#42 | The Building Forensics Playbook with Kohta Ueno

Jess Kismet (00:00)

Hello and welcome to the Building Sciology Poddie where we talk about better buildings

 

to live and breathe in. My name is Jess Kismet and I am your host. Today we have another building science rock star on our hands. Today's guest is legendary in the building science game, not just for his brains, but his boots on the ground and knee deep in mud approach to building forensics. Kohta Ueno is the principal at Building Science Corp in Massachusetts where he spent over 25 years.

 

diagnosing why buildings fail and how to make them succeed. A protege of one of the industry greats, John Straub, Kohta brings both academic rigor and forensic intuition to the field. So I am very pleased to welcome you to the show, Kohta.

 

Kohta Ueno (00:40)

So much, Jess. Great to be here.

 

Jess Kismet (00:42)

So you started with material science at MIT as your undergrad, is that correct? And then you did your masters at the University of Waterloo. So this is a fairly robust education. Tell me about how this education made you the building scientist you are today and how this makes your approach different to us mere mortals.

 

Kohta Ueno (00:46)

That's right.

 

I do not make any great claims. just keep on showing up and getting the work done on the scale of things. know, bridging back to ancient history of undergraduate time.

 

Jess Kismet (01:04)

I

 

Kohta Ueno (01:11)

MIT is a thorough meat grinder of a school. It's just been described as trying to drink water from a fire hose in terms of the information flow. So it's pretty brutal. I would argue that part of how my education, MIT education,

 

directed me into this field is by completely burning me out during my undergraduate career and basically never making me want to do another equation ever again, frankly. So basically when I graduated, I realized what I really loved during my off time during undergrad was fixing things around the house. I ended up hanging up my shingle as a carpenter doing small carpentry and remodeling and bathroom renovation jobs.

 

you know, incredibly useful and interesting. and unfortunately I'm a terrible businessman. So I ended up living in my parents' basement after a few years. fast forward through that. And I was watching an episode of Nova. It's a public television science show on, you know, in the U S and my mentor, Joe Stebrick was actually one of the talking heads on that program.

 

Where basically he was describing how he diagnosed the indoor air quality problems at the Motor Vehicles building where people were having scratchy eyes and noses And he was the one who figured out the air leakage problem coming into the suspended ceiling that was dropping debris and causing all of those sick building syndrome problems So I cold called them and they incredibly luckily they were looking for an entry-level person right there and then so

 

Thank

 

Basically my academic education, the burnout aspect kind of brought me into this field by a very roundabout method. When people ask me, do I use my, you know, my undergraduate knowledge? Not specifically. So, you know, I concentrated in material science on, know, metallurgy, the metallurgy side of things. And so they say like, here's a corrosion problem. Can you help me with that? And my answer.

 

Jess Kismet (03:05)

Mm-hmm.

 

Kohta Ueno (03:17)

is honestly, you can read a corrosion table as well as I can. What's the potential difference between these? That's what you really need to know.

 

Jess Kismet (03:24)

Mm hmm. So I think I'm not sure I didn't use my undergrad either. And I reckon when you go to university or college, the undergrad is like, it's of just teaching you about how to learn most like unless you do it like a, you know, a doctor or an accountant, that's going to lead to a pathway. I find that if there's just a bit of a way to like allow you to grow up a little bit clearly, you know, stretch the brain and you know,

 

teach you a little bit about life, not just the topic that you're actually there to study. Yeah. Yeah.

 

Kohta Ueno (03:51)

completely agreed, learning how to think, how to solve problems, all of those

 

aspects, as well as being socialized into a greater sphere than your, you know, many of us had very, you know, channeled childhoods, I'll say. you know, open does nothing about the aspect for sure. Yeah, and as a

 

Jess Kismet (04:03)

Yep. Yep. Yep.

 

Yeah, teaching a bit of independent learning and things like that.

 

Kohta Ueno (04:11)

Big picture point, it seems like so many people in the building science field followed some kind of a strange meandering path to get here. Unlike the people who have a very distinct career path, majoring in biology during school and then pre-med and then going to med school, becoming a doctor, going all through that, more power to all the people who have that kind of a career path in mind, but that describes very few building scientists that I know.

 

Jess Kismet (04:18)

Mm, mm.

 

You're 100 % right because it's not a career path. It's not a degree that you can take and think of as a kid at uni. You don't go to the careers counselor and they say, how about you talk about mold and building failures? That's not a career path. Well, you'll get here kind of by happy accident because we realize through our other ventures, there's a real problem here. I want to know more about this.

 

So on that topic, when you talk about teaching people how to look at a house like a building scientist, so how do we do that? What's the first thing that you look for? How can we teach other people to look at buildings like a building scientist?

 

Kohta Ueno (05:12)

background, I wrote that multi-part series on Green Building Advisor and it's been published in a few spots on Basin that's called how to look at a house like a building scientist and I'm concentrating on teaching the tools that I use Just because there are plenty of things in an investigation that you cannot see But that kind of short changes people a little bit concentrating John just the tools themselves because there's a whole level of building diagnostic thinking

 

Jess Kismet (05:22)

Mm-hmm.

 

Kohta Ueno (05:41)

through the problem that you need to understand first. So big picture wise, know,

 

Figuring out what is the problem, gathering the information on the problem, those are a couple of key things. Joe Stieberich was very fond of telling anybody who he was a mentor for, talk to the people on site, talk to the people who have been living with the problem for a long time. They might not know the science behind it, but they can tell you the patterns. The guy who was mopping up all of the drips that are coming from the ceiling, he's not going to be able to tell you

 

story of the problem, but he will have some vital clues in there. These are occurring on the day that it rains, or it occurs two days after the rain, or it has nothing to do with that. It's happening on, only happening in the spring. Each of those are completely different problems from rain leakage to stored moisture to condensation issues that you would need to wrap your head around in those various cases. Another way to think in this

 

type of investigation and investigatory mode is looking at the patterns. Are the problems only occurring on the east side, the south side, all of those types of aspects? Occurring on all stories and all conditions or are they limited to like, huh, there's a weird thing going on where I'm only seeing drip marks in these patterns. Just as a really odd example of, you know, looking at patterns in general.

 

Jess Kismet (06:54)

Mm-hmm.

 

Kohta Ueno (07:09)

I was once wandering through a building where it was basically a asbestos Hazardous material remediation gone completely wrong They they tried to mask off the moisture sensitive surfaces with plastic and hit the inside with a pressure washer Which was mistake number one if you're trying to work on this They ended up flooding part of the building having it flood down through the floors Basically, they turned an asbestos remediation

 

into a rip out all of the drywall and fix the mold job. But walking around, I saw these really strange stripe and dot patterns. And that frankly was just a small, like a micro lesson that the stripes that were not growing mold is where the drywall was taped at the seams and the dots were where they basically covered the screw heads. And that was demonstrating that paper is

 

Jess Kismet (07:42)

Mm.

 

Mm-hmm.

 

Kohta Ueno (08:04)

is ideal mold food, and even the thinnest of 16th of an inch covering of joint compound could be enough to reduce how much mold will grow there. As Joe is very fond of saying, even the dumbest of the three little pigs didn't build his house out of paper.

 

Jess Kismet (08:18)

So is that because the moisture was on the other side coming through or was it just create a different property?

 

Kohta Ueno (08:23)

sorry, this was, you basically.

 

It's all of this was surface moisture on this on the basically the interior surface that you're looking at. Everything got really wet and you know was unable to dry sufficiently quickly. And as a result, and so basically mold grow grew on the paper surfaces or the painted paper surfaces, excuse me. But just that thinly skim of drywall was enough to basically separate away the paper to reduce how much mold grew at each of those stripes, for instance.

