002 - Beyond the Thermostat: What Makes a Home Comfortable?

Ben Hildebrandt: joining me today are Alison Bales and Nate Adams for an excellent conversation around home comfort and how that can apply to residential retrofits. And let's start off by ⁓ getting know both of you a little bit. Alison, if you want to introduce yourself first and tell us your background and yeah, we'll just stick with the background for now. We'll get into the weeds a bit later.

Ben: Thanks for joining us for this episode of Renewing Homes. If this conversation added to your thinking, consider sharing it with others working to improve homes. Better homes through better retrofits. Welcome to Renewing Homes, the Residential Retrofit Podcast. I'm your host, Ben Hildebrandt. This show explores how we improve existing homes through better planning and design, better retrofit work, and better decision making. Better homes through better retrofits? Enjoy the episode. The views and opinions expressed in this podcast are those of the host and guests, and do not necessarily reflect those of any affiliated organizations.

Allison Bailes: Okay, sure. my is physics. I ⁓ got bachelor's in physics and then I was out of school for a while, ⁓ which three years of teaching high school science and some physics. And then I back to grad school, got a PhD in physics ⁓ and ⁓ learned lot that I have forgotten. ⁓ I forgot most what I used to know back then. But the basic principles and especially in graduate school, one of the main things that I learned was learning to ask questions to go deeper and deeper into things. And in 2001, I was teaching at the college level and bought some land, built a house and launched myself into a new career. So it's been a quarter of a century now since that happened. Wow. And since 2008, I've had a company called Energy Vanguard. There are seven of us in the company now. Probably our biggest source of revenue is third party residential HVAC design all over the country and occasionally live in Canada and Mexico. that's what we do. And also I do a lot of writing. I've been writing the Energy Vanguard blog since 2010. I have a book out called, A House Needs to Breathe, or Does It? And the answer is no, it's on page 23.

Ben Hildebrandt: So skip to page 23. But there's lots of good stuff before that in the book, right? I would say really quick, your blog, I've read many posts, really good information and I love your perspective on a lot of different technical topics that you've jumped into in your blog there. So Nate, Nate the house whisperer, why don't you tell us a little bit about yourself?

Allison Bailes: And after this, yep.

Nate Adams: Well, I chuckle it away because here's Allison with his PhD or PhDs. it plural now? ⁓ didn't know. I'm, ⁓ yeah, that's right. ⁓ I'm much more on the auto-didact side, which is self-taught from observing and trying to understand and trying understand what works and what doesn't and hopefully why, ⁓ not to the why.

Allison Bailes: No, no, no, there's no way I ever get to. One is more than enough.

Ben Hildebrandt: you

Nate Adams: and yeah, Allison and I, we've met, it's been a minute. I think it was 2012 or maybe even 2011. I think 2012 we Yeah, yeah, BPI. Yep. ⁓ ⁓ there you go. ⁓ cow. You actually remember. And so I was an installation contractor for a few years from 09 through 13. ⁓ And the better I got at what I did, the less money I made.

Allison Bailes: 12 first time in person, Baltimore.

Nate Adams: And I believe Alison, you're also recovering home performance contractor. And so switched over to something a little bit different that picked up the house whispering nickname. helping ⁓ ⁓ clients with existing homes and really ⁓ complicated, multi-layered that we trying to peel apart and did some pretty projects. that website still up, even though it's The company doesn't exist anymore. It's at energy smart, Ohio.com. You can look at some very detailed case studies kind of later into that in 2017, I wrote the home comfort book and that meant to be a building science on one, if you will. So like Allison is such an excellent communicator and writer. But I did have a struggle when I was learning. There's all of these just kind of random topics that come together and I needed a framework to wrap around them and then I could understand everything else. So I wrote what I wish I'd had in like 05 or 09 when I was first getting rolling in this world. So that's there and actually I'm in the middle of editing my second book right now which is called Common Sense HVAC. So I just set the manuscript to my side as I logged on today.

Ben Hildebrandt: Mm-hmm. Yeah, awesome. That's great. So a lot of great work that both of you are doing. And both have been touching home comfort from similar but also different perspectives as well. So I'm really excited to dive into that conversation. maybe Nate, if you want to start off the conversation with your background ⁓ the book that you wrote several, almost a decade ago now, I guess, and a decade ago now you were probably finalizing it. how

Nate Adams: Yeah, and this is going next year.

Ben Hildebrandt: How would you describe, like what is comfort in the home? And alert, it's more than just that setting on the thermostat and keeping our wives happy with where that's at. So ⁓ how you describe home comfort?

Nate Adams: Well, I'm going to go to Robert Bean and I'm betting Allison will nod along, who taught me about the concept of mean radiant temperature, where it's basically just the average surface temperatures around you. there's kind two pathways you can get there. So Robert is a wet head. So he likes to heat and cool the water. ⁓ Allison I lean more towards the airhead side of things. I'm definitely an airhead. So I to heat and cool with air. Now, what makes radiance what like heat

Ben Hildebrandt: Mm-hmm.

Nate Adams: easier to do that with is like if you have a big old cast iron radio radiator and the heat shuts off, that's still got a couple of gallons of hot water sitting in it. So it takes a while before that cools down the room temperature and it makes houses feel just awesome. And I chuckled the feedback that I got from one client where we pulled out a 70,000 BTU furnace and put it in a two ton heat pump, which turned out to be significantly oversized. Even carefully modeling, we were way off. It was more like 14,000, not 22.

Ben Hildebrandt: Wow.

Nate Adams: we modeled. It was an end unit condo and she kept her temperature a little bit lower so she got a lot of heat from her neighbors, I think is what ended up happening. It like all these little things can matter. But she emailed me shortly after the heat pump started up and said, Nate, I feel like you put a bunch of invisible radiators all over my house. So what that was was the system was running almost all the time and putting a little bit of heat or a little bit of cool in all the time the same way that that radiator

Ben Hildebrandt: You

Nate Adams: do that as well, where it takes a while to cool off. so you can get everything in the house to be really close to the right temperature, and you'll hear Robert about the thermostat, yes ⁓ it's not a but there usually is a number on the thermostat. Because another thing that I found with clients was if they're like 71 feels cold, great try 72. ⁓ And there was a point where they're like, ⁓ yeah the house feels awesome, good leave it there.

Ben Hildebrandt: Mm-hmm. Mm-hmm.

Nate Adams: doesn't cost that much extra to run it another degree or two warmer just run it. Another friend of mine named Robert Brearley defines comfort as when everything in the house is within two to three degrees of what the thermostat says. So and I should say that's Fahrenheit for your Canadian listeners more like one degree Celsius plus or minus but if you can get everything in the house to be similar in temperature the house will feel awesome.

