Interviews with the leaders, practitioners, and change-makers in the global Passive House movement. A production of Passive House Accelerator.
00:00-00:04
- People don't know to ask the question.
00:04-00:07
And if you don't know to ask the question, you don't ask it.
00:07-00:12
People didn't know they could have a house that was sealed from bugs and dust.
00:12-00:16
They didn't know that filtered fresh air 24/7 existed in a home.
00:16-00:20
- There's to know how to make fantastic buildings.
00:20-00:22
And then there is to cause that to happen.
00:22-00:26
And the Passive House community is causing it to happen.
00:26-00:28
It's starting with the knowing and causing it to happen.
00:28-01:00
- Hello and welcome to the Reimagine Edit, a special series of the Passive House podcast that shares curated insights from our experts and residents at the Reimagine Buildings Collective, our membership community that brings together building professionals ready to tackle climate change so that we can create the healthiest, most sustainable buildings, deliver them cost effectively, and thrive in the process.
01:00-01:02
Today is March 24th, 2025.
01:02-01:10
And in this episode, we'll hear from Ryan Abendroth, Michael Ingui, Kristof Irwin, and Tom Bassett-Dilley.
01:10-01:15
I'm Zack Semke, director of Passive House Accelerator and host of the Reimagine Buildings Collective.
01:15-01:18
And I am delighted that you've joined us.
01:18-01:20
Let's dive right in, starting with Ryan Abendroth.
01:20-01:24
Ryan is co-founder of BuildZero Consulting.
01:24-01:34
He's an experienced certified Passive House Consultant, the former certification manager at Phius, a member of the Phius Technical Committee, and a trainer for the Phius CPHC program.
01:34-01:42
In this first clip, he responds to a question about what sort of background is required to get into Passive House Consulting.
01:42-01:49
- Do you have any examples of people that you know who've working as Passive House Consultants, who don't have all that extra background?
01:49-01:51
Anybody might be good to talk to?
01:51-02:02
- I think there's quite a few actually, who started in one thing and transitioned to something else, or at least don't have the formal education.
02:02-02:10
Maybe they were builders of some sort, or there's a couple other rarer ones.
02:10-02:18
There is someone that has been in the Passive House community for a really long time, and you would think, yeah, they are an expert when you talk to them.
02:18-02:25
And their college degree is in fine arts dance, and they were a dancer.
02:25-02:29
And so, you know, I think it's definitely possible.
02:29-02:32
It's a little bit trickier to break in, I would say.
02:32-02:36
That's the only trick is like, how do you get work?
02:36-02:48
Whereas if you're already doing architecture work or building work, or there's like kind of maybe some built in clientele or networking in the industry that will come in very handy.
02:48-02:53
But I don't think the background really plays too much of a role in that.
02:53-03:00
- I know that Passive House expert with a dance background, and they're brilliant and deeply technical.
03:00-03:04
So some proof positive there that it's not about your college degree.
03:05-03:11
Next up, we have Michael Ingui and insights from his AMA about how to sell Passive House.
03:11-03:23
Michael is founder of Passive House Accelerator, president of Ingui Architecture, co-founder of Source 2050, and one of our most gifted communicators about Passive House and its benefits.
03:23-03:26
Here, he starts a bit tongue in cheek.
03:26-03:29
- But let's get into how to sell Passive House.
03:29-03:34
What I usually do is I usually tell the clients exactly just how I learned it.
03:34-03:40
I tell them about either the Passive House planning package and what that is, or a WUFI and what that is.
03:40-03:42
I really get into it and how we use Excel and how we track it.
03:42-03:47
And I very often will talk to them about the contractor training and how they get into it.
03:47-03:53
And then sometimes what I'll do is I'll really talk to them about just the energy benefits and how much better it is for the environment.
03:53-04:06
And what I'll do is I'll talk to them about just the KPIs of just how you're getting into it, or even just what a blower door test and just how many air changes this house has versus another house and how we get to it.
04:06-04:11
Sometimes I'll talk about just the insulation and some of the increments into it or some of the technical...
04:11-04:12
No, I don't.
04:12-04:14
I don't talk about any of that crap.
04:14-04:14
Nobody cares.
04:14-04:15
Absolutely.
04:15-04:21
Even the ones who come to me wanting Passive House want to hear about any of that.
04:21-04:23
They just don't care.
04:23-04:25
They want a really wonderful, beautiful home.
04:25-04:28
They want to know that they're working with someone who knows how to get them there.
04:28-04:34
And I just don't focus on it because it is the easiest way for me to lose the project.
04:34-04:35
Forget about Passive House.
04:35-04:39
They will either have fired me at some point or they just won't hire me.
04:39-04:41
I mean, very often I'm up against four or five architects.
04:41-04:47
And I can tell you recently I've gotten projects that others haven't because we do Passive House.
04:47-04:48
And it's not because they do Passive House.
04:48-04:50
Again, they don't care about it.
04:50-04:51
They just don't.
04:51-04:53
They do, but they don't.
04:53-04:55
What they do care about are the amenities.
04:55-04:57
And that's what I focus on.
04:57-05:02
So in this house, this developer was interested in creating the best house they could.