 

Jess Kismet (08:30)

Okay.

 

Kohta Ueno (08:51)

instance.

 

Jess Kismet (08:51)

Yeah,

 

right. Interesting. So,

 

Kohta Ueno (08:54)

Yeah. Yeah, but in terms

 

of

 

Like other, you know, other things for figuring out the diagnostic, how to think through the problem is, you know, con you know, there's a little bit of scientific method there of, what are you, what's the hypothesis that you're putting together in your brain of what the cause would be. And then you're constantly looking for, okay, this is going to be either inconsistent with my hypothesis or actually actively refute it. So, you know, keeping your brain open where it's like, this is my

 

Jess Kismet (09:22)

Mm-hmm.

 

Kohta Ueno (09:26)

pet theory, but I'm willing for this pet theory to die if I'm searing information to the contrary.

 

Jess Kismet (09:32)

Yeah, think one of the themes that comes up again and again in my conversations is stay curious, always question your assumptions, keep an open mind, because buildings can surprise us.

 

Kohta Ueno (09:43)

Yeah, absolutely. Just like one surprise was walking around on an investigation and somebody pointed out like, yeah, check out all of this efflorescence staining on the side of the school building. And then the school facilities guide said like, actually, that's the corner around the side door where they bang out the chalk erasers. It's like, duh, you got me.

 

Jess Kismet (10:05)

classic, classic. Back in the day huh? When we had chalkboards

 

and the nostalgia that that brings back. that's funny. Have you had any other surprises? Any other buildings where they know didn't quite go didn't quite tell you what they thought they were going to? You can think of.

 

Kohta Ueno (10:09)

yeah, forget you and the not light boards.

 

Yeah.

 

There was one,

 

know, like, so just as background, you know, my primary focus is energy, moisture. That's kind of the fundamental of building science, but the hardest problems to diagnose in general are odor problems. I don't know if you've had any guests talk to you about that, but one very big problem is they are often intermittent and they're often very subjective.

 

Jess Kismet (10:33)

of the

 

Mm.

 

Yeah.

 

Kohta Ueno (10:47)

I've had, I've walked into one building with odor complaints where I've had some people say like, oh, it smells like somebody's heating up leftovers in the break room. Like, no, it smells like bananas. And what am I supposed to do with that? Yeah. And of course, another problem with odors is that just the human senses, you go nose blind where basically if you're in the environment where that

 

Jess Kismet (10:57)

What am I looking for here? Come on.

 

Kohta Ueno (11:10)

odor is prevalent, you're not going to smell it after 10 or minutes. The reason why pig farmers can continue doing what they're doing, like, what smell?

 

Jess Kismet (11:14)

Stop smelling it. Yep.

 

Yeah, for sure.

 

Kohta Ueno (11:24)

Yeah, but a surprise.

 

happened during an odor investigation was I thought that I nailed the problem by, you know, basically proving that, this makeup air system for a kitchen exhaust had failed. Therefore, this massive negative pressure that was pulling in odors from the source was, know, we've fixed that fan, fixed the fan and the problem has gone away. A couple of weeks later, the problem still pops up again.

 

Jess Kismet (11:51)

Mm-hmm.

 

Kohta Ueno (11:52)

Um,

 

you know that, you know, like what the heck is going on? And, um, I literally ended up finding the problem by standing around in, you know, with up on a ladder in the suspended ceiling where I think the odor is coming from based on my pressure mapping. And then I start to smell the odor when somebody flushes a toilet by sheer luck. And it turned out that there was a crack on the top of a drain pipe. So there was no water leak, but.

 

every

 

time somebody flushed a toilet that pushed out a plug of foul-smelling air that then got sucked in to that contamination source. Yeah.

 

Jess Kismet (12:31)

huh. Wow.

 

Yeah, well done finding that one.

 

Kohta Ueno (12:34)

That was very lucky, frankly.

 

Jess Kismet (12:36)

Yeah, just timing. And

 

that's the other thing, isn't it too? Sometimes things can just, you know, you don't, if you don't know what you're looking for, sometimes you do just have to get lucky. Just in that exact example was yeah. That's fascinating. Okay. So retrofitting mass walls. There's a, in Australia, there's a lot of that going on right now. People are retrofitting double brick walls. They're retrofitting,

 

Kohta Ueno (12:44)

Absolutely.

 

Yes.

 

Jess Kismet (13:01)

know, cottages that are made of stone and things like this, heritage masonry buildings. They want to keep these beautiful history in these homes, but they want to make them more comfortable because they're typically not very family comfortable. So what is the safest way to insulate a mass wall? Both double brick and a single leaf masonry wall.

 

Kohta Ueno (13:21)

yes, so just to.

 

Clarify what we're talking about here for your audience. You know, when I think of mass masonry walls, at least in the North American context, I'm thinking of solid multi-layer brick walls, typically in New England or the Midwest of the United States. We're talking three or more layers, three or more whites of brick. The classic mill building, university building, those kinds of things. What you're describing for Australian construction, it sounds like too

 

Jess Kismet (13:31)

Mm-hmm.

 

Thanks

 

Kohta Ueno (13:51)

is more common for residential? Is that what you're saying? Yeah.

 

Jess Kismet (13:55)

Yeah, we don't have three-leaf brick walls. We have double brick and occasionally

 

like Bessa block, like heavy block walls.

 

Kohta Ueno (14:04)

Okay, gotcha, gotcha. So as you know, so once again, to talk through background to make sure we're all talking about the same thing. Mass masonry walls have no actual water control layer or drainage plane or water resistant barrier. I don't know what the Australian term might be. okay.

 

Jess Kismet (14:06)

Yeah.

 

Mm-hmm.

 

Mm-hmm. Yeah, similar. We're with you so far.

 

Kohta Ueno (14:28)

Yeah, so

 

basically the way that they work is when it rains, basically the moisture hits the surface of the brick or block, it soaks into it, and then later on over during more favorable conditions, those during dry conditions, the moisture evaporates outward back through. But during that intervening period, the moisture is stored safely within the brick or the block without any damage. You you can put a brick in a bucket of water and it won't get damaged.

 

a stud wall with OSB sheathing, it's going to go south on you. So that's the fundamental way that they work. So part of the secret of how they work is the thickness relative to the amount of rain. So that's kind of why I'm used to seeing a triple white wall as basically, historically in New England, they figured out go three, four brick layers of brick. That's enough so that during the worst rainstorms that they see in New England, you probably won't see dripping come from the inside because brick

 

Jess Kismet (15:00)

Mm-hmm.

 

Kohta Ueno (15:26)

walls are porous to water. Anybody who has stood on the inside of a single white brick veneer during a spray test will tell you that you start to see little drips of water coming through within two, three, five minutes, something like that. So each of those layers are porous to water, but you combine enough of them, they'll soak it up and keep that from actually dripping to the inside. a whole lot of background before even talking about the insulation problem.

 

Jess Kismet (15:42)

OK.

 

Mm-hmm.

 

Kohta Ueno (15:55)

So, when you insulate one of these walls, you always have the choice of going on the outside or the inside. The outside is always going to be safer full stop. And whenever I am dealing with a ugly 1970s building that people want to retrofit with insulation, that is a mass brick, brick or masonry wall, I tell them like wrap it with

 

exterior insulation, know, synthetic stucco, a panel job, something along those lines. That's always going to be better in terms of thermal performance and moisture safety. But then again, you go to a lot of historic buildings and these are beautiful resources that are part of the fabric of the town. The facade is incredibly critical. you know, there's no way that anybody could, you know...