Ben Hildebrandt: Mm-hmm.

Nate Adams: basically requires right size variable speed equipment that can turn down pretty low it is surprising how much of the year ⁓ got very low actual heating and cooling loads, say less than half a ton.

Ben Hildebrandt: Mm-hmm. Yeah, and I think that's an interesting perspective to you talking about having that uniform temperature throughout the home. I can't remember, there's that term for when you've got, you're facing one temperature on one side of the body, but behind you, ⁓ getting maybe even a dozen degrees disparity between the temperature you're feeling and some radiant asymmetry. There we go. Robert will be proud for us.

Allison Bailes: Radiant asymmetry.

Nate Adams: There we

Ben Hildebrandt: And guess to keep Robert proud as well, Allison, do you want to maybe provide a really high level ⁓ of the ASHRAE 55? Because ⁓ it's more than having those uniform temperatures around us, which addresses that mean radiant temperature, but there's other influences as well. And that radiant heating is really... or sorry, that home comfort is really kind of subjective. So what does Ashray Standard 55 address for the factors of comfort?

Allison Bailes: Yeah, that's a great question. So ASHRAE Standard 55 is the standard on thermal comfort. so let's just back up a little bit. So we've just been using the word comfort by itself, but people use the word comfort for different things. Some people say if the house smells good, that makes it comfortable. That's a different part of indoor environmental quality, IEQ. And what I think you brought us on today to talk about was thermal comfort.

Ben Hildebrandt: Mm-mm. Mm-hmm.

Allison Bailes: which is how are we interacting with our surroundings thermally? before get into the standard, mean, there's the three ways that we transfer heat, conduction, convection, and radiation. ⁓ we, a of times think about conduction and convection before radiation, but radiation is probably the biggest in how we interact with our environment because ⁓ our bodies are engines. We are constantly, ⁓

Ben Hildebrandt: Mm-hmm.

Allison Bailes: metabolizing food and turning it into energy and we have excess heat, we are constantly giving off heat. Even in the winter, middle of winter, we have to give off heat. We want to moderate how quickly we would give it off so we don't lose too much, but we have to give off heat. So We're interacting thermally with our environment. Radiation is a huge part of it. So what Nate mentioned there, the mean radiant temperature is huge. It's more important than the air temperature. And Robert Bean, again, is always talking about this. Don't focus just on what the air temperature is. There's way more to it. And I'll give you the five other factors from the standard in a second. before we get there, there's one more thing we have to talk about. And that is in standard, they define thermal comfort. It's not a number. It's not a certain Actually, ⁓ a ⁓ state of mind. ⁓ This in the definition of thermal comfort. It is a state of mind that when ⁓ ⁓ of express satisfaction with their surroundings, their thermal surroundings. And ⁓ so you're feeling too hot, too cold, too humid, and ⁓ you thermally

Ben Hildebrandt: Mm-hmm.

Allison Bailes: And the factors, so actually the six main factors that lead to that feeling of satisfaction your state of mind, dry temperature or just the air temperature, which is what most people focus on. ⁓ And there's the humidity because we ⁓ heat with environment through evaporative cooling sometimes. And if the humidity is too high, then our evaporative cooling doesn't work as well. And so we feel that. And then ⁓ radiant temperature, of course, and And then two factors that we haven't talked about yet. ⁓ Metabolic rate. So house can be perfect temperature and, you ⁓ know, the radiant temperature everything. ⁓ But you might still uncomfortable ⁓ because you've just been out for an hour on the stationary bike or the treadmill and you want it cooler. So. Or you might be wearing clothes for your 28 Fahrenheit outdoor temperature there in Calgary. And it's 72 in the house. insulation, metabolic rate, air ⁓ humidity, radiant temperature, and I think I did not mention ⁓ air speed, the drafts that you feel in wintertime or the cool breeze that you feel in summertime. So all six of those things are. ⁓

Ben Hildebrandt: Mm-hmm.

Allison Bailes: really important, not just air temperature.

Ben Hildebrandt: Yeah, and I think that's really important to understand the disparity and maybe we should have brought Robert in on this conversation too. Maybe that's a part two in the future will bring him in for his perspective as well. But I think one of the aspects too, when we look at that thermal comfort for homes, it's not, okay, here's the set point and you're always going to be comfortable. It's going to vary a lot. I look at my house, I have a 1981 level split in Northeast Calgary, not really improved. any at all. So I've got probably about R9, R10 effective walls. Our furnace set point, we adjusted a lot in the fall. If it's a colder day outside, if it's going to be 32 Fahrenheit or zero Celsius or several degrees colder, or if it's a dozen degrees warmer the next day, like that same set point, the 20 degrees Celsius, 72 Fahrenheit inside doesn't maintain comfort. And that's mainly because of those poor walls the radiant temperatures.

Nate Adams: How much of a size of the equipment and runtime though? Just going to throw that in there.

Ben Hildebrandt: I would say my furnace is oversized. We have a newer one. It's high efficiency. I love the Ecobee thermostat I installed because it allows me to see here's the stage one, stage two for the burner. And when we had that cold snap a few years ago in Calgary where we got down to minus 35 Celsius, so probably like minus 25 or so Fahrenheit, I can't remember the exact conversion. On those coldest days, ⁓

Nate Adams: hold.

Allison Bailes: Now it's just...

Ben Hildebrandt: We're only in stage two for like a half hour in the morning. And the rest was stage, so I was like, okay, this is massively oversized for my home. And then you get into that airspeed in the home with the furnaces running and how does that circulation work.

Nate Adams: So I have a quick story on that, if I may. So what we've ended up doing since moving here to southern West Virginia, the new river of the New River Gorge National Parks, half mile behind my back. So there's a little strip of Boy Scout land and the national park behind me. And we have created all of these really cool themed Airbnbs, but the housing stock here is basically like 600 to 1000 square foot ranches. There's never been much money here. There's a handful of big houses, then just a whole bunch of little ones. And one of the ones we did,

Ben Hildebrandt: Yeah, go ahead.

Nate Adams: I chuckled because we were staying there just polishing things up and sure everything was just so. ⁓ my wife looks at me and says, this is the most comfortable home we own. It's a 1950 ranch with nothing in the walls, about two inches of attic insulation ⁓ the wiring up there is sketchy enough. I'm not insulating it till I totally rewire the house. but has a one and a half ton Daiken fit heat pump that can vary down to four thousand BTUs, thousand BTUs, so like a window unit worth of output. ⁓ And it's also a bit noisy. It doesn't have enough duct work. I left the duct system that it had, which was six six inch ducts, and that's it. It's an experiment because next the game house I did a duct design and everything in just so. But

Ben Hildebrandt: Mm-hmm.