05:02-05:08
And so they were hooked instantly and super excited about it and very, very involved at the end of the day.
05:08-05:18
But what I did was I walked through with them and I said, listen, if you want a house that is sealed from most bugs and dust and outside allergens, we probably could seal it like a Passive House.
05:18-05:29
And if you want a house where you really don't hear too much street noise and it's super safe because it's triple paned glass that's laminated, we could do Passive House windows.
05:29-05:36
And because I've got the sealed house, I can do a filtered fresh air system that we use in Passive Houses.
05:36-05:39
And they're like, well, what's a Passive House?
05:39-05:40
Now they're excited.
05:40-05:44
You know, I had them at filtered fresh air and sealed from bugs and dust.
05:44-05:48
People don't know to ask the question.
05:48-05:51
And if you don't know to ask the question, you don't ask it.
05:51-05:56
People didn't know they could have a house that was sealed from bugs and dust.
05:56-06:00
They didn't know that filtered fresh air 24-7 existed in a home.
06:00-06:11
They don't understand that when I turn my kitchen exhaust fan on at 500 or 1,000 cubic feet per minute, they never thought about what that meant.
06:11-06:19
That every time they do that in their current house, that the fresh air is coming from crevices and cracks that they had never put their fingers near.
06:20-06:24
They just, they don't know this, but when they do, they cannot turn it off.
06:24-06:25
They can't turn it off.
06:25-06:26
Like, they want it.
06:26-06:27
They don't care what it is.
06:27-06:36
And what's important about that is the thing that does cost more in time and money in a Passive House is the air sealing.
06:36-06:38
I wouldn't have done that in another house.
06:38-06:41
But if people know they could do it, they want it more than they want anything.
06:41-06:45
Because nobody wants the house that's got bugs and dust.
06:45-06:46
Like, nobody.
06:46-06:46
Nobody.
06:46-06:52
And then from there, we can talk about the fact that I really don't need to heat the houses that much in the winter.
06:52-06:56
Then you could talk about the fact that your belly need heat, which means I don't really have dry winters.
06:57-07:01
Or we can talk about the fact that the cooling is significantly reduced, especially if I do the shading right.
07:01-07:09
Or the fact that if I'm getting my filtered fresh air 24-7, I get filtered fresh air and I don't have the allergens in the house and they're healthier.
07:09-07:14
I can get into all that afterwards, but I got to be super careful about how I get into it.
07:14-07:17
It's got to be a slow roll.
07:17-07:19
And you just have to focus on the amenities.
07:19-07:27
And when you described to the clients the things they didn't know they can have and the other architects who walk through, don't.
07:27-07:30
You get the job.
07:30-07:32
I mean, it's just amazing.
07:32-07:35
And then they're talking about it in their initial design meeting.
07:35-07:37
And then they're Googling it before you even meet with them.
07:37-07:40
And then they're totally into it because they just didn't know it existed.
07:40-07:42
You know, Passive House is not the best name.
07:42-07:44
Neither is Net Zero, by the way.
07:44-07:45
Or Low Carbon.
07:45-07:47
Or any of the stuff we're going to talk about.
07:47-07:50
It's just none of this stuff is very descriptive of what you can get.
07:50-07:52
But everybody wants a healthier home.
07:52-07:54
Everybody knows what filtered fresh air is now.
07:54-07:56
So that's how we've been able to do it.
07:56-08:08
And I can tell you, I have made the mistake recently, still, of getting caught up in how we do it too much in that initial meeting, in that initial conversation.
08:08-08:11
And I can tell you, it can go south so fast.
08:11-08:12
Just so fast.
08:12-08:16
But what about when they do ask what Passive House is?
08:17-08:22
Yeah, eventually, like you said, they'll say, well, so what is Passive House?
08:22-08:23
What is this thing that you're referencing?
08:23-08:35
How do you answer that question without doing exactly what you've been saying not to do, which is getting too far into the weeds?
08:35-08:37
Yeah, it's a great question.
08:37-08:40
And it does let you get into the weeds a little bit.
08:40-08:51
So the way I describe it is Passive House is a certification that started years and years ago that they've been building in Europe for longer than they've been building in the U.S.
08:51-09:00
because the gas prices were higher than they are here, where we're taking just industry knowledge and just building better homes.
09:00-09:07
What we're doing is we're using Passive House principles to do things like break thermal bridges.
09:08-09:12
And, you know, I'll do things like hold the coffee cup I'm holding right now that is super hot, by the way.
09:12-09:14
And the fact that I'm burning my hands right now.
09:14-09:19
But if I simply put this piece of paper on, which I'm very happy to do, I've just broken that thermal.
09:19-09:20
I've got a thermal break.
09:20-09:30
And we're learning little things like that, that when you pile them up, all of a sudden I get a house that doesn't need a lot of heat.
09:30-09:31
All of a sudden it's sealed.
09:31-09:33
And we've learned so much.
09:33-09:39
But it's a certification process and a systematic approach that allows us to create better buildings.
09:39-09:46
Now, I definitely do have clients who ask me beyond that, including the client where I'm sitting in.
09:46-09:48
Well, yeah, but like, how do you do it?