 

Consider destroying that type of facade and covering it up with something significantly less decorative. you know, it's it's a it would be a solectomy on a building along those lines in a lot of cases. So you can insulate on the inside of the building. The problem is that when you insulate on the inside in a heating dominated climate like New England, the Midwest, the North in the United

 

States, you are reducing how much heat is flowing through that wall, which is great for your utility bill, your energy use, and bad for drying ability. Remember that because this wall relies on drying out later on, if you've reduced how much heat flows through it, you've reduced how much it can dry. So therefore, what you want to do if you're even considering

 

Jess Kismet (17:36)

Mm-hmm.

 

Kohta Ueno (17:41)

insulating one of these mass masonry walls is you want to look very carefully on is this wall getting wet, significantly wet, and address that before even considering.

 

doing interior retrofit insulation. Disconnected downspouts, roof wall intersections that's pouring water onto the wall, splash back at the ground, bad drip edges or parapets, all of these things can dump disproportionate amounts of water on the wall. Basically, I have people arguing about what are the various insulation options on the inside, and I tell them, stop, stop, stop,

 

Jess Kismet (17:55)

Mm-hmm.

 

Mm-hmm.

 

Kohta Ueno (18:20)

Before you're even thinking about this, deal with the water on the outside. Then we can start to have that conversation of how to do the interior insulation.

 

Jess Kismet (18:28)

So we're not just worrying about rain, we're worrying about, like you said, like drainage off the house, downpipes, e-depth, overhang depth, all those sorts of things as well.

 

Kohta Ueno (18:39)

Absolutely.

 

You know anything that concentrates water and sends it on the house or grade contact conditions If the ground is wet and you're wicking water up through your brick, I've seen plenty of of damage As well as just to kick out another potential damage mechanism There's snow and you and de-icing salts in much of the Northeast where people cover their sidewalks with salt to melt the snow and keep people from slipping and falling

 

Jess Kismet (18:44)

Well.

 

Mm-hmm.

 

Kohta Ueno (19:06)

that can cause a massive amount of damage to bricks and stone in a short amount of time causing, you know, once again, a whole lot of damage. that's yet another mechanism to worry about.

 

Jess Kismet (19:16)

Mm.

 

Interesting. We don't have that problem in most of Australia. We don't have snow and ice except for, you know, up in the mountains in New South Wales and places like that. But that's an interesting unintended consequence, isn't it? Melting the snow with salt, but salt absorbs moisture. So it's going to sit there and then wick up into the bricks. Is that what happens? Yeah, wow.

 

Kohta Ueno (19:22)

yeah.

 

Yeah,

 

basically, are basically the salt causes strange osmotic pressures going on. And I have seen cases where the entire outer half to three quarters inch of the brick has basically fallen off where the truck has come by with deicing salts every winter. And, you know, it's just degraded it all over time. Yeah. Yeah, you're destroying your wall, you know, just so you know.

 

Jess Kismet (20:00)

You gotta ring up the council's coder and be like, my dude, you're making a mistake.

 

Yeah,

 

yeah, just so you know.

 

Kohta Ueno (20:09)

Yeah. So like

 

I have to couch some of my recommendations with a few.

 

caveats that like I'm coming from a northeast cold weather perspective. You know, if it's a lot milder of a climate, a lot of these fundamental problems are reduced. Like the classic thing that I'm looking for for mass masonry buildings is are we going to make freeze thaw issues worse, where basically you see the surface of the brick popping off. And there is, you know, there is a potential risk of that once you insulate on the inside, the brick is colder. The idea though is

 

Jess Kismet (20:19)

Yeah.

 

Mm.

 

Kohta Ueno (20:44)

For freeze thaw to happen, you need the brick to get very cold. We're sub 20 degrees Fahrenheit range up and down, well below the freezing point, as well as having the surface be wet, very wet. We're talking soaking in a bucket wet, and that would cause freeze thaw. if you don't have many freezing cases in Australia, freeze thaw is no longer

 

an issue at all.

 

Jess Kismet (21:09)

No, I mean we have

 

we do have some frost issues in even in Adelaide in the winter we can get below zero, not usually not too below zero like at zero minus one Celsius so around about I don't know 25 degrees maybe Fahrenheit I'd guess 30 degrees. What was I going to say we do have we do have

 

In parts of Australia, we have not so much frost, humidity issues. I did a, I guess I did a Wolfie assessment last year for a client who was wanting to insulate. It was a brick veneer, so brick leaf timber stud construction. It was uninsulated. And he's like, if I insulate this, am I going to cause a huge problem? And Wolfie just threw it in the bin. It was like, this is terrible. You can't do this. You can't put insulation in the stud.

 

because of all the humidity that was in the air and in the cavity it was just basically saying there's just too much moisture here and something's going to go mouldy. So what what do you say to that?

 

Kohta Ueno (22:11)

Yeah, that sounds like a very strange outcome to me, just given that I think of a brick cavity wall, well, a stud frame wall with a brick veneer and an air space to be, you know, a pretty known quantity and, you know, insulating that is pretty much an off the shelf solution overall. Not to bore your audience with the nerdery, but just curious what you were using for...

 

Jess Kismet (22:20)

Mm.

 

Brazilian.

 

Mm.

 

Mmm.

 

No, please do. That's why we're here.

 

Kohta Ueno (22:37)

Okay,

 

like ventilation terms inside the brick air cavity, that kind of thing.

 

Jess Kismet (22:43)

Yeah, yeah, there was a lot of variables,

 

but basically, it was just telling me that there's a relative humidity and average relative humidity throughout the year of 70 % plus. And it was just not happy. The bricks were, you know, pushing moisture into the wall when the sun came up moisture, know, because we couldn't get a membrane on there because it was a retrofit. And the solution ended up being

 

Kohta Ueno (23:07)

Okay.

 

Jess Kismet (23:08)

coding the bricks with like a, I think it was a, it was a render product. So that's correct. That's correct. That, that seemed to fix the problem. So the problem was obviously coming from outside and there was a lot of moisture held in those, in those bricks. So is that if we're internally insulating and this goes for,

 

Kohta Ueno (23:13)

Okay, yep. Reducing the absorption of the brick. Yeah.

 

Jess Kismet (23:32)

I guess warm humid climates as well as cool climates. This in the answer is probably going to change. if we're talking about rain on bricks and their very porous material, they absorb a lot of moisture, is sealing the outside of a brick wall or a massive wall in a retrofit a good idea to stop the water getting into it or?

 

Kohta Ueno (23:50)

Yeah, I'm sorry, I'm going to have to give the classic engineer answer of it depends and I can't say for sure. So, Joe Steberg has a delightful article called how buildings age, of basically showing the evolution of buildings where, know, Hey, it's a brick building and with leaks all the time. So historically painted them. People have put on a stucco render. you know, and that definitely does reduce rainwater absorption, but there

 

Jess Kismet (23:54)

Yep. Yep.

 

Mm-hmm.

 

Kohta Ueno (24:16)

definitely are you know are there cases where you paint a building and all of a sudden it starts blistering all over the place? Yep those cases all do occur. You can try to counteract that by having a more vapor open paint which might or might not be enough. know if the question might be if water is getting in somewhere else and trying to work its way out it's a recipe for problems. You know I dealt with a case where

 

Jess Kismet (24:23)

and

 

Kohta Ueno (24:44)

York State, they recently recoded their Madison Masonry building with another coat of a breathable coating. And all of a sudden, they started getting these giant blisters filled with white minerals. When you like peeled back the blister, you could basically scoop out little bits of mineral staining. And the reality was, did the coating reduce how much water got through the wall, the face of the wall? Yes, absolutely. Was this coating breathable as in allowing some drying? Yes.

 

Jess Kismet (25:01)

Mm-hmm.