Nate Adams: my wife's comment that that is the most comfortable home we own that has the worst shell of all the homes that we own but the system never shuts off is a key indicator to me and that was something that i've learned over the last couple of years that's really messed with my mind is that well first off shell work at scale i honestly have no idea how to do it and i've been hunting for the path for long long time

Ben Hildebrandt: Mm.

Nate Adams: helping people buy right size variable speed equipment when they replace it that can blunt or even eliminate a ton of comfort complaints something that is very doable at So that's what I've thought about there. But my wife's comment on that, just, I just chuckled. like, do you know what a turd this house is compared to our other places? ⁓ It's awful. The only that's good in that house was, and why we bought it, going to the whispering side.

Ben Hildebrandt: Yeah.

Nate Adams: I joked that when we bought the house, was a river runs through it without Brad Pitt, because there was like three to five gallons a minute of water coming out the basement door, because everything here is on a hill. So while the front of the house is pretty close to ground level, even just by the back of the house, you can walk right in. it just, it freaked everybody out. ⁓ And sellers were like, as is, like, it's your problem. And I'm like, well, I'll figure it out.

Ben Hildebrandt: ⁓ wow.

Nate Adams: And so we did, it was a whole, there was a spring underneath the house and then all of the gutters were draining into the basement, was a lot of what was happening. So had to encapsulate the whole basements. We put Schluter, like the stuff you put underneath tile, the underlayment, and then poured a little bit of concrete on top of that. And those two things totally dried out the basement. So like it's actually safe to store things down there where before it was like a cave.

Ben Hildebrandt: Mm-hmm.

Nate Adams: and a pretty wet cave at that. But anyway, that is the only part of that house that actually has a decent shell. The rest of it's terrible. Only the foundation is actually decent. And despite that, my wife was still like, yeah, this is the most comfortable home we own. So like the oversized furnace, if it's not running a good portion of the time, like I find that my houses in the past have been more uncomfortable when it's moderate. So 40 degrees, you five or 10 Celsius. versus when it's cold enough where the furnace is running all the time and warming everything up.

Ben Hildebrandt: Yeah, and I would say that's what we see in our house too, in colder climate. so we're in climate zone 7A in Calgary here. you are, is it zone four, zone five where you're at?

Nate Adams: I swore when we moved here because there's this little spike that comes down of climate zone five after moving south from Cleveland to try and get a little bit warmer winter. And I look at it like I'm still in five mother. ⁓ But in all fairness, it's four here by the conditions. It really is now.

Ben Hildebrandt: you Yeah. Yeah, yeah, I think those moderate conditions in my experience, it's outside weather impacts a lot more, like a sunny day versus a cloudy day has a huge impact on the inside temperatures and how much your furnaces is where your heating system is working. So I ⁓ find really, really interesting to see all the different factors. I think it goes back to ⁓ the house a system thinking too, like ⁓ we have multiple parameters that impact how someone perceives comfort. I think radiant is one of the biggest ones that radiant temperature we're feeling. Yep. Yep.

Nate Adams: 60 % if memory serves from what Robert talked about. So it's more than half. So if you're only dealing with convection and conduction, you're missing more than half of the equation.

Ben Hildebrandt: Yeah. And when we get to colder climates and we're talking about those existing homes, which have like a R10, R9 effective wall assembly and you get the colder temperatures, that inside surface of that wall is like, I've played around with the thermal camera a weeks ago at my place and we're, I think 14 to 16 degrees on the inside face of that wall on some faces of the house. And so that would be in the sixties Fahrenheit.

Nate Adams: Mm-hmm.

Ben Hildebrandt: I should have brought a conversion table up on the side here.

Allison Bailes: Yeah, that's right about six, 14 to 16 would be right about 60. So it'd be 57 to 61.

Ben Hildebrandt: Yeah. Yeah. So there's, there's a huge impact there and, and, and what we perceive in, in homes. And so I think, I think we've talked to, touched a little bit on, on this, but I saw maybe I'll throw a question to, to Allison, where would, where would you fill in in the conversation thus far in, in, and what are the most common reasons that existing homes are experiencing discomfort? I'll say add thermally onto that. That's kind of the overarching. topic here we can get into the other aspects of comfort another time which I think are very valid as well.

Allison Bailes: Yeah. So, well, in terms of the enclosure, there's some big areas and Nate has seen all this stuff. Anybody who gets out in the houses and knows what they're looking at sees this stuff. Number one, lots of air leakage pathways, huge chases open into the attic or the vented crawl space and all the unsealed penetrations. The top plate. in the attic and there's a little gap between it and the drywall. That's maybe only an eighth to a quarter of an inch, ⁓ it runs for hundreds of feet. So that heads up to a big hole. And with stack effect driving air through it, you get a lot of heat loss and sucking in heat from the bottom. So air leakage is huge. ⁓ one my, probably the most interesting hole I have found in a house is in my wife's house. ⁓

Ben Hildebrandt: Mm-hmm. Mm-hmm.

Allison Bailes: about 15 years ago, it was my second to last contracting job ever. was doing a bunch of work on their house ⁓ I was crawling around the attic when I was first doing the assessment and I saw this very black insulation that had originally been yellow. ⁓ I pulled it aside and there's a big hole. Somebody cut this big hole in the drywall, was probably like three of a square foot. And I down in there and I saw the back of the refrigerator. They had had their kitchen remodeled a few years earlier and the guy or the contractor decided the fridge, ⁓ because was set into a niche in the cabinetry, ⁓ needed be vented to the attic. And that's a huge amount of heat loss in the wintertime. And you're aiding it. ⁓ You ⁓ an stack effect when you throw extra heat from the fridge. So air leakage huge. Another one, know, the uninsulated and poorly insulated areas. ⁓ bonus rooms or some places called frogs, the finished room over the garage. into the attic and look at the walls in that bonus room ⁓ you will see, if lucky, you'll see some fiberglass bats there and you won't any drywall. But if you see the fiberglass bats, that ⁓ number one you there's not an attic side air barrier that should be there. But Most of the time you don't see them all in place because they are falling out almost as soon as the contractor leaves they fall out of those walls. So in the summertime you've got 120, 130 degree air in there. That drywall is very hot. So even with 68 degree air temperature in that room you can be uncomfortable because you're getting blasted with that radiant heat. So that finding something like that that's an easy fix and easy win and all kinds of places in the building enclosure where things like that happen.

