design team, the, for some stupid fucking reason we

have the NCC and building todays make them copy diagrams that are in the n CCC to

have a whole page of like, oh, this is how you waterproof, this is how you do this.

This is a, a detail from the n ccc.

Why can't the builder be responsible for just looking up the NCC?

Do you know what I wanna see on drawings?

And this is probably on, on, in line with what you are saying.

Anything that's on that documentation, I want it to be 100% relevant to that job.

I don't wanna see like a standard detail.

Yeah.

Oh, this is just a standard detail, standard notes, standard note, whatever.

Like for me it needs like.

That just all gets watered down.

Like, I know my team on site just want to build the house.

Yeah.

Why is there masonry notes when there's not a brick in site?

Yeah, yeah, yeah.

Great.

And that's not your fault because the building surveys

make you put 'em in there.

Well, not always, no.

Sometimes there'll just be a carryover, like there's a template that

everyone uses and it just, I respect that you have to.

Yeah.

But over time, the thing is, like in those notes it says that like,

what a, a rising and going must be.

That's in the NCC.

Don't you know what, don't put, don't put information in there that's not relevant.

Don't like

quality is better than quantity.

Yeah, yeah, yeah.

Don't, don't just put stuff in there for the sake of putting stuff in there.

You know, the less information in those drawings is probably better.

I would love to see, when we go drawings, you know how

sometimes you get like the 3D.

Section of a rather than a 2D section of a say, a detail.

Why can't they start being more 3D?

And you know,

but they can, it's a, for the designers and architects is how much time do we

have to complete a set of documents?

Well, this is where I think the model is really important because you are

doing, you're drawing the model anyway.

Now, look, from an estimating point of view, I know for sanctum

homes, we are drawing them.

We, we are drawing the house.

That's part of our takeoff, if you will.

Yeah.

Okay.

Yeah.

Okay.

Okay.

So let's move on from documentation.

Mm-hmm.

No, now we're talking about going back to costing and, and, um, pricing projects.

Yeah.

Got a bit of a predicament in that no one actually ever prices

a home on square meter rates.

Okay.

That's just the wrong approach.

Yet everyone still uses them to talk about cost.

It's still happens, right?

As much as we hate it, it's happening.

If we wanna move away from square meter rates, what should we replace it with?

Linear meter rates, I dunno.

Um, uh, I just think

so what's a better way to help a client understand affordability

before anything is feasibility

study.

Okay.

I think, I think

Good answer

that at feasibility, at feasibility stage and we draw a very, very clear line

and wrap some very clear understanding around what feasibility is at that point.

Sure.

Throw, throw square meter ridge at it 'cause it's a really so

square meter rates.

Have a place,

have a place.

Feasibility.

Anywhere beyond that?

Absolutely not.

Do you guys track square meter rates of historical projects?

No.

Because they're all so different.

Mm-hmm.

Yeah.

I mean, we've got the data.

Yeah.

But we don't, we don't, we don't use it.

But what we do do though is we go, well, we know that pri

that project was that price.

Mm-hmm.

Uh, and oh, there's similar sizes we can go, Hey, you know what?

This is kind of similar to here, expect to be paying this or more.

'cause that project was 12 months ago and

the detail is important because some square meter rates will include

carports and garages and some won't.

Some will include the eve line and some won't.

Yep.

You know, there's, there's so many variables that the square

meter rate from one builder and is it from one house Will or is

person that should be talking square meter x is someone like price of

plan, but they don't talk, they break, they don't talk about, Hey,

the house is 7,000 a square meter.

The kitchen's 10,000, the bathrooms six.

The bedroom's four.

Yeah.

So they actually work out at a different way.

Yeah.

That's the way to talk about square meterage.

The problem is that data is.

Thousands of houses to be able to obtain.

It's

half a billion dollars worth of costing

data.

Yeah.

So I think feasibility, we talk about it and all you might say,

'cause again, is it double story is a single story sloping block.

We don't know.

But you could be like, what you want is like this ha house, Hamish

did, Hamish built this for this.

Assume it's gonna cost around there.

Plus inflation last year was 3.2%, maybe added a little bit more.

You are building in two years, add another three and a half

compounding for two years.

So therefore, realistically we're looking at this.

Mm-hmm.

And we need to understand with clients budget is not the build cost.

I think that's the main, I think that's a conversation that needs to

be had very early is what you, what

distinction between

those things.

Yeah.

Your budget is not what the build's gonna cost.

No.

That's what you want to spend.

Yeah.