 

you

 

Kohta Ueno (25:12)

However, they were letting too much water in at the top of the wall which worked its way down And you know once again looking at the patterns where the book here's all along those parapets So basically water is getting in through the top and the parapet walls you trying to work its way out and Basically, it's only so breathable is what I would say about the coding you can

 

Jess Kismet (25:17)

I don't know.

 

Mm-hmm.

 

Mm-hmm.

 

Yep.

 

Kohta Ueno (25:38)

release so much moisture before it starts to blister and blow off on you. Yeah. Yep.

 

Jess Kismet (25:43)

Yep. Buildings will surprise you.

 

Kohta Ueno (25:47)

Yeah, and

 

returning to a previous topic where you're talking about inward vapor drives, like that absolutely is part of the problem. So basically the way that I always describe it is think of a brick as a very dense sponge on the outside of your building. And you go ahead and heat it up and, you know, put that wet brick in the sun, moisture will blast off both inward and outward. Inward is the direction that we're always worried about.

 

But the thing is, I typically only see problems with that when there's something that's completely stopping that moisture moving through the wall, that inward vapor drive through the wall. Like, for instance, a recipe for disaster is brick veneer, airspace, a super vapor open sheathing like in the US it's a historic product called wood fiberboard. I don't know if there's a similar one in Australia. Insulated stud wall and

 

a plastic vapor barrier on the inside. Yeah, I don't know if you've ever seen those survival stills where you have like a sheet of plastic trying to capture evaporated water, but basically you've built one inside of your wall is how I would describe that assembly. And basically a builder in Ohio went completely bankrupt by building their walls that way.

 

Jess Kismet (26:53)

Mm.

 

Yep.

 

Kohta Ueno (27:05)

Takeaway is inward vapor drive happens. It happens because there's an impermeable layer in that sandwich that's stopping the water. So it could be a dumb polyethylene vapor barrier. It could be if your client decided to put floor to ceiling mirrors on their home gym, for instance, glasses are perfect.

 

Jess Kismet (27:23)

Mmm.

 

Kohta Ueno (27:25)

It could happen where you have an art collection and you have glass faced photos on the wall or cabinets with melamine impermeable backing. Those are all possibilities. But typically if your interior side of your wall is a vapor open enough, you should be able to dry that inward. The way that I describe it is that the catastrophic flood is not caused by the river flowing through it. It's caused by damming up the river first.

 

Jess Kismet (27:38)

interesting.

 

So what if the internal plasterboard or drywall is painted with something not impermeable? Same?

 

Kohta Ueno (27:59)

Yeah, at that point,

 

you know, like oil-based paint on the inside of plasterboard, like, that's an edge case I have not, I've never modeled myself, but it does not bode well, is how I would put it.

 

Jess Kismet (28:09)

Okay,

 

so what about putting insulation in the cavity of a double brick wall in the middle?

 

Kohta Ueno (28:14)

Yeah,

 

sorry. Let me make sure I understand. This is two brick walls separated by an airspace. Is that what we're talking about? Okay, I'm sorry.

 

Jess Kismet (28:22)

Yes, yes so a lot of the

 

1960s 70s homes have been built with two leafs of brick and then people who move into them think well we'll just blow some insulation into the cavity to make it more comfortable. What's your comment on that?

 

Kohta Ueno (28:29)

Yes.

 

Yeah, I would not.

 

Yeah, that would make me nervous in general. once again, a Joe Stebrick column where he basically cites Vitruvius from, you 2000 years ago, stating like, how do you keep brick walls dry? You build two of them and you put an airspace in between them because basically that outer leaf is porous to rainwater, like we described, and we're letting the water penetrate through, drip down and come inside. And if you infill that cavity with

 

Jess Kismet (28:38)

Mm.

 

Kohta Ueno (29:04)

insulation, you've basically slushed it solid and removed that drainable air cavity.

 

Jess Kismet (29:10)

Mm.

 

Kohta Ueno (29:10)

I wouldn't,

 

I do not have enough experience with these to say, my God, it's an automatic failure, but it definitely makes me nervous. And I have a specific case study in mind where there were a school building, you know, once again, solid brick, but with an airspace somewhere in that sandwich. Top floor was leaking water because, you know, through the walls, because that's where the majority of the rain hits. And the people

 

Jess Kismet (29:19)

Yeah.

 

Kohta Ueno (29:38)

in that school district said, well, we have this air cavity. Let's go ahead and pump that full of, you know, a cementitious grout and that'll stop the water. And surprise, surprise, the problem just ended up getting worse and moving to other spots instead. So that's what, you know, that was my instructional background case of the problems that can be caused by that.

 

Jess Kismet (29:53)

Yep.

 

Yeah, it's definitely a question I get asked semi regularly. So to summarise this, external insulation is best. It's often not possible though, because people have facades they want to keep or you know, it's just tricky. Internally, good idea, but take care of the water on the outside as a priority. Middle of the cavity, probably don't do that.

 

Kohta Ueno (30:10)

Yes.

 

Absolutely.

 

Absolutely.

 

If somebody has more of a track record than me on this, I'd love to know their experience, but it does not give me a warm fuzzy.

 

Jess Kismet (30:30)

Mm-hmm.

 

even in cold climate, warm

 

climate, humid climate, all of it, you know.

 

Kohta Ueno (30:37)

Yeah, anywhere that it rains. Okay, if you're building this in Los Angeles or Phoenix, might be, frankly, you can get away with anything in terms of rain control. You know, I've gotten asked to review buildings in Los Angeles and my response is like,

 

Jess Kismet (30:39)

Yeah.

 

Kohta Ueno (30:55)

why do you care about rain? never rains here. Basically, problems are caused primarily by Los Angeles architects doing work in other climate zones and not adapting accordingly.

 

Jess Kismet (30:58)

Okay.

 

Interesting, I did not know that. I did not know that Los Angeles and Phoenix don't get much rain. Totally different.

 

Kohta Ueno (31:11)

Yeah, basically those are the

 

desert portions of the United States.

 

Jess Kismet (31:16)

Makes sense. Those architects would not be that well versed at all in the kinds of moisture issues. That's interesting.

 

Kohta Ueno (31:24)

Or they've probably worked within an ecosystem where they can get away with many things that are not possible in other rainier climate zones. And also I'm probably being a little bit facetious in terms of the broadness of the brush, just because there are absolutely are levels of knowledge here that there are ones who do know the risks they are getting into for sure.

 

Jess Kismet (31:29)

Mmm.

 

Yeah.

 

Yeah.

 

That's close.

 

Of course, of course.

 

Kohta Ueno (31:52)

and just to wrap

 

up the last piece of this, when we're talking about insulating a solid mass masonry wall, our recommendations in any climate that has cold weather condensation risks is you want to have something that keeps that interior air away from the cold masonry surface. In New England, using spray foam or rigid foam on the interior of the masonry,

 

is a pretty common solution. There are options of doing it with fibrous installations like cellulose or mineral fiber, but you have to be a lot cagey and a lot more concerned about how good your interior air barrier is and how well it controls that movement of interior air. The other beauty of closed cell spray foam and rigid foam boards is that, you know,

 

For you know for every 10 year, you know for the 10 year period between massive hurricanes hitting your building You're not gonna see any water coming through that wall But you have a massive storm that has little trickles of water coming through your mass masonry wall at that point you'd prefer to have a material that is not sensitive to water and in that case the rigid foam board or the spray foam both have lower risks in terms of will this grow anything? Nope. Will it be degrade?

 

by water. Nope. So that's kind of the reason behind that being the go-to solution.

 

Jess Kismet (33:13)

Mm-hmm.