Ben Hildebrandt: Mm-hmm.

Allison Bailes: So get the enclosure fixed right. And on the mechanical side, duct leakage can make it very difficult. One of the very first jobs I ever got called in to, know, house to look at, you know, I'm here in the Atlanta area and she said, you know, she was having, she had two systems, one for the main floor, one for the second floor. And the second floor, she said she couldn't get the temperature below about 85 degrees. So I walk up into the attic ⁓ did have my camera. That was before cell phones good cameras and digital cameras were just coming out. I had one, but I didn't have it with me that day. And ⁓ I wish had that picture. ⁓ The air had, it was an upflow ⁓ furnace and conditioner. the, ⁓ so the and coil and return plenum are here. There's a filter. here and then there's a vertical ductboard plenum which fallen over and there's a huge gap between it and the filter. So ⁓ very air from the house was getting pulled into their return. So she was cooling, trying to cool 120, 130 degree air ⁓ and not going to, you're not going to, she was lucky she was getting it to 85. ⁓

Nate Adams: Right? Yeah.

Ben Hildebrandt: Yeah.

Allison Bailes: That means she was pulling some house air because yeah, if it's all 120 degree air, you're not getting that house to 85. So ⁓ another thing. You look for things like that. ⁓ And then on the sizing operation side, variable capacity or multi-stage is the way to go because as Nate said, the vast majority the hours of the year, ⁓ you're in part conditions. The house. ⁓

Ben Hildebrandt: Mm-hmm.

Allison Bailes: The outdoor conditions are not at those design temperatures that you design for when you do manual J. if you have fixed capacity, it's either on or off. So if you go to multi-stage, most of the time, let's say two-stage, most of the time it's going to run in low stage. Occasionally you might need the upper stage. And variable capacity allows you to vary continuously.

Ben Hildebrandt: Mm-hmm.

Allison Bailes: But here's the thing, Adam Muffich from the National Comfort Institute said this better than I have. I've been saying basically the same thing, but in different words, ⁓ is incredible. said, most expensive fixed capacity system you can buy is an oversized mini split or oversized variable capacity system, ⁓ because your is here. So this minimum capacity is here. But if your load is down here and your maximum load is here and your minimum capacity is here, then they don't overlap at all. So your variable capacity system that you pay extra money for is now just acting like a fixed capacity system, but it is always bottomed out. 100 % of the time it's running, it's bottomed out because you never get enough load to crank that thing up. So you've paid extra money for no benefit. so many people

Ben Hildebrandt: Mm-hmm. Mm-hmm.

Nate Adams: I fully agree.

Allison Bailes: Yeah, so many people say you can't oversize a mini split. You can't oversize variable capacity. That is total BS and not the good kind.

Ben Hildebrandt: And I think that's really, I think that's really a nail on the head moment too for some of the issues. Like across Canada, we've had programs that have subsidized heat pump installations across the country. a ⁓ those have been air source heat pumps. And when we look at having a good effective cold climate heat pump, it really goes to having it sized right, not just hitting that peak heating load, ⁓ But I think the shoulder seasons are really key as well. that ⁓ variable range of that heat pump system is outside of ⁓ what going to need in the shoulder seasons, then that's not going to dial in very well. And I've heard of contractors ⁓ that they're getting a whole truckload of the exact same size of heat pump. And whenever someone requests a heat pump installation, they just roll the next unit off, put it in the house. ⁓ That's not how it should go. We need to have these done proper calculations and it's not just running a manual J or a CSA F-280 in Canada, but it's taking that report and going through the numbers and looking at how that system really connects and how it's going to operate in the home.

Allison Bailes: Yeah, and on the calculation side, I'm sure you're aware of this. I don't know how F280 compares, but Manual J from the Air Conditioning Contractors of America, heating loads a lot. ⁓ done a lot of them. ⁓ just wrote about this last week or the week before ⁓ one our clients in Savannah. ⁓ had BTU per hour furnace. That's the output, not the input. 89,000 BTU per hour.

Ben Hildebrandt: Mm-hmm.

Allison Bailes: in Savannah, 2600 square foot house, way oversized. mean, you I see the look of shock on your face. Anybody knows, you know, sizing and climate and stuff like that knows that's that's way oversized. ⁓ We a load calculation. The load calculation came in at 60,000 BTUs per hour. We did runtime ⁓ measurements the furnace, not this ⁓ winter, but winter. And based on runtime, looked like it needed 46,000.

Ben Hildebrandt: you Mm-hmm.

Allison Bailes: So she put in a heat pump, two-stage heat pump. The upper stage is 37,000 BTU per hour and the lower stage is 24,000 BTU per hour. This winter we got some runtime data on that. It runs almost always in low stage, 24,000 BTUs per hour. So manual J says 60,000 BTUs per hour. We're measuring it. It's more like 30,000 when you factor in some of the upper stage. So manual J in this case is about times too large. this not just ⁓ in climates like where we are, this is Savannah, ⁓ contractors cold climates and Nate can ⁓ affirm as well. ⁓ And contractor who does lot of hydronic stuff and boilers in New York ⁓ said, same thing with boilers, they're oversized. Go to New York City and look at all the open windows. ⁓

Ben Hildebrandt: Mm-hmm.

Nate Adams: Right. I mean, to that point, sorry, it's like I started talking about sizing with runtime and past energy use. I gave a presentation to Cleveland ACCA Group in 2016. So 10 years ago, I was noticing that, the calcs were way, off. My base assumption, which isn't always correct, but it's my first assumption that I go and try and verify is ⁓ manual J I get for heating, I'm going to cut it in half.

Ben Hildebrandt: Yeah, and I think...

Nate Adams: Is that always correct? No, but it's closer way more than you would think. mean, the example Alison just gave was exactly that. 60,000 man J, 30 actual. the that when get into the colder climates, it oftentimes will oversize even more for heating and air leakage matters But you can take past energy use. actually just built a little calculator. where it actually works in Canada. Well, it wasn't until last night when a ⁓ friend of mine said, hey, this isn't working. So I wouldn't figure it out what it was. But if you just put in annual gas usage, it'll give you an estimate of what the load calc is. And now is that dead on? No. But how I view it is sizing the energy use is the bottom end of the spectrum and sizing the manual J for heating is the high side. it's a ⁓ house, you can probably size really close to energy.

