So Sven, Passive House

claims to have 90 percent

reduction in energy.

What are your

thoughts on this?

I copped a lot of

flack because I was

trying to make it clear

that we are borrowing

marketing information

from the Passive House

Institute in Germany.

The Germans have done the

research and they've got

the data and they can prove

through their research

that they can see a 90

percent energy reduction

against a co built home.

Actually, I'm not even

certain that that's right.

Is it a code built home

or is it a standard

residential home?

I'm not sure.

The point I was trying to

make is that passive house

really shouldn't be focused

on energy reductions.

That's not the point

of passive house.

It's about health.

And so I was trying to

drive the message that

here in Australia, we can't

start touting 90 percent

energy reductions because

firstly, no one's done it.

The research to prove that

point and yet you can say

up to 90 percent really,

if you're going to say that

you should have the maths

to sort of back it up.

Now, the point that came

in the following slides

on that post was that we

should be talking about

the health benefits.

And I had this

conversation yesterday.

I don't know if you saw

our socials yesterday.

We handed over a passive

house plaque for our

Forest Hill Passive House.

And in chatting

to the client.

He made the point, he

drummed it home for

me then and there.

He said, this winter

we've just been through.

Says, I've had one

sniffle in my nose.

He says, in my previous

house, I would have had

a cold at least three

times through winter.

I notice it, and my

wife called it out

just a few days ago.

Hey, you haven't been sick.

Oh yeah, that's right.

We're now living

in a passive house.

Now there might be other

things, you know, the kids

are a bit older and there's

other things that are

changing in their world,

but largely their health

and comfort is far beyond

anything that they've

ever felt and lived in.

And so they weren't talking

about energy, they were

talking about health and

comfort, and that for

me was just beautiful.

But there's

So that 90 percent

probably isn't that far

off to be probably on it.

We're going to be

somewhere around that.

We could actually be more

because the code standard

house in Germany is going

to be probably a lot better

than the code standard

house or tent that we

build here in Australia.

And there is some data

that if you compare a six

star home to a nine star,

and we know that hers

isn't always the greatest,

they're getting data around

70 to 80 percent reduction.

And we all know that, like,

for example, with my house,

we did the Nathurst because

we had to, all right, so

obviously to get a building

permit in Victoria, and

we come in around 8.

1 stars, and I think

from memory, then I said

to them, can we change

the air tightness to 0.

6?

And that jumped

up to about 9.

1.

so maybe we are

around there.

Maybe that is the

thing, but we just don't

have the data on it.

And Passive House

saw that data, but

then you can't choose

And pick.

Hey Sven, for those who

don't know you, I mean,

obviously we have a great

relationship with you and

the team at Maxa, but can

you give the listeners

a bit of a background

to what you guys do?

And who you are,

Yeah, so we're a

practice that focuses

on high efficient

homes, particularly

passive house homes.

we work all over Australia

designing essentially

people's forever homes.

That's become our, our

sort of niche in a way.

It could be a

renovation project.

It could be a

large new home.

It could be very

small off grid, 64

square meter shack.

It doesn't really

matter to us as long as.

Everyone is trying to

chase the same rabbit

and that rabbit is a

more sustainable outcome

and we're good to go.

We love it.

So, we feel so blessed

with the projects

we get to work on.

When people trust us

with that particular

goal of, hey, this is

where we're gonna spend

the rest of our lives.

And can you guys

help us do that?

We get so excited by that.

. Now I've had the privilege

of going through the

process with your team.

and obviously I've

got, yeah, experience

in building.

I've built a couple

of homes in my life.

But what I loved about it

is actually the journey

that I went on because I

had this idea of how it

was going to be and what

we ended up with was,

completely different.

And I think that right

there really it's an

example of why you would

choose a building designer

or an architect to take

you on that design journey,

because they're thinking

about things differently

and asking these really

great questions about

how you live in the home.

And is that something

that you guys really take

ownership of when you're

doing that design process?

Yeah, absolutely.

The function of the

spaces is fundamental

to ensuring that there's

enough and not too much.

One of the hats we wear

at Maxar Design is we

oversee the Mullum Creek.