09:48-09:50
If that's the case, go for it.
09:50-09:52
You know, now they really want to know.
09:52-10:03
And so for me, from that standpoint, you may want to think about it and even practice it a little bit because you still can't meander.
10:03-10:07
And there you have it, folks, straight from one of our best.
10:07-10:15
In this follow-up question, Michael shares his approach to how to distinguish passive house from passive solar.
10:15-10:23
Do you have a canned response for someone who thinks they know what passive house is, but they're actually thinking about passive solar?
10:23-10:25
Yes.
10:25-10:25
Oh, yeah.
10:25-10:27
Oh, I get made fun of all the time.
10:27-10:34
So for the record, my partner, who's 80, has done some passive solar work and makes fun of the passive house name altogether, by the way.
10:34-10:36
I mean, it's not truly passive.
10:36-10:38
And so it's not the best name in the universe.
10:38-10:47
But the passive solar community, the way I describe it, and I've been helped by him a lot, by the way, paved the way for this.
10:48-10:54
I mean, we learned so much through the passive solar community of what to do and what not to do.
10:54-10:58
And then especially the overheating part.
10:58-11:02
I think the passive solar community wasn't so different for me at the beginning.
11:02-11:10
I got so excited about the fact that I don't need to heat these houses in the winter that everyone cared about the shading on the south side.
11:10-11:14
And then that's what having a passive house consultant hit you over the head is really helpful for.
11:14-11:17
We don't even design these houses for heat anymore.
11:17-11:46
But yeah, I think the difference between the passive solar, just coming back into a canned response, is the difference between passive solar and passive house is I think passive house is a natural progression of the passive solar movement where there are so many buildings worldwide already completed under the passive house measures, both in the US and in Europe, that we've now learned so many things that we can do that can now be implemented on other houses.
11:46-11:49
And we've learned that they need mechanical units.
11:49-11:54
They need things that allow fresh air in when I don't have the doors and windows open and so forth.
11:54-12:00
So yeah, I feel like it's a good response because a lot of people, if they're asking the question, they know enough to know.
12:00-12:06
So I think answering it in a way where you're providing some kudos to a movement that still works really well.
12:07-12:15
One of our passive solar houses that my partner did recently sold and the person called us because they wanted to do some work in the house.
12:16-12:19
And I can tell you, it still works really well.
12:19-12:26
Like the dark tile inside one of the walls where they're gaining some of that solar gain, it's still working.
12:26-12:33
And what's cool about some of the things that we've learned from them, it's not working because the mechanical unit is still working.
12:33-12:35
It's working because it didn't need mechanical units.
12:35-12:38
It's working because they thought about where the sun would hit and where it wouldn't.
12:39-12:48
And I think a lot of that goes into the passive house planning package or the WIFI or whatever modeling software you're using, where you can start to really use the benefits of what they've learned there.
12:48-12:49
Cool.
12:49-12:50
Yeah.
12:50-13:08
Describing it as a progression feels like a really good way to not tell them they're wrong and not contradict them, but to tell them that, okay, it's coming from that, but it's actually a certification process that has moved further along.
13:09-13:18
Yeah, not like that, but if they really did know a lot about the movement, they would know about the negative articles written about the passive solar movement as well as the positive ones.
13:18-13:30
So there's a lot of passive solar houses that work very similar to the way I got excited about not having to heat houses and not caring how it's shaded to the south side windows, not realizing, oh, you know what?
13:30-13:31
Honestly, it's getting hotter and hotter.
13:31-13:33
Even in New York, I'd better care.
13:33-13:43
So just coming back into that progression, having your passive house consultant make sure you care and having the model fail because you didn't think about it.
13:43-13:44
That's the progression.
13:44-13:46
And it de-risks it.
13:46-13:51
Again, I can't get that excited about it because I'm getting hit over there with a model that shows it doesn't work.
13:52-13:57
When it comes to selling passive house, Michael says to start with the amenities that clients didn't even know existed.
13:57-14:00
And I love just reading people and seeing how it's going.
14:00-14:05
And I get a lot of unsolicited feedback from my clients as well, which I also like.
14:05-14:10
I tend to get a lot of unsolicited feedback from everybody, but I like it.
14:10-14:11
It's okay most days.
14:11-14:16
And I can tell you, starting with the things they didn't know exist is important.
14:17-14:26
Starting with the fact that if you want a house that's sealed from most bugs, dust, pollen, outside allergens, we can seal it like a passive house.
14:26-14:37
If you wanted to have a house that didn't have too much street noise when the windows were closed and you can have a really wonderful, serene environment.
14:37-14:44
In fact, a safe environment because the windows have triple pane, laminated glass, we can do passive house windows.
14:44-14:55
Then going into, now that I've got the sealed house, if you wanted to have filtered fresh air 24-7, I could use fresh air systems like we do in a lot of our passive houses.
14:55-15:01
And then once I get into that, I've reduced so much mechanicals that I barely need to heat.
15:01-15:03
I can keep the mechanicals to the center of the house.
15:03-15:05
I don't need radiators at the windows and doors.
15:05-15:10
We get to do nice big windows and doors and openings because I'm doing a passive house.