 

So there's a bit of way up process, I think, when it comes to choosing insulation, or at least in my mind, that's why I'm asking you. So from a non-water sensitive material like a foam, we don't use spray foam in Australia very often. We usually use rigid boards. And that is a common go-to for insulating internally on masonry walls. Or we would use something like a wood fiber board, which is more vapor permeable.

 

And it's a question, which one's better? Which one would be better? Or a rock wall, that's not water sensitive, but it's also vapour permeable. So would that be like?

 

Kohta Ueno (33:53)

Yeah, all of these solutions can work. Like I'm thinking of the pros and the cons, kind of walking through those three different materials. Both the rigid foam and the rock wall, the semi-rigid rock wall have the advantages of having a little bit more resistance to water. Wood fire or depending on the type of product, whether it's wax treated, might shed the water or might become a little bit funky for sure. In terms of vapor permeance, absolutely agreed you have the advantage goes to the non-foam option.

 

Jess Kismet (34:00)

Mmm.

 

Mm.

 

Mm.

 

Kohta Ueno (34:23)

at those points.

 

Jess Kismet (34:24)

Mm.

 

Kohta Ueno (34:25)

Frankly, I've, you know, thinking through the problem and making sure you understand it holistically is very important. I once dealt with a existing mass masonry building, Massachusetts, where they insisted on using open cell spray foam, the vapor permeable version of spray foam, on the inside of the brick and block wall because they were insisting that we need to have inward drying. I got to the site and I realized that the entire inside

 

of that wall is covered with a black asphalt coating. We lost that battle back in 1925, and apparently this wall has been just fine without inward drying all that time.

 

Jess Kismet (34:57)

Redundant.

 

Right, okay. The other comment you made about the cool surface of the masonry, guess this is something that we, it's a question that comes up when we talk about insulating the internal side of a brick wall. What's the risk there? do we know when you're putting rigid foam up, for example, how important is it to take the joints, make sure that no air is getting to that internal surface of that that mass wall?

 

Kohta Ueno (35:27)

Yeah, so in a cold climate where there's a condensation risk, that's absolutely vital in terms of preventing condensation at that interface between your masonry wall and your rigid foam, for instance, or your interior insulation. In warmer climates where there's no condensation risk, possibly not as critical, but the question devolves then to, okay, where's your air barrier? Are you painting on an air water control barrier on the inside of your masonry wall? Or are you relying on that

 

Jess Kismet (35:33)

Mm-hmm.

 

Hmm.

 

Kohta Ueno (35:56)

foam as a rigid air barrier material because we ought to have an air barrier in here somewhere for sure. And a reality is that unpainted brick masonry is definitely not an air barrier. There's 1960s Canadian research where they actually went and tested that and it's, know, 0.25 CFM, you know, 50, I think, or something along those lines. It's, you know, actually measurable leakage through unpainted

 

Jess Kismet (36:11)

and

 

Mm-hmm.

 

Kohta Ueno (36:25)

painted brick.

 

Jess Kismet (36:25)

Mm-hmm. So air barrier on the inside before the insulation.

 

Kohta Ueno (36:29)

Either air barrier on the masonry before you start your installation process or make a air impermeable material like rigid foam into your air barrier by taping all those joints as you... Yeah.

 

Jess Kismet (36:40)

Right, okay, all right.

 

Thank you. I hope we covered that thoroughly enough. All right. Now another complicated topic. I don't know. It's not easy to cover this one in a less than one hour podcast, but vented and unvented roofs, pros and cons. Can we summarize this for the audience?

 

Kohta Ueno (36:46)

Yeah.

 

Yes. Yeah.

 

Sure.

 

And, you know, once again, I apologize if I might be losing some of your audience, given that I'm North American based and I know exactly this is construction that I know. So whenever I give, start my lecture on attic and roof construction, I tell people if you want a durable, moisture safe, high, you know, good energy performance, a roof system, a vented attic where you have, you know, basically a triangular space where you're walking

 

Jess Kismet (37:08)

Yeah.

 

Kohta Ueno (37:29)

around with you can see the underside of the roof sheathing. You look down and you see insulation down at the attic floor. That is the ultimate for durability and performance, frankly, especially in a cold climate. that is key. Part of the key is that we have a bulletproof airtight layer air barrier down at that attic floor. It has not been turned into Swiss cheese by recessed can, you know, light fixtures, electrical

 

Jess Kismet (37:57)

Mm-hmm.

 

Kohta Ueno (37:57)

boxes, know,

 

ceilings that pop up and down all over the place, stud walls that are poking through it. All of those have the potential to basically negate an effective air barrier down at your attic floor. But the tendency in North America in many cases is, this is an empty space that we're not using. We are going to put our heating and cooling system, our air handler furnace, and all of the ductwork up

 

in the unconditioned attic. This is historically done for very long time and is incredibly dumb. You are putting the most critical portions of your building, your heating and cooling system, in a location that gets screaming hot in summer and freezing cold in winter. So our takeaway is if you can't convince people to move the space conditioning system out

 

of that screaming hot attic, go ahead and run insulation up at the roof line instead of the attic floor, including that triangle within the conditioned space. And then you have basically brought the entire ductwork system into the conditioned space. It's running within a few degrees of interior set point.

 

Jess Kismet (39:04)

Mm.

 

Yep.

 

Kohta Ueno (39:14)

The problem is if you just throw bat insulation up into a roof line, that is a recipe for causing problems. We've done a multiple multi-year studies on this problem. The takeaway is that if you want to do it in North America, at least in a moisture safe and code compliant way, spray foam up against the roof deck is a straightforward, time proven and workable solution. Is it expensive? Yes. Is spray foam in

 

environmentally damaging material. Yes, it is. Would it be nice if there were better methods? Absolutely. But historically, what has ended up working in general is going with some type of a foam solution. There are also solutions where you can put insulation on the top side of a structural deck, similar to a commercial roof where you have layers of foam board with a roof membrane. But that is asking an awful lot for residential contractors.

 

in many cases.

 

Jess Kismet (40:11)

Yeah.

 

Kohta Ueno (40:12)

So is that, know, so I'm starting to dial in the problem. Is this the direction you're looking your talk and dive into?

 

Jess Kismet (40:18)

Yeah, yes. What's happening just

 

on that insulation at the roofline topic, it's becoming more more common in Australia for builders to, we don't have spray foam like I said, but the builders are like they're moving the bats from the ceiling to the top of the rafters, of the truss, the top of the roofline.

 

Kohta Ueno (40:23)

Yeah.

 

Yeah. Yeah.

 

Jess Kismet (40:38)

So that is something because of the air conditioning ducting and everything, keeping it inside the thermal envelope is becoming a preferred method. So that's one way that builders in Australia are moving towards sort of better building methodologies. My question is, because we have this battle sort of, not battle,

 

raging. guess just a bit of confusion in Australia because in the last building co-change or a couple ago, roof ventilation requirements were introduced for our cooler climates and we often have a mixture of roof-oid roofs and skillion roofs and the ventilation requirements are different.

 

Kohta Ueno (41:18)

Sorry, I missed those terms you were describing the two roofs. Yes.

 

Jess Kismet (41:21)

like a roof void, like a truss roof with a roof like an

 

air, you know, like a triangle type roof and a skillion, which is more like a cassette roof so that the roof is raked, the ceiling line is raked, is on an angle for architectural reasons.

 

Kohta Ueno (41:33)

Okay, sorry, I got rid of that

 

term. Basically, it's a compact assembly where you have ceiling finish insulation and air cavity, something along those lines. Okay.

 

Jess Kismet (41:42)

Yeah.

 

Yeah, yeah, that's right. So we have

 

all these different ways of, and they're often in the same house because some, there'll be some, because the roof void design is cheaper than a, like a raked angled type cassette type roof. And they often, they'll have like a skillion roof in like a living area, for example, and then the bedrooms will have flat ceilings. So there's this combination of roof types that have different ventilation requirements.