Housing estate in Dundalk.

And so we're often

reviewing the plans

of other designers

and architects working

for other families.

We don't see the brief.

We don't get told

what they've been

asked for, but.

You see living rooms

that are, 14 metres

long and 8 metres wide.

you look at it, you go,

well, how many people

are they accommodating?

I don't understand

why that needs to

be as big as it is.

I don't have

the background.

I don't

They've got to play

cricket inside.

I

yeah, look, maybe

they've got four

table tennis tables I

need to accommodate.

I mean, who knows?

But, what is enough?

And I know Amelia Lee

talks about this on her

podcast, but I think we

need to be having more of

those conversations about

getting the scale right

and the function right.

It's very easy to make

a big open plan living,

dining, kitchen space, but

does that make the living

room functional or does it

become very noisy because

there's clutter in the

kitchen and you can't hear

what's going on the TV so

you turn the TV up louder

because there's noise in

the background and the

background noise has to

get louder so it can hear

what it's doing and then

suddenly all these spaces

are fighting against each

other, maybe living room

should be just a little

bit separated out, still

connected visually, you

know, a bit of passive

surveillance for the

young kids or whatever.

But, . Big gargantuan rooms

are gone it's just about

creating a space that works

really well and functions

thermally, acoustically,

and for the family in it.

And everyone's complaining

about building costs at

the moment, and rightly

so to I totally agree.

But as we keep building

these homes bigger and

bigger, it's not like

they get cheaper and

cheaper making 'em bigger.

And, you can't have

your cake and eat it

too, sort of thing.

'cause space costs money.

And that's one of the

things I find and what the

houses designed to work

essentially and function,

are the ones that get

on site and get built.

now Can we just sort of

talk about the difference

between a building designer

and architect for a second?

Because I think there's

a lot of confusion here.

And sometimes building

designers can be put

into a negative category.

I personally feel that

a very good building

designer is as good as

a very good architect.

There's good and bad

in everything like

there's good builders,

bad builders, good

plumbers, bad plumbers.

I just want to touch on

that a little bit because I

know it's something you've

spoken about in the past.

Yeah, I think you're

absolutely right.

At the end of the day, it

comes down to the skills.

Of the individual just like

anything like art, you'll

walk into a gallery and

you'll see three pieces

you love and there'll be

six that you don't like,

training is different.

The pathways are different,

but at the end of the

day, we can deliver

exactly the same services.

How's the training

different?

Isn't it essentially just

learning to design a house?

uh, the training for

an architect and I

haven't been through it.

So I'm only speaking

from the architects I've

employed and what I've

reviewed and learned.

But it's far more intense.

There's a lot more focus

on materials and design

process, creativity.

They really do get

pushed harder on

those sorts of angles.

It's more time in

training in university,

whereas building design

is a shorter course.

Perhaps a little more

practical focus and

a bit of dabbling in,

in various angles.

You know, some people will

do that course and go off

and become a draftsperson

for precast concrete panels

or steel shop drawings, or

they might do electrical

plans or whatever that is.

Right?

So you sort of go off

on different angles.

precast concrete

industry for eight years.

And I learned to shop

detail and so that taught

me a lot, you know, which

carries through to this day

where I sort of have this

thing I can't shake where

I need to get into the nuts

and bolts and work it out

and make sure it's actually

going to go together, it's

very practical perhaps

and sometimes I burn a

lot of time doing it.

But it's for me it's

just something that's

ingrained in me from eight

years in the industrial

precast concrete world.

I think that experience,

diving into the details,

probably really served

you well Now that you are,

have become an expert at

designing passive houses,

because we all know that

level of detail on the

documentation is super

important when we're

actually striving to

get certified projects

Absolutely.

Yeah.

Particularly when it comes

to how you're going to put

a connection together to

avoid a thermal breach,

knowing how a builder

wants to assemble things

and what order of process

they'll work and all

builders do it differently.

This is what makes it

difficult is having a

builder on the team.

Early in the process

really helps because you

can talk to that builder

about their preferences

and methods and they'll all

want to do it different.

So every time we do a set

of documents, it changes.