15:10-15:19
And then honestly, because of all that, it's amazing how inexpensive it is to run them in the winter because I'm now using a lot of heat and how comfortable the air is.
15:19-15:22
And it's good for the environment.
15:22-15:24
So it's a win-win, but you're getting to have your cake and eat it too.
15:24-15:29
I mean, that's in general my spiel, but I don't often get through it all.
15:29-15:30
I don't.
15:30-15:37
I think it's important to leave space between your points to allow other people to interject.
15:37-15:43
And I very often don't get past the first or second point without them asking what a passive house is.
15:44-15:48
I think it's important to mention, even though I say it's important not to talk about passive house.
15:48-15:54
I think it's important to throw the term in sometimes so that people know what you're going to be describing.
15:55-16:00
But I feel like I use it as a tool, almost like it's a quirky thing.
16:00-16:01
It's a flux capacitor.
16:01-16:06
It's a thing that people, it's a thing you can talk about, but it's really amenity rich.
16:06-16:07
It really is.
16:07-16:10
And they didn't know they can have those amenities.
16:10-16:14
And no matter how, where your price point is, people want those amenities.
16:14-16:18
And they will do almost anything to get them once they realize they exist.
16:18-16:19
Thanks for that, Michael.
16:19-16:23
And I'm sure Doc Brown from Back to the Future would approve.
16:23-16:31
Next up, we hear from Christoph Erwin, lead engineer, co-founder, and principal of Positive Energy in Austin, Texas.
16:31-16:42
Christoph is a driving force behind the biannual Humid Climate Conference that explores passive house practice in hot humid climates and is the host of the superb Building Science Podcast.
16:42-16:45
Check out this first clip from Christoph.
16:46-16:51
There's these twin things that sometimes we don't really see, kind of like a coin that you turn it around.
16:51-16:52
There's your job.
16:52-16:56
All of you have some sort of profession or had some sort of profession.
16:56-16:58
And then there's your role in society.
16:58-17:02
And it's the same thing, but it's a different way to look at the same thing.
17:02-17:20
And as soon as you say role in society, you're expressing like the paradigm of our times, which is ecosystem consciousness or something like that, system consciousness, which coincidentally is what gives the mojo, the power to building science is systems thinking, systems consciousness.
17:20-17:32
But really the way that I connect to passive house and it really just lit me up and why I'm such a devoted follower and participant is, you know, just like there's job and role in society.
17:32-17:36
There's to know how to make fantastic buildings.
17:36-17:38
And then there is to cause that to happen.
17:38-17:42
To know, to cause to happen.
17:42-17:48
And the passive house community is causing it to happen, is starting with the knowing and causing it to happen.
17:49-18:01
But generally speaking, there's this ability to take even these really profound or insightful concepts and kind of materialize them and go, oh, look, we're talking about embodied carbon today.
18:01-18:02
Isn't that a cool thing?
18:02-18:09
You know, we're talking about resilience and to treat it like it's this bauble, like this jewel that I collect this information.
18:10-18:18
And I have this wealth of information, whereas if it doesn't go somewhere, if we don't cause it to happen, its value is somewhat diminished.
18:18-18:24
There's to know how to make change and there's to cause that change to happen.
18:24-18:29
To make change, Christoph encourages us to understand and shift our paradigms.
18:29-18:35
Here, he applies that idea to a question about how to shift business as usual in HVAC practice.
18:35-18:42
But to your question, let's say you're going to try to do design build and you're going to talk to the builder about it.
18:42-18:44
The first thing you're going to do is you're going to set up paradigms.
18:44-18:47
You're going to say, look, this thing is, of course, going to heat and cool the house.
18:47-18:48
Of course.
18:48-18:51
That's not of interest to me.
18:51-18:58
I want to know how it's going to filter the air, dry the air, or maintain humidity in the air and ventilate the air.
18:58-19:10
So filtration, ventilation, and humidity control, making sure that you mention those as separate but really equally important, if not slightly more important, because you have health versus comfort in play there.
19:10-19:13
And so you just putting that paradigm.
19:13-19:14
Again, this is the power of paradigms.
19:14-19:17
Like, of course, we're going to heat and cool the house.
19:17-19:19
But how are we going to filter, ventilate, and control humidity?
19:20-19:36
And just one example, like you could, you know, and another thing you could pile on with, and when we filter the air, when do we filter the air currently mainstream across this country, is only when it's too hot and the air conditioning kicks on or too cold and the heat pump or furnace kick on, right?
19:36-19:41
So clearly, filtration in this country is currently not really about the occupant's health.
19:41-19:48
It's about, you know, preventing the, its convenience and preventing the heat exchanger from fouling or something.
19:48-19:55
So you speaking from those levels, you know, with confidence and which it's pretty easy to be confident about those things.
19:55-19:56
It is not easy.
19:56-19:59
It feels really good.
19:59-20:07
It's, we know it's important because what we do is we try to understand the local market as best we can, the distributors, the installers.
20:07-20:11
And we make different designs that are kind of like a pitch that we deliver to that project team.
20:11-20:14
And we want the pitch hit out of the park, right?
20:14-20:20
So we will downgrade a control system or downgrade, you know, we'll go with just single stage heating and cooling.