 

And Joe, I had Joe on the podcast back when I very first started. He was one of my first handful of guests and he threw a bit of a cat amongst the pigeons and said, don't vent your roof. And in Australia, we're all about, we're all trying to get our heads around how to ventilate our roofs. So I guess my question is based on that statement and the confusion we're currently experiencing here about how to do it.

 

Kohta Ueno (42:19)

Fantastic.

 

Mm-hmm.

 

Jess Kismet (42:35)

And Joe's statement was actually around fire resilience, but they'd just been the California fires. And we were sort of having a bit, I think we're having a bit of a discussion about that. yeah, he made a statement about not venting roofs and it confused a few people.

 

Kohta Ueno (42:51)

Yeah, so specifically to fire, ventilation is basically a burning ember capture device. So that lines up with why you would want to prevent that.

 

Jess Kismet (42:57)

Mm.

 

Mm.

 

Kohta Ueno (43:02)

In general, roof ventilation is a useful tool in the toolbox for colder climates and preventing moisture problems. That is true. Whether it does as much in warmer climates, yes, you can argue that it makes the roof sheathing a little bit colder, but if you have a full layer of insulation below that, it might not really matter that much on the scale of things.

 

Jess Kismet (43:24)

Mm-hmm.

 

Kohta Ueno (43:25)

Yeah, all you know, we've done like I said, we've done a bunch of research on removing ventilation in cold climates and some warmer climates and the thing is you can still sometimes get edge cases with Where you run into problems removing ventilation in warmer climates, you know It could be made up for with various features like what we call a vapor diffusion port some way to let the roof dry out as well as trying to You know dehumidify the air

 

within that attic, but that's a whole, like, I can pretty much give an hour discussion on that topic alone, for instance. Absolutely. Yeah.

 

Jess Kismet (43:59)

I know. You could do a PhD just on roofs. There's so much to know and think about.

 

Kohta Ueno (44:09)

Yeah, one of the things to remember about roofs is that, you know, as a big picture thing is because they face the sun, they are seeing the most energy compared to walls or, you know, even less foundations. Just think about the amount of heat flux going in and out of roof assemblies. So, you know, we had problems in North American open cell spray foam roofs where you

 

People

 

go up into their attics in those conditions and they're saying, why is it 70, 80 % humidity up in this space? And we've ascribed that to what we call ping pong water of moisture being driven out and sucking back into the roof sheathing. And because the roof faces the sky, it sees an incredible amount of sun and solar energy. And that is the force that is blasting out the moisture and causing this type of a ping pong problem.

 

Jess Kismet (44:52)

Mm.

 

Kohta Ueno (45:05)

I often refer to roofs as, you know, solar-driven moisture concentration machines and all of the problems that can result from that.

 

Jess Kismet (45:13)

Yeah, indeed, In our cooler climate zones, we have eight. So in the coldest three, we have to our roofs. We've been given certain sort of square millimetres per metre openings at the low point and the high point that builders have to achieve when they are building their roofs.

 

requirement conflicts with sort of what when builders are trying to achieve airtightness on the outside of their structure, it conflicts and then they get confused about how to do both and they have to compromise one for the other and but if we seal up our attic are we going to get a horrible mold problem but I want to do this. So yeah what do you have any any feedback on that?

 

Kohta Ueno (45:51)

So like in North America, we refer to the compact assembly where it is interior finish, insulation, air gap with ventilation, structural sheathing, and then your roof cladding. We refer to that commonly as a cathedral roof, a vented cathedral roof.

 

Jess Kismet (46:06)

Yep, we use that terminology.

 

Kohta Ueno (46:08)

Yeah, okay.

 

And basically they work in terms of moisture, in terms of energy, you're taking a hit because you have less space for insulation. And in terms of air tightness, are absolute, they are not always, but very often absolute disasters because you only have one spot to get your level of air tightness and that's your interior finish. And once again, if you fill that with recessed light fixtures and other items,

 

like that, that is how you have a, you you only have one chance to get it right, unlike a wall where, you you have exterior sheathing, interior gypsum board, and between the two, that could work out typically. In the case of the vented cathedral roof, one chance to get it right, and if you have a hole through your interior drywall, it is sailing up through your ridge vent out to outside. So.

 

Jess Kismet (46:42)

Mm.

 

Mm.

 

Kohta Ueno (47:02)

That's the air tightness problem that we talked about that you mentioned for sure. There are solutions out there, for instance, building a false cavity inboard of that cathedral assembly where you have a continuous layer and then all of your bric-a-brac and your lights and wires and speakers inside a cavity that is inside the air barrier. That is a good solution. Is it more layers? Absolutely.

 

Jess Kismet (47:07)

Mm.

 

So there's a company here, it's a German company that distributed their products now in Australia and New Zealand called Proclima. I don't know if you've heard of Proclima.

 

Kohta Ueno (47:37)

They're

 

European based and they sell in North America through companies like 475.

 

Jess Kismet (47:42)

Yes, yes, of course I do. Of course I do. Yes, I've seen their social media posts. So we have those products here and they have become a sort of a solution for air tightness issues with that, know, false ceiling, vapor barrier above the false ceiling and external membranes as well. The external membranes has been a bit of a game changer in Australia because it creates a continuous layer on the outside of the structure rather than

 

you know, using what we call a roof blanket. You guys don't use them over in America, but they're like a foil-backed bulk insulation that go underneath the roof sheets. And that's supposed to keep the roof sheets warm so they don't condensate and provides a little bit of, it's supposed to provide a little bit of thermal benefit to the house itself. But on the flip side of that, once you ventilate that roof cavity, then the thermal benefit of that insulation at the roof level is pretty much wiped out, right?

 

There's air movement underneath it. Yeah, So yeah, those external membranes, the membrane systems have changed the way houses are being built in Australia, which is a good thing, but they're still transitioning. So yeah, it causes a bit of confusion about how to achieve it correctly.

 

Kohta Ueno (48:34)

It's bypassed, that is true.

 

But you know that the classic spot where the detail falls, you know, like I completely agree with exterior air barriers. My go-to in North America, self-adhered vapor permeable membranes. Basically, it's, you know, trying to put an air barrier on the inside is possible, but it's a lot more difficult. It's a lot more work. On the exterior, it's a lot simpler to just have a continuous line. You could send your worst employee just to feel the entire building to look for gaps that somewhere.

 

Jess Kismet (49:02)

Hmm.

 

Mm.

 

Kohta Ueno (49:21)

mist, for instance, and they'll probably find anything. The tricky bit was transitioning to a vented attic, for instance. The detail that a bunch of practitioners have done is what I call the bridge membrane, where you basically, before you tilt up your exterior wall, you'll have a little flap of membrane over the top of your wall top plate, and that basically passes your exterior air barrier to the inside of your ceiling.

 

Jess Kismet (49:22)

Yeah. Yeah.

 

Mm-hmm.

 

Yeah, yeah,

 

we call that connection strips. So yeah, yeah, yeah. But again, a lot of builders don't know about connection strips. They don't know about air barriers. They don't know about continuity. They don't know about these things. So this is something that we talk about and try to encourage. And, you know, it changes the way the frame grows up. It changes a lot of things about the sequencing of a project as well. So it's a, it's a big shift. But it's happening amongst some Australian builders and it's, it is great to see. Okay. I'm not.

 

Kohta Ueno (49:50)

Okay, yep, there you go.

 

Yeah, training a workforce is

 

always challenge.

 

Jess Kismet (50:16)

Pardon.

 

Kohta Ueno (50:17)

Yeah, training a workforce is always a challenge, especially in new techniques. Absolutely.