Ben Hildebrandt: You

Nate Adams: And if it's not, you probably want to be somewhere in the middle. generally what I find. But yes, can man, can you oversize! So quick story on that. had one client who had just bought just a really nice system. was a ⁓ five carrier air conditioner that was four tons on top of a hundred thousand BTU furnace. And the house would not dehumidify because it was too stinking big. So we had to add a ventilating dehumidifier to the place to make it work. If that had been a three ton heat pump, his house would have been far more comfortable. The house was really uncomfortable too. And it's a 3000 square foot, early eighties build in the Cleveland area. But he bought the wrong piece of equipment. And the thing that really sucks about that is what is the trade in for an existing piece of HVAC? It's zero. In fact, it's less than zero because you have to pay a little bit just to get it pulled out. It has no value whatsoever. So if you screw up in your equipment choice, There is no trade in value. It's not like, ⁓ I bought a pickup truck. really need a At least you can get your trade in for the truck ⁓ for ⁓ now. So choosing correctly is critical. ⁓ my general rule is, and of why like hybrids, because hybrids make it so that the homeowner the contractor are comfortable. Like they have ⁓ the guts they feel like they need. But if you size it home to cooling and stack that on top of a

Ben Hildebrandt: Mm-hmm. Mm-hmm.

Nate Adams: furnace, will probably cover somewhere between 60 and 90 percent of heat load, depending on your climate.

Ben Hildebrandt: cool. ⁓ and I think that's a very valid point of making sure we get the systems right. And it's not, I would say it's when we're looking at like retrofitting a home to hit net zero levels of performance over time and replacing systems as they age out, putting a new system in isn't the end of the world because we're looking at 15, 20 years and we get to try again. But we are locking that in for 15 to 20 years. On that sizing based past use, I'm remembering a conversation Reed was having on his ⁓ better HVAC podcast a couple years back ⁓ they were using and I think this is a possibility for many homes out there potentially ⁓ people have a smart thermostat installed that is doing some sort of logging of use to be able to if HVAC designer installer is able to get into that data and evaluate and confirm like here's how ⁓ how this system is working, then you could dial in and get perfect. The other thing too though, recognizing the occupant habits as well on how they live. And are ⁓ dialing in that HVAC system just for the current occupants of a home? And is that gonna work with a future occupant load in that home? If you're going from a couple of two in a home to then you have a family of six or ⁓ vice that heat load is gonna be very different. I wanted to circle back to one of the comments that Allison made about the ducting and duct leakage. And I just wanted to point out that we have varying across North America and some areas of Canada and a lot in ⁓ the where we have slab on grade homes or homes without basements quite often will have not just ducting but maybe the heating or cooling ⁓ units up in the attic, which can be unconditioned and in those cases that ducting, that air leakage or out of that ducting in that system can create massive issues both on the temperature and comfort and humidity side. ⁓ I was just kind of curious if we have a ⁓ and cooling system that's totally on all the ducting everything is totally within the envelope, is leakage as much of a concern then if that air leakage is just going within the envelope?

Allison Bailes: no, no, ⁓ leakage is a much bigger problem if the ducts are outside the building enclosure. ⁓ If got them in an attic or a vented, unconditioned crawl space or worse in a garage, garage is worse because indoor air quality issues, mainly because ⁓ you may the duct in a garage can cause the house to depressurize and drive. pollutants into the house, it could suck in pollutants directly and return leaks and send them into the house. yeah, duct leakage and unconditioned space is way worse than duct leakage inside the enclosure. ⁓ I almost all our jobs have ducts inside enclosure. ⁓ And ⁓ that's ⁓ all ducts be. In a cooling climate, if you're in a hot climate, ⁓ hot, humid, or dry, you are going to lose probably 20 to 30 percent of the energy that you put into cooling to, you know, just not duct leakage, but just conductive losses just because they're in the attic. Even with airtight ducts, you're going to have a huge loss just from conduction through that duct because we put R-8 insulation on ducts in 120 degree attic with 55 degree air in them. Huge delta T there.

Ben Hildebrandt: You

Nate Adams: And not much air value, yeah. So yeah, I feel like a bit of a heretic for my usual position, which is basically climate zones five and up. I'm not crazy worried about duct leakage because the systems are predominantly inside the envelope, unless you're just not getting enough actual air to the rooms where it needs to go.

Allison Bailes: Yep.

Ben Hildebrandt: Mm-hmm.

Nate Adams: And you can also freeze out basements with the leakage. So like I routinely see that happening where you walk into the basement and it's much colder than it is upstairs. And that is, you know, one of the main causes there, but wherever, yes, you are in a Southern climate, because it basically, once you get into climate zone one through four, you really consistently see duct systems in the attic or the crawl space of the garage. And at that point, you better deal with it. good part, ⁓ oftentimes, especially in older homes, those ducts are fairly accessible in the attic and duct, which is primarily what gets used, ⁓ at it mostly just leaks at each end. So it's not like hard duct, which has a whole bunch of little tiny leakage points ⁓ where goes out.

Ben Hildebrandt: Mm-hmm. Mm-hmm.

Nate Adams: So they're relatively easy to seal those. You seal the ends of the flex and then where it comes through the ceiling at the boot. And that can make a massive difference for not a lot of time or money. But then if you get what Alison talked about before, where like one part of the ⁓ had fallen over, like ⁓ a big issue. Or if an animal chews through a piece of flex, that's a real issue. ⁓ the flex gets scrunched from the cable guy coming through there and stepping on it too hardcore and actually crushing it. ⁓

Ben Hildebrandt: you

Nate Adams: There's a whole lot of different issues that can happen, but in general, for colder climate systems, I'm not a... ⁓ we'll just talk about priorities. I'd rather size the equipment and get a bigger filter and bigger ⁓ return supply plenums. If I out of money, I'm not going to do Mastic on the joints. They run out budget. Down south, it...

Ben Hildebrandt: Mm.

Nate Adams: It's like a must-have. It's one of the first things like if I had to give up on Equipment quality I would do that versus duct ceiling so it depends where you are

Allison Bailes: Well, how much does a bucket of mastic cost up there? ⁓ not very much down here.

Nate Adams: Well, say it's a thousand bucks extra. If you've got a thousand bucks in the budget, I would rather go from a one-inch filter to a four-inch media a bigger return plenum than hit the leaks. Plus, you also have keep an eye on what your static pressure is, and that may drive further than you want to go, but that should get measured. a whole other story of

Ben Hildebrandt: you

Nate Adams: how often it actually is, but at least with the TruFlow Grid that's easy now.