Or can afford.

Yeah.

Yeah.

No, there al there always needs to be that, that clarity around, well

what's that number allowing for?

Yeah,

I, I say that we don't quote based on square meter rates.

However we do

use it,

use it as a tool to kind of give you a guide of where we

think the project's gonna land.

But you might be looking at floorboards, a square meter, Hey,

they're 120 a square meter supply.

Cool.

Oh, there's too many, you knows, far too many variables to try and yeah.

This is fun by the way.

I like this.

I like

this

one.

Yeah.

This more often.

So it's only warming up now, I reckon.

Sounds like you just

wait for the next

question.

These questions are boring.

Well, we sort of delved into this,

make 'em spicy.

This next question already, but I'm curious to hear your perspective on it.

'cause I didn't ask that before.

So I'm gonna back up to this.

On the site inspections carried out by architects and designers on projects.

Mm-hmm.

Um, so we've had two different responses, um, in, in recent times

during construction.

Yeah.

So we're coming out to inspect the building work now, one of the builders

couldn't have been more enthusiastic, turned to the clients and said, you

know what, this is a passive house.

It's important we get it right.

It's the first time I've done it.

I'm gonna cover half the architect's fees for these inspections.

The builder out of his own pocket, right?

That blew me off my chair, right?

Because it's not his house.

Right?

Did you

put your rates up?

But that's,

but then another builder said, well, I'm actually gonna charge the client

additional fees now for my additional time to sit down with that architect

and designer and walk them around the site and pause my work for a couple

of hours every fortnight or four weeks, or whatever it ends up being.

So maybe she shouldn't work with that door again.

What's your take on, how would you react and what do you see fair and reasonable?

Let's go back to your point before, and I think this sums up you when

you went on site once, we can't pick everything, we're gonna miss stuff.

That's the reality.

You went over something and it might be as simple as like, Hey, that

lighting spot doesn't look right.

We need a, that lighting, that light actually should be there.

I, I guarantee it's a lot cheaper for you to pick it up on early.

And I look at you guys coming on site as a free employee to

check over some quality work.

It's quality control as well.

It's just an extra step.

Well, it's free for you.

Yeah.

But, but doesn't, I know that's, I not, I don't say this.

It's, that's not my problem.

Like, I know, I think you're paying someone to do it.

Yeah.

I, I think, um, I mean, hat hats off to that other builder, like that's a,

I think, I actually feel that that's a really cheap investment on their learning.

Mm. So probably not a bad move from them.

Uh, we wouldn't charge extra when you, as the design team

are coming out once a month.

However, if it was an administered contract by an architect under Abic, then

there are additional, uh, administration fees for us for doing something like that.

Mm-hmm.

If we're just coming out on site and we're, 'cause we're doing

fortnightly site meetings anyway.

I've got kind of willow tomorrow.

Mm-hmm.

Just come along.

Come along.

I think

I might,

well, if you wanna go, that's fine.

Can

what time?

Uh, they'll be there at seven.

Yeah.

Maybe not.

Yeah.

But like that, that's, that's just like, I think if, if you are saying,

Hey, I wanna come at 3:00 PM and then I wanna come at two o'clock next week.

Yeah.

Now you, my rule is no, we have meetings at eight o'clock with our clients on

a fortnightly basis set at the start.

You jump in on that.

Yeah.

And we'll work, if you wanna come to every one of them, I might

say to, Hey, you guys, what?

Dave's work best for you and we can all grow on a Wednesday morning?

Or, or, or is there, I mean, I guess it's a question of, you know,

that you can have a conversation during, uh, pre-construction and

say, at what point do you see it valuable that you come out the site?

Oh, I think we should be there.

Um, site set out and onwards, like every, every other fortnight.

Like at all the milestones, every, every day.

Most importantly for us, because we believe in, in passive house and, and

the high performance outcomes of that, we wanna inspect all of those principles.

Thermal bridges.

Mm-hmm.

Um, insulation installation, because there's just not enough

oversight of that in our industry.

Uh, window installs, HRV, all that.

And you guys have done all this a million times, right?

Mm. So it's not, it's not directed necessarily.

That's not directed at us a problem with it.

I think the first time you do a passive house that way.

Yeah, a hundred percent.

You should, you should actually, as a builder want that help.

I think, I don't think site set out, because site set out can be quite

complex with multiple lines being run.

The time that we would send to run you through it would

be a whole day, probably more.

Yeah.