20:20-20:34
Because for us, gosh, if that's going to save some money and save some wear and tear and brain damage on the project team to not go VRF or not go hydronic, then we have the extra capacity to say, hey, now we need a ventilation system for this house, right?
20:34-20:37
Or now we need a humidity control system for the house.
20:37-20:45
And so we're really kind of customizing the designs, not just based on, you know, these outcomes, but based on what is the market like?
20:45-20:46
What is it ready for?
20:46-20:49
What seed can we plant that will grow in that market?
20:49-20:50
Yeah.
20:51-20:56
What if I were to tell you in general, my market in particular?
20:56-20:57
Oh, here's.
20:57-21:02
Doesn't appear to be ready for all the things that you just said.
21:02-21:02
Yeah.
21:02-21:04
Don't give up.
21:04-21:05
Work with yourself.
21:05-21:08
You know, find your confidence.
21:08-21:11
Find the fact that you have a commitment to these principles.
21:11-21:12
And that's that.
21:12-21:14
And, you know, don't give in to doubt.
21:14-21:16
Right on.
21:16-21:26
But it's also the case that, like, don't assume that the market is not going to be responsive to that because you're speaking in simple truths, right?
21:26-21:27
And you could do more paradigms.
21:27-21:33
Like, you could remind owners that they live immersed in air and they take it into every tissue and sell 16 times a minute or something.
21:33-21:40
You know, these 30 pounds of air a day, these like things that really kind of, oh, wait, wait a minute.
21:40-21:41
I live in air?
21:41-21:42
Air has mass?
21:42-21:45
That really helps shake things up.
21:45-21:50
And, you know, when you shake up paradigms, you're really operating at a deep level because paradigms are like these, right?
21:50-21:51
They're the glasses we don't take off.
21:51-21:53
They are our worldview.
21:53-21:56
And so your worldview is my market isn't ready.
21:56-21:59
No one really cares about this stuff.
21:59-22:00
I am the lone warrior.
22:00-22:03
You know, I'm not, you know, I've lived that, right?
22:03-22:04
We all know that.
22:04-22:06
A lot of us here are a self-selected group of these people.
22:07-22:17
And so just assume that there are a few people that are going to be nodding very much when you speak that way.
22:17-22:18
So don't give up.
22:18-22:22
I think it's a lot to do with this sort of inner space, unfortunately.
22:22-22:25
It's not as exciting.
22:25-22:29
It would be nice if there was some technology or some program or something I could send you to.
22:29-22:30
But it's up to us.
22:30-22:35
Got to shake up those paradigms, both externally and internally.
22:35-22:42
In this next clip, Christoph dives in to how to understand when active dehumidification is called for.
22:44-22:46
You can do a lot with the enclosure.
22:46-22:52
But generally speaking, what we've done is we've created a very robust environmental separator.
22:52-22:55
And so the outdoor environment and the indoor environment are communicating less.
22:55-23:01
And so if the indoor environment, the humidity loads aren't controlled, then they can cause issues with the enclosure.
23:01-23:04
And I don't know if you've heard of Ken Goering.
23:04-23:06
He was the founder of Santa Fe.
23:06-23:09
Wait, no, Thermostore, which is now Santa Fe.
23:09-23:10
Used to be ultra-air dehumidifiers.
23:11-23:15
He has this really simple, when do I need a dehumidifier?
23:15-23:20
And it's if green grass grows in your climate without being watered, right?
23:20-23:27
If at some point in the year there's luscious green grass outside, what you have is you have a high dew point condition outside.
23:27-23:32
So that means the building isn't going to be able to dry that way effectively in that time.
23:32-23:36
So generally speaking across the country right now, it's ERVs, not HRVs.
23:36-23:38
So HRVs is where it started.
23:38-23:39
It's generally ERVs now.
23:39-23:43
Few climate zones, maybe Portland, Seattle, are HRVs.
23:43-23:50
And the metric there is, is the outdoor humidity condition something I'd be okay with indoors pretty much on a year-round basis?
23:50-23:52
If the answer is yes, it's an HRV.
23:52-23:54
But the answer is typically not yes.
23:54-23:57
It's too low in many cold climates and too high in many humid climates.
23:58-23:59
Now, I want to be really, really clear.
23:59-24:06
If you have an ERV in the building, it is not going to control humidity by itself.
24:07-24:17
The motive force, the core motive force for the ERVs ability to control moisture is the dry air mass in the building, right?
24:17-24:21
So the dry in the summer, the dry, cool air mass.
24:21-24:28
The dry offsets the wet coming in and the cool air mass offsets the heat coming in, right?
24:28-24:36
So people understand it with heat, but they don't seem to understand it with dry because what happens over and over, and we've consulted on it, and it just hurts, right?
24:36-24:43
Often it's like multifamily, affordable housing, and they've said, I want to take the next step.
24:43-24:45
I care about my occupants.
24:45-24:49
I'm going to put an ERV in, and they make a good enclosure.
24:49-24:54
And so now the mechanical system doesn't run enough to keep the air dry.
24:54-25:01
It runs enough to keep it cool, but because you have a humid air mass to start with, you have humid going out, humid coming in.