 

Jess Kismet (50:22)

Yeah, yeah, it is, but it's very fulfilling. And once the builders understand that there is a better way to do such and such, they're usually really on board and they're usually really, really keen. So it's quite a space to be.

 

Kohta Ueno (50:36)

Absolutely, and also builders are smart. They're trying to figure out the problem and if you give them the proper tools to feedback, they will come up with a better solution than you is what I found.

 

Jess Kismet (50:40)

Yeah.

 

Exactly. Yeah, exactly. Fantastic. I don't know if we could really talk a lot more about Roos. We could go a lot more into depth about it, but we won't today. I hope that that discussion made enough sense for the people listening. I hope that they took something away from that. So we'll move on to the next question.

 

You use a lot of diagnostic tools in your work, a lot of different equipment. What's your favourite? What's your kit consist of and what's your favourite?

 

Kohta Ueno (51:12)

The kit that I bring to most of my investigations, a camera, an infrared camera, moisture meters of various sources, various types, little water squirt bottles if I need to inject water at one specific point to see if it comes out later, some minor disassembly tools just so I can pop out an outlet or to look behind the wall, see what I can see behind the wall or just get a little bit of access. All of those things would be typical.

 

items

 

that I bring along with me. If I had to choose a favorite out of those, probably the infrared camera would be a winner in terms of the interesting information that you can sometimes gain. People often say, what can you see with an infrared camera? Do you see ear leakage? Do you see moisture? Do you see thermal bridging? It's like, yes, but you can see it, but you have to catch it at the right time.

 

Jess Kismet (51:43)

Mm-hmm.

 

Yeah.

 

Kohta Ueno (52:07)

There is an entire season where an infrared camera will not tell you very much, which is beautiful weather where it's 70 degrees Fahrenheit inside and 70 degrees outside is like, what? Leave the camera at home pretty much.

 

Also moisture if the moisture problem has mostly no come to room temperature You might not see anything in an infrared camera for instance, you know You're relying on the evaporative cooling of that moisture to change and or the thermal mass of that water to You know basically make it show up as something different a warm spot or a cold spot on an infrared camera

 

Jess Kismet (52:31)

Mmm.

 

Kohta Ueno (52:47)

You know, can you see thermal bridging with infrared cameras? Sometimes yes, sometimes no. Like if you're walking around the outside of a building, honestly, if it's during the day, the solar gain of the sun hitting the outside will overwhelm anything that you're trying to see on the outside. So pretty much next to pointless. So if you're trying to do a outward air leakage test or look for thermal bridging on the outside, middle of the night or the morning before the sun comes up, those are pretty much your only

 

Jess Kismet (53:06)

Mm-hmm.

 

Kohta Ueno (53:17)

options unless it's thoroughly cold and thoroughly overcast, for instance.

 

Jess Kismet (53:17)

Mm-hmm.

 

Sometimes when I

 

go to do inspections or blower door tests and we're using thermal imaging as a diagnostic tool, I'll ask the clients to put their, if it's cold outside, I'll say could you put your heater on inside or if it's warm outside, I'll say put your air conditioner on to just cool down some surfaces so we can see what's coming through.

 

Kohta Ueno (53:38)

you can. I've asked clients to do the same kind of things.

 

Jess Kismet (53:41)

Mm-hmm. Are you cut out there for a little bit, Krota? What did you just say? Sorry?

 

Kohta Ueno (53:45)

yeah, like I completely agree. And I've asked clients to do the same thing of bumping their thermostat up or down to give me that delta T temperature difference inside to outside.

 

Jess Kismet (53:52)

Yeah.

 

Yeah, yeah, yeah, it's also something I recommend that the building companies and site supervisors that we work with, I say just get a cheap thermal camera because you can easily mean insulation is a good one. You don't have to have you can have less of a temperature difference inside to outside when it comes to insulation, particularly in the roof, because that's very temperature sensitive. And it's a really good tool to, you know, keeping the keeping the trades accountable to making sure that the insulation has been installed correctly. So

 

I like the thermal camera too.

 

Kohta Ueno (54:23)

Absolutely.

 

I was walking in Attic recently where all the team had signed off thinking things were done and I'm seeing all of these Attic bats in the floor completely pulled back, just leaving bare ceiling underneath them. But that was nowhere near as convincing as walking into a room underneath that and showing like, look at the patchwork quilt of all of these cold squares that I'm seeing in the ceiling.

 

Jess Kismet (54:39)

Mm-hmm.

 

Mm.

 

Kohta Ueno (54:51)

that you paid for leaving your building.

 

Jess Kismet (54:54)

Yeah, yeah, there's

 

memes going around the internet with like, there's bags of insulation sitting up in the ceiling. Like, un-unopened bags of insulation. There's insulation in the ceiling! It's up there!

 

Kohta Ueno (55:07)

One of my colleagues have said, like, you might as well blow your insulation out into the parking lot rather than try to use it this way.

 

Jess Kismet (55:08)

Yeah.

 

Alright, so beer and building science. have yourself and your colleagues have started this beer and building science forum where you get on the internet and you talk about building science over a beer. We have actually created one in Australia. It's a group called the mindful builder in Melbourne. And yeah, we kind of copied you after actually Brad from Sanford build Co. Shout out if you're listening Brad. He

 

Kohta Ueno (55:26)

Fantastic.

 

Jess Kismet (55:35)

You met him here. think he you might have met him. I think he was at the symposium last year. Yeah, loved it. Came back, raved about it. Couldn't say enough good things about you specifically. He loved your talk about different tools. So this is why I'm asking this question actually about all the different tools you use and how to do it. Concrete testing and all that sort of thing. So yeah, we started our own once a month. We catch up and a bunch of us talk about different.

 

Kohta Ueno (55:39)

Okay.

 

Jess Kismet (55:59)

different topics. And what we find like, we share so much information amongst each other, trying to reduce the silos that we all work in. How effective do you think that your forum has been in doing this? And what kind of people attend? Is it mostly builders, mostly architects, mostly like who goes and how successfully is this information getting out there?

 

Kohta Ueno (56:20)

You're talking specifically about the Westford Symposium Building Science Summer Camp or?

 

Jess Kismet (56:25)

I'm talking about the beer and building

 

science. Yeah, it's a casual chat.

 

Kohta Ueno (56:27)

Oh, building science and beer. like, I definitely want

 

to make sure credit is where it's due. The full buildings, you know, I am a contributor to occasional episodes of BS and beer, but there's the solid team of, know, Travis, Emily, Mike, Dan, the whole bunch that are the force that keep that moving forward. know, hats off to them for bringing on so many great guests, putting out such great content, recording it on YouTube, keeping it for,

 

Jess Kismet (56:40)

Mm-hmm.

 

Fantastic.

 

Kohta Ueno (56:55)

you know, for folks to hear. you know, like it's on my to-do list to listen to the episode with my friend and colleague, Henri Fennell, you know, the rock star of spray foam to make sure I get his little nuggets of wisdom, for instance. But your question was ultimately coming back to how successful is it as a format to keep people out of their. Yeah, yeah.

 

Jess Kismet (57:14)

Yeah.

 

Kohta Ueno (57:16)

Building construction in general is a sadly siloed state of affairs in many, at many times in terms of the various trades talking to each other and then coming together as a cohesive whole.

 

That big picture problem, I don't know if there's a great answer along those lines. You know, we talk as much as we want to about the building as a system, but until you can get an electrician to seal the holes that he's punching through the air barrier, it's going to be an uphill struggle for sure. The BS and beer guys have been doing a fantastic job of disseminating information, absolutely getting it out there. But

 

You know, it's a bigger problem than them to break down silos, I think. But, you know, the thing is, know, high-performance architects and high-performance builders do mesh together well, absolutely. And they are communicating relatively consistently. It's whether or not the spread to the wider building industry that I think is going to be the challenge. I don't have a great answer offhand.