I think, I think I just look at it as it's a constant, like, it's like anything, if

you maintain something, you constantly go to the gym just on a regular basis.

You keep fear if you come and go and that doesn't work.

So I just say, come every second week, we'll fill you in with what you need to.

You don't need to know everything that we do on site.

No.

We'll come to you most like with a solution to a problem and, and,

or we can flag something early.

We're now, like for us, we're working through a sheet at the moment where,

so when we do an estimate at the start.

We have a list in Asana, TB, c items, um, unresolved items sort of thing.

So details that aren't resolved.

So from meeting one, I can like send, I need to know your tiles,

hurry up and make your decision.

Well, I think what we need to work out fin is how often we want to go

surfing at point Leo when Chorum starts, and then I think we'll just tailor

everything our site visits around that.

Nice wineries out there too.

So that's gonna be, yeah, most days pending the weather.

You're not building in winter, are you?

Uh, hopefully back end of this year.

So a lot of the high performance building playbook is imported.

Product is in everything in Australia.

Changing slowly, I'm sure with, with things, but, so where do

you think Australian projects, misapply, that oversees logic,

if you like, particularly around moisture, ventilation, solar control?

Are we, are we leaning too heavily into European data and systems

and methods and, and not doing it?

For an Australian climate, for example.

I,

I don't, I don't think so.

'cause building physics is building physics.

Mm-hmm.

And every, every time that you run something through PHPP, it's

using climate data from that area.

So I don't think, my opinion is, I don't think so.

Mm-hmm.

I think there's a misunderstanding of potential client saying, oh, well I

don't want to build a passive house.

You need triple glazed windows.

And we'll say, well, I've only ever needed triple glazed windows

on one or two passive houses.

And it hasn't been for all the windows, it's just been for some of them.

So I think there's a misunderstanding of some of the applications

of some of these materials.

But I think if you're building here or building in Queensland, or building

in Antarctic or a building in Canada, like, I think the, the idea is the same.

And I think the same products can be used.

I think the,

I don't think we're overcomplicating every

hundred percent, I reckon, I'm gonna be honest to you, as much

as we have some of the worst buildings in the world in Australia,

I think our best, best buildings are pretty much up there with the.

Whilst we're using materials from overseas, because let's be honest,

in Australia, we don't manufacture anything, so we have to import

and there comes a cost with that.

But I think what we're producing from a building perspective, the

best houses would compete with the most best performing houses

in say North America or Europe.

They just might have thicker walls.

Does that answer?

Yeah.

Does that answer your question?

Yeah, it, it does to a degree.

And I was kind of leaning towards our different climate and so what's happening

now in, in parts of Europe, obviously the climate is heating up and a lot

of those homes are designed purely for heat retention and now they don't have

any solar control and their homes are getting really hot and they're suffering.

So you're talking about we need more manual external shading, for example.

Well, so we don't design a passive house without it.

Right.

Like for us, that's the sixth passive house principle that

makes it design, shading.

Shading.

We have to have.

Operable shading systems and if budget gets stretched, okay, we

might change one or two to an eve, but eaves are, eaves are good.

Blinds are far superior.

Don't you think though, if you, if you're looking at the whole

system of passive house mm-hmm.

That external shading is an easy bolt on

it.

It can be.

Yes.

I took

it out

in

my house.

So, but what the point I'm trying to make is though the

other five principles aren't,

no.

So

they're ingrained into the building fabric.

Yeah.

So if, if these homes are starting to overheat, whack a blind on it.

Yeah.

Can

always retrofit a

blind.

That's what

I'm saying.

The modeling will tell you if you need the blind in the first instance.

Yeah.

But you are, you are saying existing buildings, which are now overheating.

Yeah.

Or, or under heating.

Is it 10% of the time it is.

That what they account for?

That's, that's a threshold.

But in Australia, you wouldn't do anything over 3%.

So it

just gets uncomfortable.

Can't you?

I, I don't know.

I'm gonna 'cause it

gets too hot.

Yeah.

And it does that.

I've only got two west windows at my house.

Good.

Yeah.

That's it.

There actually three.

Ones a bare bathroom.

But you do feel it heat up upstairs?

I get upstairs.

It's way, way more important for the, for them to have it.

I don't have it at mine, but I do it again.

Probably I'd, I'd put him in.

But I also go to a point is like enoughness.

Like what point do we keep?

Because if everyone does shading, what's the next thing everyone's gonna need?

And then what's the next thing

everyone's telling you?

I think it, I think we're shading.

I mean, unless it's on a second story.

I think there are other.