25:01-25:06
You don't absorb any of the humidity on the incoming stream because the outcoming stream was humid.
25:06-25:06
Right?
25:06-25:26
So it's this really important, but it's almost like a paradigm, a principle, that when you use an ERV in the summer in hot, humid conditions, it is the dry, cool air mass in the building that you paid to cause to exist that is actually the root energy source or motive force of the ERV.
25:26-25:29
Not tricky.
25:29-25:32
It's nothing tricky, but it's interesting how often it's overlooked.
25:32-25:34
There's those paradigms again.
25:35-25:40
Speaking of which, Christoph challenges us to shift our ventilation paradigm.
25:40-25:42
Ventilation.
25:42-25:47
If you guys like, if there's a huge takeaway for the rest of our careers, ventilate too much.
25:47-25:49
You know, let's prove that too much is too much.
25:49-25:51
Right now we ventilate too little.
25:51-25:53
Our ventilation standards are still based on odor control.
25:53-25:58
And, you know, every time we look at ventilation, we realize, oh yeah, these are minimum standards.
25:58-26:03
You know, BSC has some good stuff about what we can do with it.
26:03-26:08
But generally speaking, like be a ventilation champion on your projects.
26:08-26:11
It's hugely important.
26:11-26:13
12 of these every minute into here.
26:13-26:15
And our body doesn't discern.
26:15-26:17
It doesn't say, is that a nutrient or a waste?
26:17-26:20
Like when we eat, our body's just like, this must be clean air.
26:20-26:20
It's coming in.
26:20-26:23
So the room around me is my prelung, right?
26:23-26:26
These are sorts of ways to think accurately about the built environment.
26:27-26:28
Thanks, Christoph.
26:28-26:34
Now let's pivot to Tom Bassett-Dilley and his AMA on retrofits and embodied carbon.
26:34-26:41
Tom is a torchbearer for Passive House Design who has been shining the way in Illinois for over a decade.
26:41-26:49
He's a community leader in the Phius community and a founding member and past president of the Chicago chapter of the Phius Alliance.
26:49-26:55
In this clip, Tom responds to a question about how to make Passive House retrofits work on a budget.
26:56-26:59
I guess I'll put that two different ways, Brent.
26:59-27:00
One, construction is expensive.
27:00-27:08
And what I've found lately is that, you know, owner drives up in his, you know, his Tesla or his Bolt or whatever.
27:08-27:12
He's got this amazing piece of technology in his pocket.
27:12-27:16
And he communicates with his kids in New Zealand.
27:16-27:24
And he just bought a 1904 house, which is like, it's like, you know, dinosaurs on the menu.
27:25-27:29
You know, so anyway, it's like, how do we bring these worlds together?
27:29-27:34
And so I want my house to make as much sense as everything else I got around me.
27:34-27:40
So does it make sense to let, you know, soil gas come up for the basement and moisture and all this kind of stuff?
27:40-27:42
No, that's like a stupid way to live.
27:43-27:48
And then it's like, okay, if we have some solar and we put some batteries in, I got more peace of mind.
27:48-27:51
And so the house is starting to make sense for me now.
27:51-27:55
You know, we don't know how much these things are going to cost at the outset, right?
27:55-28:01
And also we got to figure out with each building, they're all different in terms of the building science issues we got to deal with.
28:02-28:06
So anyway, we'll go into schematic design.
28:06-28:17
Sometimes we'll start with an energy auditor to come in and really get a clear view with blower door and thermal imaging, like things that we might not be seeing.
28:18-28:23
And then we'll come up with a retrofit design and the architectural renovation design.
28:23-28:32
And we'll get to schematic design as quickly and decisively as we can and get that out for budget pricing and then see where it comes in.
28:32-28:41
But for the projects we're doing that are like gut rehabs, everything new on the inside, new electrical service, new mechanical systems.
28:41-28:44
I mean, these are, you know, three quarters of a million dollars.
28:44-28:46
This is like building a new house.
28:46-28:49
But you can do it inside an old one.
28:49-29:02
And so in those cases, I find that those clients are usually a little less budget constrained than like what I did on my house, which is like, okay, my soffits are falling and my facials are falling off.
29:02-29:03
The squirrels got in.
29:03-29:04
It's time to do something.
29:04-29:08
The siding is cracked asbestos siding.
29:08-29:09
I got to deal with that.
29:09-29:13
And so I just made this list of like what I have to do.
29:13-29:17
The basement's leaky and moisture and non-insulated.
29:17-29:23
So anyway, I did all my stuff on my house for about $150,000, $175,000.
29:23-29:28
And so that's like our lighter touch decarbonization thing.
29:29-29:34
So it really is a question of, you know, how much architecture has to happen.
29:34-29:42
If you've got to do that gut anyway, then if you're not doing it like a passive house, you're just, you're not building it well.
29:42-29:50
And it's not going to cost that much more because you've got to deal with moisture, ventilation, mechanical systems, you know, insulation.
29:50-29:53
You can't, you can't just say, oh, we, we won't do insulation and air tightness.
29:53-29:54
You know what I mean?
29:54-29:57
So I guess it's all expensive.