We don't have standard

details in our practice.

There's a lot of practices

out there will have a

library of standard details

and they'll just drag and

drop them onto a set of

plans and they'll bulk out

their plans really quickly.

And they'll end up with

five pages of details,

but how accurate and

relevant they are is

the problem I've got.

And so I've said from

day one, you know, for 20

years we've been going, we

will not have a standard

detail because they were

my nemesis as a detailer.

You just get this page of

standard details and only,

two of them were actually

relevant to the project

you were working on.

And even then,

mathematically, they didn't

work with the project.

Thank you.

I couldn't agree more.

as a, As a builder.

you know, if you think

about a building site,

it's incredibly dynamic

and you're making hundreds

of decisions every hour.

And if you're flicking

through a set of documents

on your iPad or in a

hard copy, and you go

to the details page and

you're trying to find

something, and then

there's 12 irrelevant

details on there, that's

incredibly frustrating.

So having details that are

actually relevant to the

project is so valuable.

Is there any excuse for

any building, designer or

architect not to design

for health, comfort,

energy efficient,

and sustainability?

Is there any excuse,

in my camp, but I can

see that if a client is

demanding otherwise, then

the ability designer is

purely going to apply

the minimum standards

from the regulations

to make it Approvable

But what client goes,

Oh, I don't want a

comfortable house.

Like, let's be serious.

The one that says I can't

afford to do anything more

than the minimum standard.

Yeah, but like the thing

is like, it's so easy

as a designer, just

orientate your building

correctly and then you're

probably already without

adding any extra cost.

Like it is the basics.

I know.

I know.

And so you think about it

like, you know, we went

through this in the 70s.

We had passive solar

design kickoff.

I was born in 75, right?

I'm speaking from what

I've read and learned

from other people, etc.

So, we had homes that

were very leaky, but

were passive solar.

And then they got tighter.

so we had homes that had

indoor air quality that

was five times worse than

outdoor and then we had

air conditioners come

around and, hey, we can

build bigger homes and

just heat and cool them.

Electricity is cheap, off

we go and now we've sort

of come full circle and

we're into this world of

building physics and homes

that work much better,

but now we've learned and

we know better and we put

ventilation systems in and

do all these things, but

the codes aren't there yet.

Passive house is but

the codes aren't.

Claire Parry said it

herself, you know, like the

minimum you need to do for

a home that is condensation

free is a passive house.

The codes won't

deliver you that.

Codes won't deliver

you jack shit, really.

they completely

contradict themselves.

Like I was yesterday

talking about to a

building surveyor.

Yeah.

Around polished concrete,

in a toilet, you can't

have polished concrete

in a water closet, but

you can have it in your

kitchen because they

worry about the water,

which makes no sense.

I would arguably say

there's more water

coming out from your

tap in your kitchen

than out of a toilet.

Different if it's a bidet,

completely different, but

like They're essentially.

I feel at the moment,

they're a bunch of

big industry companies

putting stuff together on

a piece of paper to get

their product relevant.

That's how I feel they are.

But I think we need to

actually stop talking

about passive house

and energy efficiency

and sustainability

and just talk about

building science.

Because if we talk

about building science,

all of that comes.

The rest of it comes,

the energy efficiency

is a byproduct of that.

If we just build basically

off the fact of energy

efficiency, you don't

know what outcome

you're going to get.

You're probably going

to fuck your building

up more, potentially.

Especially with a retrofit,

they're the most dangerous.

We just whack some

insulation in the walls

and plaster and off we go.

think the message of

marketing needs to

change and not many

people understand

how to talk about it.

And I feel that this is

why so many architects

and builders fail to

get this message across

to clients because they

sit there talking about

the data and under the

kilowatt hours and the

U value on your windows.

Like they don't give

a shit about that.

They just want to

know they've got a

healthy, comfortable

house that's going to

be last and be durable

and talk about that.

And that's why one of

the things we do when we

consult on passive house to

others, which is something

that we've only been doing

for the last 12 months.

We produce a client

facing report.

And then we produce a

technical report for the

architect and engineer.

And the client facing

report focuses on the

health and comfort of

the home and a bit of

the energy efficiency.