More, uh, aesthetic ways of shading your home and you bring landscaping into it.

So,

mm-hmm.

Yep.

Have we answered your question yet?

Yeah, I think you have.

We'll

just tick

that one

off.

How are we going

by the

way?

You're going really well, you guys.

Alright, thanks.

You've nearly passed the test.

Great.

Awesome.

Yay.

Um, so do you see there's a bit of contention in the industry here

about air tightness targets, okay?

Mm-hmm.

So, passive house requires 0.6 a CH air changes per hour.

A lot of people say you don't need to go that tight.

Who says this?

Oh, well, there are particular

naming

teams out names.

I'm not putting any names under the bus here today, but there are

people who would suggest that you don't need to go that airtight,

probably don't.

1.5 or two is fine.

Sure,

yeah.

You just get more control like the.

Well, I think

that, and so, uh,

so listen, what,

listen, how should designers and builders navigate that?

Can we talk, can we separate new, new homes to renovations here?

Uh, can I just say one thing before we dive in?

That if you listen to Jess's podcast with Wolfgang, uh, he,

they talk about air changes.

Mm-hmm.

And he basically said 100% of certified passive homes at 0.6 air changes or

lower do not have any mold problems.

Mm-hmm.

So I think that there is, and look, the risk is really low from three

below if you've got appropriate, um, ventilation systems as well.

But what

if it's

one

big hole?

If that, if that is verbatim what you've just said and, and I know we

can forget the exact wording, but if it's not 0.6 H well it's not a

passive house, so it doesn't count.

Okay.

I, I think, I think

we, do you know what I mean?

I, I know, I know what you

saying.

Was he, was he slipping something through there?

Yeah, yeah, yeah, yeah.

I think we need to separate, potentially, I think we need to

separate this in new homes and re.

New homes.

There is no excuse that why you shouldn't get a house under one air exchange period.

Well, I think the question is like, do we have to try and get 0.6?

Because there is, you know, if you actually look at the, I'm just speaking

in general terms here, so don't quote me on actual kind of results, but you

do have a bit of a diminishing returns at about three or two air changes.

No, it's, I think it's down, once you hit the about under one, it

really diminishes from that point.

Yeah.

But you start to see quite a significant drop after three air changes from

your energy consumption point of view.

Am I right in saying that?

Yeah, you, you do.

But at the end of the day, you guys, I think have, have both

said that you could just do an external wrap on a building mm-hmm.

And get 0.6 aach.

We

Yep.

Did we

do?

And you have done, I think, right?

Yeah.

So.

Yeah.

That isn't necessarily just about the product, that's also about the workmanship

Correct.

Execution.

This is where I, because if that's where I was about to get to, so

that's why I say new home you, if you don't get under one air exchange for

your external mar, unless, I'm gonna say take into complexity designs.

So some designs are quite complex.

Yep.

But let's just call it a double story gable, whatever.

Mm-hmm.

You haven't installed the product correctly.

That's not an air tightness problem.

You actually haven't installed the product the way it needs to be.

You haven't put the tape on correctly that that one air ex, that half an

air exchange could be coming from your roof, but you haven't put your, your

mento and tape that properly, which means that could be a water leak when

it condensates and run in, that's a bigger issue than the air tightness.

So I think that we use air tightness as a measure for how well I would

say we're keeping water outta the building when we hit that point,

rather than actually air infiltrating.

Mm-hmm.

Does that make sense?

Because if I know I'm at 0.6, I know that I haven't got water ingress

happening through my membrane.

If I'm at 1.5 on a new build, I go, well, where's my hole?

Hmm.

Interesting.

Mm.

Renovations a different per perspective.

So you would then advocate that, um, with a new build, um, we should be

able to deliver passive house air tightness just with an external map.

We

should on that.

Oh, I, so I'm, I'm gonna disagree with that.

I think you should be able to get around that one air change mark

pretty comfortably on in most designs.

Mm-hmm.

Whether you can get it into 0.6,

0.7, 0.6,

whatever it is.

But I think with an external membrane on a brand new home with a pretty easy form

mm-hmm.

Then you should be getting one air change.

Mm-hmm.

And just to be clear, we, we sort of pinpointed air tightness

as a particular topic on that and, and air tightness is, um.

An energy loss mitigation method.

Yeah.

It's not about vapor control or anything else.

Right.

So we're just talking about delivering

particular what kind of potentially, so let's, let's go in the argument

of someone that might say, no, we only need three, three air exchanges.

Alright.