 

Jess Kismet (57:59)

then.

 

Mmm.

 

Yeah, yeah, it's, I've often said that the problem, I mean, maybe this is applies in, in all more industries than just the building industry, but it's often occurred to me that the solutions are not at a regulatory level. They're at there between there between those of us who get together and talk at places like the symposium or conferences and beer and building science and podcasts. And, you know, it's up to.

 

we come up with better ways to do things. And I like being part of that group, know. Yeah, you know, people like yourself and, know, Joe's website that you contribute to a lot, all of the presentations on there, the Build Show YouTube channel, you know, all of the resources.

 

Kohta Ueno (58:56)

Absolutely.

 

Absolutely.

 

Jess Kismet (59:11)

That is where all of the good learning happens. The regulations are usually pitifully inadequate.

 

Kohta Ueno (59:17)

The regulations are probably multiple steps behind where the knowledge, the cutting edge of knowledge in the field is. And also just another data point is I've dealt with cases where I am dealing with techniques I have used for decades and going to another geographic location and a builder says, you know, I've never heard of it. And that kind of brings up that famous quote that the future is here. It's just not evenly distributed.

 

Jess Kismet (59:25)

Mmm.

 

Kohta Ueno (59:46)

is the

 

Jess Kismet (59:47)

Yeah, yeah, yeah, for sure.

 

All right, so let's talk about where this industry is going. You've been around, you know, you're part of the origin story at building science school. You were sort of around when building science kind of started to take off in America. You've seen a lot of change, probably created a lot of change. Where do you think...

 

Kohta Ueno (59:53)

Yeah.

 

You've seen a lot of change, probably created a lot of change. The way

 

we think of it is that going up the four minutes, about a billion times.

 

Jess Kismet (1:00:08)

things are going in terms of climate, carbon, resiliency, electricity

 

versus gas, all of these key topics.

 

Kohta Ueno (1:00:14)

Yeah, so I am you know, so the big trends that are going around in North America possibly small, know smaller and only in pockets right now are Electrification and decarbonization of the building materials. Those are absolutely true There are practitioners who are paying attention to that, you know, whether it gets larger traction, you know, like I can easily imagine that in

 

Northern states those things will take off in Texas 20 years from now. No many people will still have not heard of it, frankly Seems quite possible. It's there's a lot of different directions the industry goes in

 

Jess Kismet (1:00:47)

Mm.

 

Kohta Ueno (1:00:53)

in terms of other future trends, like people often push...

 

automation as a big item and I'm going, it might, but whether or not it pays off is another question. Like in big commercial construction, that's the scale at which robotics does start to make sense. Like I saw this fantastic robot that looks kind of like a Roomba where basically you set it down on the slab of your giant office building and it does your entire floor layout from the CAD plans.

 

just by having a printer that is scooting along. And if somebody accidentally kicks it, it... Yeah, it does layout of all the studs, all the partitions, all of the plumbing lines, where everything draws it on the slab. Yeah. I'll leave the link for you sometime. But it was like, that's an use of robotics that makes perfect sense, rather than having guys with chalk lines and laser levels...

 

Jess Kismet (1:01:30)

Mm, it does your...

 

Like draws it on the...

 

wow.

 

Yeah.

 

Yeah

 

Kohta Ueno (1:01:50)

Is it is it three foot three or three foot four? crap. That kind of thing. Like, you can the machine and let them do it. Or for that instance, like if you are sanding an entire 20 foot tall wall of drywall, they have those robots that do that kind of stuff. Whether it makes any sense in a, like a residence, that's...

 

Jess Kismet (1:01:58)

Hmm.

 

Mm-hmm.

 

Kohta Ueno (1:02:12)

That's an up, like, don't know whether it'll, that's adaptable or not. More power to them if they can make that work, but I wonder whether it can. You know, the aerosol-based sealing methods, I don't know if you've seen those around or not.

 

Jess Kismet (1:02:26)

Yeah, yes, yes, I think reclimatization starting to come out with some of those.

 

Kohta Ueno (1:02:30)

Yeah, basically

 

spraying an aerosol into the air, pressurizing your...

 

Jess Kismet (1:02:35)

beg your pardon, no, different.

 

That's different to what I was talking about. The Aero's AeroBerry or AeroSeal? Is that the company? I've seen it. Looks brilliant.

 

Kohta Ueno (1:02:40)

know, aerosol barrier. Yeah.

 

It's a fantastic technology.

 

Jess Kismet (1:02:45)

Mmm.

 

Kohta Ueno (1:02:45)

definitely costs. And there are certain cases where it will work versus won't work. But that seems like a fantastic tool to add to the toolbox. If, you know, just as a for instance, compartmentalizing multifamily buildings where you basically get each unit to the drywall roughed in state, you know, with all your electrical rough in seal all of the big holes, and basically do an entire floor at a time where folks are just moving their rig down unit by

 

Jess Kismet (1:02:47)

Yeah.

 

Mm.

 

Mmm.

 

Kohta Ueno (1:03:14)

unit having economies of scale. That would be incredible if they could get that to work, but I'm not an economist so I don't know how all of these bits and pieces come together.

 

Jess Kismet (1:03:20)

Mm-hmm.

 

Mm Well, I'd be very interested to hear more about this little Roomba that sets out the layout. I will get that link off of you and I'll put it in the show notes for anyone who wants to do a little bit more research into that and some other things we've talked about today as well. I'll put a few resources.

 

Kohta Ueno (1:03:41)

Yeah, absolutely. I'm happy to put, you know, a side note, I'm happy to put some BSC resources on some of the topics we discussed. Yeah.

 

Jess Kismet (1:03:49)

Yeah, that'd be great. That'd be awesome. Okay, last question. I ask everybody the same question. What is the most important

 

thing that you've learned in your career? If you had one piece of advice for the audience, what would that be?

 

Kohta Ueno (1:04:00)

Wow.

 

Yeah, I'm probably echoing many of your other guests who probably say the exact same rote thing, but staying curious, continuing to gain knowledge is pretty fundamental. That's like, like if you're not learning, you're stagnating. Like that's a pretty common sentiment, but it's very true. I know that the bottleneck for getting information into my head is, you know, not the, there's so much great

 

Jess Kismet (1:04:17)

Mm-hmm.

 

Kohta Ueno (1:04:27)

information out there. Podcasts, YouTube videos, web resources, articles, and I cannot keep up frankly, but I try to learn as much as I can. Like I get the issue of Journal of Light Construction or Fine Home Building in the US. The new article pops up on Green Building Advisor. The new video drops from the awesome framers. I try to catch wherever I can, but there's just so much there.

 

Jess Kismet (1:04:30)

Mm-hmm.

 

I know.

 

Kohta Ueno (1:04:55)

and

 

Jess Kismet (1:04:56)

There really is and we're all busy doing

 

our day jobs and raising our families and having a life But there is like when we got a hungry brain, there's so much information to just I just wish I could pour it all in

 

Kohta Ueno (1:05:01)

Exactly.

 

There's not enough time to get into digest all and to pull out in all of that knowledge.

 

Jess Kismet (1:05:12)

No, there isn't, there isn't, which is why I love my drives because I throw on a good podcast and yeah, yeah, so I hope the person listening has done the same thing and has learned something today. Thank you so much, Kohta. It's been a pleasure to talk to you.

 

Kohta Ueno (1:05:24)

Just fantastic talking. Thank you so much for having me.

 

Jess Kismet (1:05:27)

Thanks.