29:57-30:00
And so if I had somebody say, I want to do a gut rate rehab, I've got $300,000.
30:00-30:02
I'd be like, I'm sorry, we can't do it.
30:02-30:04
So that's what I'm realizing.
30:04-30:12
My understanding of the costs was not in line with where we are in today's world.
30:12-30:17
Well, I mean, so there's a, there's a low hanging fruit, right?
30:17-30:20
You can blow some, some insulation in your sidewalls.
30:20-30:25
You can seal the attic and, and do some, you know, some insulation there depending.
30:25-30:27
I mean, some, some attics get very complicated, very fast.
30:27-30:30
So, and then you can phase some of that stuff.
30:30-30:38
So a lot of times we'll make like a master plan, a decarbonization plan, and we'll figure out what's on the near term and what's on the longer term.
30:39-30:50
And, and, but, but, but if you don't think all that stuff through, then, then some of that, well, some of that can get really compromised by, by a project that you do today.
30:50-30:52
So, wow, we didn't think about that.
30:52-30:55
There's no way we're going to insulate that porch now or whatever.
30:55-30:55
I don't know.
30:55-30:57
Construction is expensive.
30:57-30:58
There's no getting around it.
30:58-31:08
That said, there's low hanging fruit that we can tackle in our projects, especially if they're part of a broader decarbonization plan that helps ensure that we're not doing things today.
31:08-31:11
That make decarbonization harder down the road.
31:11-31:17
That's part of the reason that the revised Revive Standard, Phius's Retrofit Standard, is so interesting.
31:17-31:19
Here, I ask Tom about it.
31:19-31:26
Tom, you alluded to the Revive Standard and the new version of the Revive Standard, which I think is really exciting.
31:27-31:36
And it's a move to really focus on upfront carbon and resilience in deciding on what intervention to make in a project.
31:36-31:46
Could you say a little bit about that and how you foresee that potentially changing your practice or meshing with your practice?
31:46-31:46
Yeah.
31:46-31:55
Part of the way it came about, Revive, was when I started to do my house and I said to Phius, boy, would I love to make my house a Phius certified?
31:55-31:58
But I can't because I did my roof years ago.
31:58-32:00
I did these windows years ago before I knew.
32:01-32:03
And I can't afford to do those things now.
32:03-32:05
I don't want to tear off my roof and redo it.
32:05-32:16
It would really be nice if you guys want to be involved in scaling up retrofits to have the kind of technical support that you get from a FIAS certification.
32:17-32:18
But it's got to be different.
32:18-32:32
We're just going to rule ourselves out of projects because the mass of people won't be doing our 60 roofs and our 40 walls in their old bungalow or whatever.
32:32-32:35
So anyway, they were hearing it from different people, I'm sure.
32:35-32:39
But Graham and Al at FIAS figured out the new standard.
32:39-32:42
So we're doing our first project through the new standard.
32:42-32:59
And it focuses on assessing the project and then getting to that resilience question, which is, can the house, basically, instead of setting the space conditioning metrics up like FIAS or PHI does, it basically says, insulate well enough so that you can get through a power outage.
32:59-33:01
That's kind of the resilience standard.
33:02-33:12
And so you have to go and get climate information and do a simulation, basically, that they're setting us up to do to show that you'll make it through.
33:12-33:14
You know, your pipes won't freeze or whatever.
33:14-33:22
So I think the first revived project at the new standard we're doing right now, so I feel like we're a little bit beta testing.
33:22-33:25
And there's a lot of some stuff needs to be automated a little more.
33:25-33:29
Like, we have to go find wet bulb and dry bulb temperatures and stuff.
33:29-33:31
It's like, I'm an architect.
33:31-33:33
So anyway, yeah.
33:33-33:44
But the idea of it is great because it only makes sense to look out for your embodied carbon when you start to do this kind of stuff.
33:44-33:47
And when you start to do the renovations, you have to consider that as part of it.
33:47-33:57
So when they came forth with that idea, I just thought it was so brilliant that they're putting resilience and carbon together, not just operational energy.
33:57-34:02
So I'm hoping that we really accelerate this more.
34:02-34:04
Yeah, thank you.
34:04-34:06
And I'm really eager to learn about that beta.
34:06-34:09
Yeah, it's just I've been super excited to see this development.
34:10-34:15
We were fortunate to have another expert in residence, Lloyd Alter, in the conversation.
34:15-34:23
Lloyd is author of the book, Living the 1.5 Degree Lifestyle, as well as many thousands of articles at Treehugger.
34:23-34:33
I wanted to talk about, you know, Tom, the critical issue now with so many thousands and thousands of buildings that have to be retrofitted.
34:34-34:39
You know, I spoke about retrofit at the last Passive House conference in Innsbruck.
34:39-34:47
And the thing that I was talking about we have to face is there's a balance that we have to hit between heat pumpification and insulation.
34:47-35:03
That particularly if we're going to save old buildings and if we want to reduce our embodied carbon emissions, then we have to look at what point do we demand, you know, go for clean electricity and a heat pump.
35:03-35:07
And then, as you said, go back, go for the low hanging fruit.
35:07-35:15
You know, the air sealing, the insulation of basements and attics, the caulking and things like that you can do combined with heat pumpification.