And that's what

they care about.

They don't care

if they need R3.

5 bats and the

lambda value of 0.

4.

They care about how

hot and cold is my

room going to be?

Can I sleep well?

How much air

conditioning do I need

to run, et cetera,

And I think in a world

where at the moment

everyone's so worried

about exercising, keeping

fit and healthy, like what

numbers and preservatives

in the food that you

buy at the supermarket

and got to eat a healthy

diet and not vaping.

We're banning all these

things, but that product

that we are living in

90 percent of the time.

Is completely ignored

that actually has probably

just as much impact on

your health as nearly

anything else that we're

going to do in our lives.

data is there though,

like There's a study

that's been done that

shows that 50 percent of

childhood asthma cases are

linked directly to mold

and they think depression

cases can be just as high

because of the mold and

the issue with indoor

air quality in a house.

Like, these are studies

that have been done.

Already in

Australia, like what?

Why aren't they like

being talked about more?

It's like they get ignored

and I get so frustrated

about this because it's

just, it's like we pick

and choose what works

for us and what doesn't

when it suits us.

Yeah.

And I think you've

got to be careful with

statistics too, right?

Because, and I'm not

saying this to be negative.

I'm saying this to, for

people to be cautious

because ultimately when

people do research and

gather statistics and data

and come out with claims

of a 70 percent reduction

in this or a 20 percent

improvement in that, it's

based on the numbers of the

research they've

done and that

I'm only talking peer

reviewed journals here.

I'm talking proper

published in.

scientific journals.

I'm not talking about the

study that my fish and

electric home did between

their viewers or whatever.

Like I'm literally talking

about, proper reviewed

journal articles that

are done by experts , in

the field and that have

the ticker approval.

Not a white paper,

nothing like that.

Like proper five, six

year studies that someone

has now a PhD in it.

Not some woo woo

crap that suits the

argument or funded by

the steel industry.

that's what I'm

talking about.

Like proper time spent

on the information.

, so, max Design's

been around for

the last 20 years.

at what point on

that timeline, did

Passive House become,

a big focus for you?

Passive House and

Healthy Buildings become

a big focus for you?

the first I heard of

it was probably back in

2012 ish maybe a client

came and asked for it.

An Irish lady actually.

and I remember looking at

it and I was like, No,

you don't need to do that.

Like a seven star home

back then would have

been a great result.

And then 2015, we put

our first designer

through the course.

And then I did it, I

think, in 2016, the course.

you can't unlearn

this stuff.

I remember a slide from

one of the conferences

once you've seen a, thermal

bridge, suddenly you

just see them everywhere.

You're driving along

down the street and you

see concrete balconies

projecting out from

an apartment building.

suddenly it's just

turns on in your head

and you can't shake it.

So that's probably where

it really kicked off.

we started throwing

ourselves in, we talked to

all of our clients about it

and things kicked in pretty

hard, pretty quickly.

How do you talk

about it to clients?

How do you bring the

conver like, because

they're coming to you,

like, you're, you're in a

position now where you've,

everyone understands

that when they come to

you, it's pretty much

what they get, all right?

How do you talk about it

to the client that goes,

what are you talking about?

Never heard of that word.

How was it back then

more to the point?

Because I feel it's

probably easier, it's

an easier sell now

because there's more

education, but rewind five

and to be honest, yeah,

now we've got like,

everyone that knocks

on our door basically

is coming to us for it.

Right?

So, as far as saying nearly

everything we're working

on is passive house, but

back then when we were

making the transition.

It was really about the

building quality and I

was talking to clients

about, yes, you'll

pay more for this.

However, what you're

building is going to

stand the test of time

because we are building

a structure that is

protected with membranes

and you have a home that's

ventilated and super

healthy and comfortable.

You'll have this

structure that is.

retaining its

integrity forever.

You know, That timber won't

rot, it won't degrade.

And so the structure

will be there.

You can change your

claddings, you can change

your kitchen and do

whatever you need to do.

But ultimately, from a

sustainability perspective,

we're not smashing down

homes every 20 years and

putting up another one.