Ben Hildebrandt: Yeah, and we're talking all ducts inside the envelope in this case of sealing. ⁓

Nate Adams: Yes, yes. So for that, I'm less worried, but it's, it's a constant battle of what do we prioritize? mean, like say you got 15 grand for a system, what are you going to do? Um, and that is the, give and take. I, and I think that's where, uh, like I've found myself at odds, uh, sometimes is I'm, I'm trying to think what can we do for the vast majority of homeowners, not just a few percent. And they're extremely different arguments.

Ben Hildebrandt: Mm-hmm.

Nate Adams: but we're not necessarily talking apples to apples in what we're suggesting. So I'm usually trying to figure out how do we actually make good work, good systems normal instead of the exception. that's a, it's just a challenge and it's a ⁓ in opinion and a difference in approach that leads to differences in opinion. ⁓ and that's okay.

Ben Hildebrandt: Yeah. Yeah. And when we talk about achieving thermal comfort in existing homes, is there much that either of you have seen in your projects that can be said for just properly balancing a system provide that comfort? And that came to mind as we're talking about ⁓ leakage. You're not getting the air where it needs to go ⁓ much. I look at a lot of the homes that go in in Canada, specifically the large production builders where the they're not getting calculations for the sizing, let that duct layout as well. They're throwing a supply register each room and we need two in this living room because we've got large windows and that's the amount of thought that's going to it. But how much of an impact can be made just by looking at that balancing and potentially adding zones to a forced system? know that if we're looking at zoning an existing system, there's other components and a lot of work that can come into that. But what are your thoughts on that?

Allison Bailes: I would say forget trying to balance an existing duct system because that duct system probably was never designed or designed. And if it was designed, it wasn't designed properly. if you want good airflow in the house, rip out the duct system and start over. That would be the way to go. But there are some things you can do to get better airflow because one thing that I have seen over and over

Ben Hildebrandt: you

Allison Bailes: in houses and unconditioned attics and vented crawl spaces disconnected ducts. you know, where, you know, a duct comes off of a boot. ⁓ room, all of a sudden, you know, ⁓ room didn't used to be this cold and winter. Why is it so cold in here now? Well, you get under the house and you see the duct fell off of the boot. And so the crawl space underneath the floor is a little bit warmer, ⁓ that room is not warm enough. So ⁓ ducts would be definitely something to look for an existing home. if you've got a big disparity and things have changed.

Ben Hildebrandt: Mm-hmm. Yeah.

Nate Adams: Yep. I would agree with that. Now, ⁓ different ways look at this though. For zoning, I actually generally don't like zoning at all because it really needs to be like three equal size zones and you need to make sure you actually have enough return to support that. ⁓ You're going to drive the static pressure of the system through the moon when only one's calling. ⁓ So zone system that I've come into, I have disconnected ⁓ and comfort. Hasn't been a huge number, but it's been some.

Ben Hildebrandt: Mm-hmm. Mm-hmm.

Nate Adams: and then I've done two zoning systems myself and both of them were challenging they're all two zone systems. like zoning in general I largely take off the table but other piece is ⁓ again playing with the HVAC 2.0 program which is mainly a sales process and not part of it anymore but

Ben Hildebrandt: Mm-mm.

Nate Adams: in dealing with bunch of HVAC contractors in just normal houses, I am shocked how many houses can be substantially fixed by right-sized variable speed equipment. And like I'm aggressive on downsizing and I get into fights over this all the time. But like in the 30,000 BTU house that you were mentioning, Allison, I'd probably do a two-ton with resistance on that if I actually trusted my load. And that would cover a huge swath of the year. as far as running all the time and at least if you have some air going through some heating cooling going through all the time and you have the system the air handler running whenever that's not happening you're going to mix the house ⁓ you can take five degree temperature differences and make them two or three is it perfect no

Ben Hildebrandt: Mm-hmm.

Nate Adams: But realistically, is it? install, say, call it 10 million pieces of HVAC, residential HVAC in the US every year ⁓ furnaces, air conditioners, and heat pumps. How can we actually affect a substantial number of those? And significant renovations aren't going to happen at scale. So what can we do that's reasonable in the middle ⁓ and hopefully help lot of those people in sizing aggressively and ⁓ putting in filters?

Ben Hildebrandt: Mm-hmm.

Nate Adams: filters like Allison you'd appreciate this one of my systems is one and a half tons I have 20 by 25 on it the filter drop is 0.03 with a MIRV 13 that's nothing absolutely nothing the static on that whole system is 0.13 at 600 CFM its design flow and so those are things we can do right sized variable speed big filter maybe a fresh air duct things like that

Ben Hildebrandt: Mm-hmm.

Nate Adams: are things that can be done more at scale. If you do have the budget, yeah, it may get into duct replacement. And then in the south, where you've got lots of flex duct, where things are easier to do, that becomes more on the table as well. In the north, where you've got hard ducts running through walls, you ain't changing those.

Ben Hildebrandt: Yeah, I think in that case we're looking at zoning, adding zoning or decommissioning zoning to your point, guess part of the equation too. If we can look at addressing the shell of the building, if it's due for a cladding replacement and they add some insulation, reduce the heat loss there, reducing the overall heating load in the building and that can help balance things out on its own by reducing that disparity a bit.

Nate Adams: Shell's next.

Allison Bailes: Let me jump in on the zoning question well because also same opinion about that. Zoning systems are difficult. ⁓ Contractors who them don't really understand zoning very well and they are usually more trouble they're we sometimes in our design we have clients who insist on them and so we have to do it. ⁓ the way we prefer to zoning is with equipment, not with dampers. Because if you have a separate piece of equipment for every zone, then it's a lot easier. another thing I want to mention about zoning, one of the worst things you can do with the zone system is put in a fixed capacity piece of equipment and a bypass duct. will kill the efficiency on that system. You may freeze the coil in summertime. You may crack a heat exchanger if it's a furnace ⁓ ⁓

Nate Adams: There you go.

Ben Hildebrandt: Mm-hmm.

Allison Bailes: you're sending conditioned air back into the return side with that bypass duct because you've got too much air for the whole, for the, let's say one zone that's calling. So you're sending air back. So in the summertime, you're, you're colder and colder air through that system. So you're getting a smaller and smaller Delta T and, and, and you're killing the efficiency and possibly freezing the coil. So.