35:15-35:28
I've been criticized in Passive House Accelerator by Schuyler and that about this whole attitude about, you know, you've still got to think about comfort and electricity isn't really clean.
35:28-35:36
But at some point with the embodied carbon and with the number of houses we have to do, we have to face the music on this balance.
35:36-35:43
There's a group in England, the AECB, that came up with their carbon light certification.
35:44-35:53
I think your Passive FIAS Revive looks more sophisticated because it brings this resilience thing into it, which I think is fantastic.
35:53-35:57
But this carbon light just does exactly that.
35:57-36:07
It says, OK, right now, let's lower our carbon emissions by going with heat pump and doing the easy low hanging fruit, but make provisions that down the road you might be able to want to do more.
36:07-36:13
That's just the comment I would make, that this is like a really serious compromise that it looks like FIAS is making.
36:14-36:19
And I don't know that FIAS has yet had the nerve to do.
36:19-36:20
Yeah.
36:20-36:26
I just want to feed into that because one of the things about our climate here in Chicago, and I know you're, are you in Toronto?
36:26-36:27
Yeah.
36:27-36:28
It's similar.
36:28-36:29
It gets very cold.
36:29-36:35
And so when you're in an uninsulated building or poorly insulated building, you have cold surfaces around you.
36:35-36:36
Your mean radiant temperature is really...
36:36-36:37
You know what?
36:38-36:38
MRT.
36:38-36:39
Yeah.
36:39-36:46
And so you put a radiator in that room that's large and hot, and all of a sudden, your mean radiant temperature is in a place where you can be comfortable.
36:47-36:55
So let's say we take out that radiator, we put in heat pumps, and we've got a little bit of warm air coming in, but you have all these cold surfaces around you.
36:55-36:57
You're not going to be comfortable.
36:57-37:07
So I think that some amount of insulation is needed so that you don't have a problem where all of a sudden the heat pumpification gets shot down because people are like, these don't work.
37:07-37:08
You can't be comfortable.
37:08-37:12
So like when I did it in my house, it's a 1919 frame bungalow.
37:12-37:20
I got to the R20s in the wall, like maybe 30 in the roof and, you know, 20 in the basement.
37:20-37:22
But it's continuous, and it's much better air sealed.
37:22-37:26
The house feels completely different than it did.
37:26-37:27
The first cold snap, my wife got out of bed.
37:27-37:29
She goes, wow, the floor is not cold.
37:29-37:31
I'm just like, yes, it works.
37:32-37:42
Even so, we have a pretty darn good house for a retrofit, but our thermostat with our heat pumps lags.
37:42-37:44
The capacity is there, but it'll lag.
37:44-37:49
I'll be at 64 sometimes at the 68 set point if it's 5 or 10 below Fahrenheit outside.
37:49-37:55
And, okay, we can deal with that with just one little space heater, and that's our backup.
37:55-38:03
But I guess what I'm saying is that most people don't want to worry about thinking about backup heat and all these kind of things.
38:03-38:10
So I think it's yet another complication in the whole calculus of how much is enough, you know?
38:10-38:21
That question of how to strike the balance between building envelope performance and heat pumpification cuts right to the heart of our collective work in building decarbonization.
38:21-38:23
So thank you, Lloyd, for raising it.
38:23-38:28
And thank you to Ryan, Michael, Kristoff, and Tom for sharing their insights with us this week.
38:28-38:31
As always, these clips just scratched the surface.
38:31-38:36
So if anything piqued your interest here, please do dive into the full replays of these sessions.
38:36-38:40
And if you're not a member of Reimagine Buildings Collective, please join us.
38:40-38:43
You'll get direct access to experts like these.
38:43-38:49
You'll get to know them, ask your burning questions, and expand your mind and your practice by engaging with these thought leaders.
38:49-38:53
Head over to reimaginebuildings.com to join.
38:53-38:58
Speaking of joining the collective, we've had a big influx of new members, which is super exciting.
38:58-39:28
A big welcome to Kamilia Vaneck, Xavier Obando, Juliana Renn, John Donley, Claire Tam, Nuria Widmann, Elyse Myrans, Silvia Wallis, Bill Wason, Benson Chen, Wesley Van Rite, Brendan Weiden, John Liu, Bojan Solarevic, Rayanb Ghazal, Xenia Koss, John Essig, Corey Cliffe, Randall Anway, Linda Hallgren, Kristof Irwin, Steven Bishop, Tim Harsch, Edwin Fang, Miles Tayler, and Perry Chen.
39:28-39:32
With that.
39:32-39:40
Thank you for listening to this fifth episode of the Reimagine Edit, a production of the Passive House podcast by Passive House Accelerator.
39:40-39:45
As always, don't hesitate to DM me with anything Reimagine Buildings Collective related.
39:45-39:48
What you'd like to see on the platform, any ideas you'd like to share.
39:48-39:52
We're building this community with you, so let us know.
39:52-39:55
And don't forget to invite your friends and colleagues to join us.
39:55-39:58
Thank you, and have a great couple of weeks.
39:58-39:59
Be well.
39:59-40:01
.
40:01-40:03
you