So these buildings

were designed to last.

sustainability.

perspective, that

floated my butt.

I got excited by that.

And I think when you

talk to clients and

you're excited and you're

up and about clients

sort of go, wow this

really means something.

I know everyone talks

about sustainability and

how are we sustainable

doing this, but really,

if you don't follow these

principles, the most

unsustainable thing you can

do is build a house twice.

You can put all the

recycled timber in and

choose the correct products

there internally that

make it look beautiful and

pretty, but if it doesn't

last, it ain't matter.

Yeah, that's it.

And I mean, as, as I said

this before, many years

ago, and I'm sure someone

else said it before me,

but I mean, the most

sustainable house you build

is the one you don't build.

We are all fighting

hard to make them as

environmentally friendly

as we can, but they

passive houses, I think

some of the kickbacks

sometimes people say

in the argument against

it is, oh, they're not

environmentally friendly

with material choices.

that's not taken into

account in the PHPP

side of things, which

I understand, but the

problem is, the flip side,

the argument that people

that are doing this are

already generally on the

material choices anyway.

So yeah, you could go buy,

build on with, concrete

and steel frames and

get a passive house, but

is it cost effective?

And not.

from a sustainability

perspective, I think

Passive house needs to move

in that direction somehow.

And carbon accounting

is a good thing, but

you know, we can still

use petrochemical based

insulation products and

plastic based membranes.

And, you know, there's

lots of challenges we

still need to overcome.

not that bad if it's

used in the right reason,

for the right reasons.

Like, I think we

need, we just need to

consume less of it.

And just be smarter

with our choices.

Like we can't remove

plastic from it,

like at all in life.

I think about all the

surgery tools that

are set, like plastic,

we can't change them.

and having a little

bit of it is okay.

Not building a hot

plastic building, but I

think sometimes we also

overcomplicate it and

that if the worst part

of my building is that

we're putting a bit of

petrochemical foam into

the slab to keep it warm,

it's going to last forever.

Is that a problem?

the

question I would ask

is, Can you do it in

another way that is more

environmentally sound?

the, yeah, not

at the moment.

There will be, and I

sometimes take the boomer

approach, like there was

something else that will

come out, or there's a

way that we'll be able

to recycle in the future.

Currently, there's

probably not.

And there's smarter

brains out there than

the three of us combined

to work that out.

Well, there's a future

challenge for Sven.

So Sven's , been

engaged to design our

house at some point

in the next few years.

And I guess the challenge

for both of us is to build

a passive house that's

also thinking about all

the things that we put

in it and try and remove

some of those plastics.

I'd also argue on the

flip side of that,

what is perfect?

I don't think

there's a perfect

approach to anything.

I think what's the

better approach?

What's the more long

term sustainable approach?

Yes, it's plastic.

Yes, it's petrochemicals.

But if you would build the

same house without those

things, but the house is

also consuming from an

operational point of view,

so much more carbon or so

much more energy to heat

and cool it, what's better?

The house that is really

shit, but can be recycled

at the end of life, or the

house that's left standing

for a hundred years has

a bit of petrochemicals

and plastic in it, but

has a allegedly 90 percent

less energy consumption

than the other house.

I mean, in my mind, from

a practical point of view,

that's the better option.

That's the more

sustainable option.

if it's a one or the

other, then sure.

But What else is there?

What other

options are there?

What can we find?

There must be another way.

There must be a better

way, let's do better.

Let's do better.

And I constantly,

I don't settle.

I'm not very good at that.

So, yeah, I just, I would

like to think that there's

a way we can do it with

natural materials, and I

reckon there is, I just

haven't done it yet.

And I haven't seen anyone

else do it completely.

essentially comes

down to the client.

That's like a bit of an

open ended bank account.

And you get to trial

some stuff because

that's what unfortunate

people like us or myself.

I can't afford to like

try some things that

we don't know, and

expensive material.

We were very lucky

with that, Matt, on

that project we did in

Brisbane, the Canal House

project, we used, uh,

earth friendly concrete,

that was absolute

trial and error.

And we know it had been

used for precast before

but, and we knew they

were pouring in large

volumes for commercial

projects, but for a small

residential project,

they were very much

can you, tell us a bit

more about it, Sven?