Ben Hildebrandt: Mm-hmm. Yeah, so I guess when we're talking zones, it might be, if we're looking at putting in a whole new system, there might be some homes where like a mini split heat pump system might make sense. And I would say too, like we haven't really got this whole other conversation we had around radiant heat. I'm like, radiant heat, and that's a system where it be easy to zone, but you're talking a lot more for running, ⁓ hydronic lines like PEX piping throughout and what are the different fixtures you're using in the room for your heated tail bar and every zone has a valve on it that is controlled and I look at that it's like each one of those is it's not that they're unreliable they're gonna fail but it's another piece of mechanical equipment that might wear out over time and and require replacement so

Nate Adams: That's a scale thing in my mind. The nice hydronic systems you're usually going to see in multimillion dollar homes. Most HVAC systems are say between 10 and $30,000, give or take. There's a big range there, but like a hydronic system is going to easily be a hundred grand installed. So it's a very different conversation. Not that it's an invalid conversation, but again, my,

Ben Hildebrandt: Mm-hmm. Mm-hmm.

Nate Adams: lens is always in the bell curve where you've got the 68 % of the two main standard deviations. How do we actually get to that 68 % of people? yeah, hydronics are generally not the answer. But they can be really nice. I had a house with it, although man, was the zone valves were really frustrating. So my kitchen was either 60 degrees or 80 degrees. So you were either shivering or you were in your underwear. There was no in the middle.

Ben Hildebrandt: not that fun. ⁓

Nate Adams: No, but a variable speed pump on that system, even having just an old school cast iron boiler, just ⁓ zone valves that actually worked when they were supposed to, and a variable speed pump drastically improved the comfort of that house. it's just... always have system running with a little bit of heat or a little bit of cool as much as you can, which means you need to size as small as you can, even with variable speed, so that you can cover 70, 80, 90 percent of the year with the system actually running and heating and cooling.

Ben Hildebrandt: Yeah. Yeah. Awesome. So I think we've covered quite well kind of the HVAC mechanicals end of things when it comes to thermal comfort in the homes. What are your, as we wrap up, want to get some quick thoughts on the shell or envelope a building. So we have kind of the opaque assemblies, the wall assemblies and attic assemblies and stuff. And then we have the fenestrations, windows and doors. Like where's the effort best put? in a retrofit situation to achieve comfort through improving the shell.

Nate Adams: Allison.

Allison Bailes: start with air sealing. You the house as airtight as you can. And so fall, all the articles and the news stories come out about, OK, get for winter, get out there and caulk your windows and weatherstrip your doors ⁓ and you'll a lot of money and you'll be more comfortable. Well, actually, no, that's not going to help you much. ⁓ any air that you have in those places is bringing straight outdoor air in. Whereas

Ben Hildebrandt: Mm-hmm.

Allison Bailes: The big hole into the attic, place where you're attic air ⁓ that dead squirrel on the top plate, or if you're bringing in ⁓ unconditioned air the crawl space through the bathtub hole, which is a huge hole, ⁓ are ⁓ much more and bringing in way worse air. Yes, the big holes at the top and the bottom stack effect means that those holes are more important. You can have an open window in the inside of the house where the neutral pressure plane is and get pretty much no air movement if you open that window. paying attention to where the holes are. Get ⁓ air leakage done and then, you know, insulate as well as you can the places you have access to. Look for those those knee walls with the insulation falling out in the bonus rooms. See if you can do something about the vaulted ceilings that air is going right up under the fiberglass bats. Just put some blocking at the bottom of them, things like that.

Ben Hildebrandt: Yeah. Awesome.

Nate Adams: come at it from a slightly different angle. Replacement window jobs usually going to be like 15 to 30,000 and it's probably to save you ⁓ single digits the energy front. Might be helpful from the comfort front because windows and mean radiance heavily intertwined. ⁓ But that same 15 to 30,000 put into a good air sealing and insulation job might knock your energy use down 30, 50, 60 percent something along those lines and make the house much more comfortable. Well again, if you have the right size HVAC. Because one thing that I found that one project in particular when I was doing insulation, was the very end when I was doing it, a guy had an addition on the back and of course they'd hacked in the ducts from the main trunk to go back there. And when we insulated the house, we lowered the load of the house

Ben Hildebrandt: Mm-hmm.

Nate Adams: and his addition got colder because we made the system even more oversized than it was before.

Ben Hildebrandt: Wow, that's interesting. And that might go a little bit towards thermostat as well to get that. ⁓ just all size? Yeah.

Nate Adams: Now it's just, that's all sizing. That's all sizing. Yeah. Yeah. Cause the system just isn't running enough. Um, so say it was running 40 % on a cold day. Now it's running 30. And because that addition is exposed to the outdoors, basically on five sides, um, uh, it just doesn't heat well. Um, so that was the challenge. Yeah. So the, like I said, it'd been beaten into my head from multiple directions. The last five, eight years of how important.

Ben Hildebrandt: Mm-hmm. Mm-hmm. It's not getting enough there.

Nate Adams: variable speed right sized equipment is for step one, but then you also want to size it to where you're going. So like if you're planning to do shell retrofits, you want to have an idea of what your load is going to be and size towards that. yeah, it's talk about multifactorial. ⁓ ⁓

Ben Hildebrandt: Mm-hmm. as a system. ⁓ And I think one too, like in Canada, we have the EnerGuide for Homes rating system, which ⁓ is And I haven't gone into the home energy rating score like the HERS system in the United but in Canada with the EnerGuide rating system, you get a report out of there and they've done evaluation of your home estimating the performance of different assemblies. They do a blower door test to confirm your air tightness. And then that report, you can kind of target and see where your key loads are and where the big areas are for improvement. And I would anticipate that could help inform targets a bit for comfort as well. And on the window side, think it's particularly like windows in a lot of homes. There's not tons and tons of windows, so it's not going to make that huge of a difference from energy savings. But if you have a living room and you're like sitting where you have large windows that are older and inefficient. that can have a really good impact on comfort potentially in homes as well.

Allison Bailes: Yeah, but there are other things you can do besides replacing the windows. There's something called Indo windows, which is a piece that's ⁓ with an acrylic, clear acrylic. ⁓ you measure the windows or the contractor measures the windows ⁓ they make a tight fit in the opening. So it's like having an interior storm window. yeah, ⁓ I-N-D-O-W, windows. ⁓

Ben Hildebrandt: Interesting.

Nate Adams: Yep. Window with no W. and that's also where just the old school plastic that you, ⁓ shrink fit with a hairdryer could help a great deal too. So yeah, it's. Yeah, I mean, it's all a budget question. Like, what do you, what do you to work with? And like, ⁓ so I view it as you've got the client goals, ⁓ you have what house needs and you have budget.

Ben Hildebrandt: I grew up with that stuff.

Allison Bailes: Yeah

Ben Hildebrandt: Mm-hmm. Mm-hmm.

Nate Adams: and want to try and find a way to make all three of those in a Venn diagram cross each other. some of the answers may not be great. Like I did energy audits for a couple of people and I left them ⁓ guys, you need to do window units and space heaters because you've like a $2,000 budget ⁓ and nothing that can be done within reason within that budget. ⁓ So you just need to add heating and cooling to those specific spaces. And that's not...

Ben Hildebrandt: Yep. 100%. Mm-hmm. Yeah.

Nate Adams: a satisfying conclusion, but it's a real one. And so you always have to be thinking about what is it worth to fix this?

Ben Hildebrandt: Yeah, awesome. So as we, I guess, I want to get your, your thoughts on ⁓ item here, which we may have touched on earlier, but just ⁓ clarify, what would each of you say is the biggest misunderstanding you're seeing in regards to home comfort, ⁓ home comfort in the industry right now?

Allison Bailes: I would, ⁓ say what Robert Bean says, you know, it's, way more than just air temperature. And I mean, Robert Bean, if you if you follow him at all on online or anywhere and you ever hear him speak, he always hammers on this. Stop focusing on what the thermostat says. Thermal comfort is a lot more than that. And it's even more than mean radiant temperature, which is important. It's more than half of ⁓ heat transfer happening. But

Ben Hildebrandt: Mm-hmm. ⁓ yeah. No.

Allison Bailes: It's also humidity and airspeed and what we're wearing and what we've been doing. you've got to pay attention to the big picture. There's a lot more to it than just one factor. ⁓

Ben Hildebrandt: you Yeah. Nate, would you have anything to add?

Nate Adams: I'll come in a different way. One way air conditioners are stupid. I mean the, it's a hundred or 200 bucks parts difference between them and at the wholesale level, $300, $800 difference, usually between the same model air conditioner and heat pump. and even if you just run a single stage heat pump, which is not my preference, but like that makes that gives you two stage heat if it's with a furnace and that make your house significantly more comfortable.

Ben Hildebrandt: Mm-hmm.

Nate Adams: the same, oftentimes less, because the COP's are so high at warmer temperatures where that would be running anyway. Basically, air conditioners are stupid. Pass it on. ⁓ Get a two-way air conditioner, which is something I coined a couple years ago, because lot of people like they hear heat pump and like that's a big misconception. ⁓ it only does heating. No, it's an air conditioner that heats too. ⁓ I it's slightly confusing, so let's call them two-way ACs instead. ⁓

Ben Hildebrandt: You Mm-hmm.

Nate Adams: and always, always, always use one of those because it's intellectually stupid to use a one-way air conditioner.

Allison Bailes: Well, it depends. If you're in Miami, Florida, or Brownsville, Texas, got no real heating load. ⁓ in the US, but in the whole world, it's a much bigger number.

Nate Adams: Alright, so you got like 3 million people out of 300 million here.

Ben Hildebrandt: out of a few hundred, ⁓ really.

Nate Adams: But even there, not have the extra hundred bucks in parts in there to have the capability and not have all the supply chain challenges of having two products? Like Vancouver used my idea of AC to heat pump and I actually helped get two Senate bills written in the US on converting all ACs to heat pumps. But Vancouver made a code that whenever an air conditioner is replaced, it needs to be a two way. that's been super smooth to implement and one of the biggest pros of it is that the distributors love getting the floor space back in their warehouses because they were having to keep two SKUs of the same size you have a two-ton AC and a two-ton heat pump now only have a two-ton heat pump so it actually ⁓ made lives ⁓ much complicated for bringing them in and much less space so I think dumb and like hardly any mini splits actually cooling only there's a few but they're almost entirely heat pumps. So why do we even make air conditioners?

Ben Hildebrandt: Yeah. Yeah. Well, I was thinking we had a few winters ago where there's a of people in Texas that would have wished they had a two way AC. So things changing. So ⁓ I one ⁓ question ⁓ if there's contractor or someone in the industry that wants to dive in and home comfort better on the thermal side, should they start?

Nate Adams: We both have good books. Mine is 101. Yeah. You might start with mine because it's 101 and then everything in Allison's will, make a lot more sense at that point. Cause he's 201, 301, 401. So there you go.

Ben Hildebrandt: Yeah.

Allison Bailes: Yeah, either either or both of our books. Yeah.

Ben Hildebrandt: Yep. Well, there's a lot of one-on-one level blog posts that Allison's done as well on Energy Vanguard, I would add as well.

Nate Adams: True true.

Allison Bailes: Yep. Yeah, I would say a lot of my book is also 101, 102 level, I do go beyond that in parts of the book.

Ben Hildebrandt: Yeah. And I would recommend for listeners as well, if you really want to dive in, go to whatever app you're listening to podcasts on and just search Robert Bean and listen to every interview he's been on. And I think any thermal conversation, we can't wrap up without using that phrase Robert has loved and ⁓ pushed so much, for people, good buildings follow." ⁓ When we look at thermal comfort principles, when we're dialing in that HVAC system, when we're improving the shell, we're providing a comfortable environment for the occupants of those homes. But we also get energy efficiency out of it as well. We get the performance metrics. I think that's one of the key things to remember here too. It's not or. It's not comfort or efficiency. We for the comfort and nine times of 10, if not 99 times out of 100, we're getting ⁓ the efficiency out of

Allison Bailes: and the durability and the indoor air quality and the quiet.

Ben Hildebrandt: And the quiet, yeah. And maybe we can super briefly as ⁓ Allison, you mentioned like there's thermal comfort, but then there's the other aspects of comfort too, not to dive into too much, but we have the acoustic visual comfort, smell comfort. I've thought of my teenage son's room when you mentioned that earlier as well.

Nate Adams: cooperation.

Allison Bailes: Yeah, yeah, and or environmental quality is, you know, the bigger of all these things that that we're designing for, you know, Robert Beans, you know, design for people, good buildings will follow. And why I started my book. You know, there's three sections. The first section is start at the end. And then then I go into the building enclosure. Then I go into mechanical system start at the end, because we have make sure that this building, you know, whether it's retrofitting an existing home or building a new one, designing a new one, we want to make sure that the people are comfortable, that they're healthy in the building, that they're not having to pay an exorbitant amount just to maintain the building because of moisture problems that result from poor water management details. ⁓ So this stuff really matters. And so you got to think about, know, ⁓ what we want out of this building? And that's where you start. You start at the end.

Ben Hildebrandt: Mm-hmm. Yeah, and speaking of the end, think that's a perfect way to wrap up the conversation. Thank you both very much for joining me today. I really appreciate your thoughts and ⁓ look forward to more conversations in the future. Thank you.

Allison Bailes: You're welcome.

Nate Adams: Thanks for having us.