I'm really interested

about this concrete.

Yeah, so it has no cement.

It's 90 percent carbon

emission reduction

compared to normal.

it's basically a

geopolymer product.

Now the science of how it

works, beyond me, right?

it looks and feels

just like concrete.

and performs similarly,

perhaps has some more uh,

benefits and it's good in

salt water environments

and in those sorts of

marine environments.

So it has lots of

benefits to it.

And I've lost a

lot of the detail.

We looked at this, we

specified this back

in 2020, I think.

So this is when I did a lot

of research back then, but

it was a real challenge.

And we, we set the goal of

doing all of the concrete

on the entire house.

footings, everything out

of this particular product.

and the client paid

overs to do it.

Like he was absolutely

a hundred percent

in and credit goes

to him for being

willing to pay for it.

And the builder as

well, willing to sort

of push boundaries

and make it happen.

So it's very easy for us to

do research and then just

write it on the drawings.

That is what we're using

to practically execute it

as a whole other thing.

so they say up to 70

percent reduction in

carbon, based off the

numbers that they're

using slag fly ash and

all these other things

to remove the Portland

cement, the recycled water

content, power, whatever

to generate the mix.

, I know there's a lot of

different methods out there

where they're looking at

using like old car tires

and coffee granules and

all these other things

to like microplastics.

That's a big one.

I think in the future,

you could maybe use

microplastics, but I'd

love to know the difference

between the two, because

the other thing that we

need to be careful with

this, and I called this

out a little bit, is the

fact that buying tree to

offset the carbon of the

concrete is just we're

all buying the same tree.

At the end of the day,

so it comes down to

what percentages in the

product itself, not all

these extras you can

buy to make it sound

pretty and beautiful.

And I think the product

that you guys have used

is probably very similar.

I'd say to what we've

used at our own project.

because it does work a

little bit differently,

takes a little bit longer

to dry and a little

bit longer to cure.

from a pumping point of

view, it's a bit stickier.

Yeah.

the feedback has been,

but other than that,

that no difference.

cementitious

product, right?

What you're using.

Whereas the

Wagner ZFC is not.

so, so I thought they, I

thought you still need at

the moment, they haven't

been able to figure

out a way to remove the

Portland cement completely.

They still need binders to

actually make this work.

Yeah, and like I said,

I've, forgotten all the

statistics and data.

And because it's in

Brisbane and we only got

to use it that once for

that project I've sort of

let it go, you know, I've

moved on to other stuff

and what we can do here

in Melbourne, perhaps.

But,

if anyone wants to know

more about the Wholesome

Eco Pak stuff, uh, I

did a webinar with them

probably two years ago

for Sustainable Bills

Alliance, so that sits

on the SBA website, so

it's probably worthwhile

having a look, but I do

believe, Matty, that the

higher percentage carbon

reduction is using offsets.

It's

not about

70%.

Yeah, no, it goes to a

certain percentage, and

then to go to 100%, you've

got to then purchase it.

Does that make sense?

I only went to what

the product can offer

because at the end of the

day, the reason we talk

about this, I think it's

good to educate people

who are listening, that

Concrete's one of the

biggest contributors

to global warming.

When it's, I think

it's 8 percent of all

greenhouse gas emissions

come directly from

producing Portland cement.

So, if we can make a

big hit on that, that's

like, we can make a huge

change to our carbon

emissions in a project.

I just want to say just

to close out the whole

concrete thing, because

I mean, at the end of

the day, concrete is a

fucking amazing product.

, when you partner with

steel good tensile and

good compressive strength,

such a great product.

And again, it's all about

this balancing that we talk

about, you know, if that

building with that concrete

slabs are going to be

there for a hundred years,

yes, we need to reduce the

amount of emissions that

we're doing by producing

concrete, but it is a great

product to build out of

because it's so durable.

Anyway, it's a whole

other topic, but yeah,

I want to know more

about this Wagner stuff.

So if anyone's listening

that knows more or

Wagner's, if you want

to come on, shout out,

I'd love to

unpack this more.