Robin Jade Conde

PODCAST: How to prevent ice dams

Snow was heavy in Minnesota last week. Today, we will talk about what causes ice dams, and how to prevent and fix them. 

 

Tessa explains what an ice dam is and how they are formed. She shares that most houses can fix this through proper air sealing and insulating of the attic space. Reuben adds that most people think this can be improved by adding ventilation to the roof but this is different. 

 

They talk about various roof designs and valleys that are prone to ice dams, as well as locations of air penetrations in the roof, bath fans, and how they contribute to the dam formation. Moreover, they discuss air flow and leakage, attic bypasses, and the importance of adequate attic ventilation. Reuben enumerates the types of vents and other heat sources. Tessa highlights that fixing air bypasses can be a very difficult and messy job.

 


TRANSCRIPTION

 

The following is a transcription from an audio recording. Although the transcription is largely accurate, in some cases it may be slightly incomplete or contain minor inaccuracies due to inaudible passages or transcription errors.

 

Reuben Saltzman: Welcome to my house. Welcome to the Structure Talk Podcast, a production of Structure Tech Home Inspections. My name is Reuben Saltzman, I’m your host, alongside building science geek, Tessa Murray. We help home inspectors up their game through education, and we help homeowners to be better stewards of their houses. We’ve been keeping it real on this podcast since 2019, and we are also the number one home inspection podcast in the world, according to my mom. Welcome, Tess. It’s a new year. I think this is our first recording that we’ve actually done this year. Right? 

 

Tessa Murray: It is. This is the first time we’re recording in 2023.

 

RS: Yeah. First time that you’re doing this, not as a Structure Tech employee, but…

 

TM: Yes. Yeah.

 

RS: You are a podcast, I don’t know, co-host and subcontractor for Structure Tech.

 

TM: Yeah, I guess so. You just can’t get rid of me, no. I’m honored to be part of this podcast, and I really enjoy doing this with you, so I’m glad to be here and happy to be alive. I don’t know about you, but 2023 was off to a little bit of a rough start. I contracted the COVID.

 

RS: A case of the COVID.

 

TM: I did, and I think it’s my first time having it. It was really rough. I started feeling symptoms on New Year’s Eve, and I thought, “Oh no, this doesn’t… This isn’t good.” And it had me down for a couple of days, it was pretty rough, like all the symptoms. I sent you the list of symptoms on the…

 

RS: CDC. Yeah.

 

TM: Yeah, CDC’s website, and it was like, “Check, check, check, check. I have it.” So I have just been laying low the last week and sleeping a lot and getting better, day by day, getting better, but you might hear a little congestion, maybe some…

 

RS: Oh, you look great, Tess.

 

[chuckle]

 

TM: So how is your new year starting off, Reuben? 

 

RS: Mine was a little similar to yours. We didn’t do anything crazy. We just, we made a meal at home, we do that HelloFresh a couple of nights a week.

 

TM: Oh nice.

 

RS: And one of the kids made one of those meals, had some of that, and then I got hit with… Like almost the same thing you did, I thought originally, ’cause about a half hour after we ate dinner, I started getting super congested, and I just thought there must have been a bunch of MSG in that meal or something, ’cause I feel super inflamed. And maybe it was some really inflammatory foods and my nose was all congested, I thought, “I think I’m done with this. I’m not eating these meals ever again.” I’m looking at the ingredients more carefully. And well, it turns out I just got a wicked cold, and it came on as soon as I was done eating dinner. And then you told me what you had, and that’s why I was like, “What do you feel? Maybe I should get tested.” You sent me that list and like, “I have all these.” And I’m going, “Nope, nope, nope, nope, nope. Okay, ooh.” And then I thought, “Oh, poor Tess.”

 

[laughter]

 

TM: Well, I tell you, there’s never a good time to get sick, but I’m just glad that I was able to kinda just slow down and rest and just retreat for a while and just disappear from the world, so not everybody can do that. So…

 

RS: Well, we got hit with a lot of snow over the last week or so here in Minnesota, rejoicing. I mean, some really good snowmobiling. I definitely took advantage of that.

 

TM: Yeah. You did. Did you go anywhere special for that or…

 

RS: I didn’t go anywhere. No.

 

TM: You’re just snowmobiling around the neighborhood? 

 

RS: I got… There’s a trailhead that starts just a couple of blocks from my house, so we just go right there, and I could take those trails to anywhere in Minnesota, pretty much. It is a crazy trail system. So…

 

TM: Wow. Oh my gosh.

 

RS: That was something.

 

TM: Is that why you live all the way up in Maple Grove? So that you can…

 

RS: No, that’s… No, I do this because I live all the way up in Maple Grove.

 

[laughter]

 

RS: I can’t live all the way up here and not do something, not do something to take advantage of it.

 

TM: Yeah. Well, that’s… Yeah, so this is a very conducive winter to your hobby of snowmobiling.

 

RS: Oh, for sure. Yeah. Gotta get you up there some time. We’ve been out sledding together before.

 

TM: Yes.

 

RS: You are good at it.

 

TM: Well…

 

RS: You’re no stranger to it.

 

TM: It’s fun. What can I say? I like going fast.

 

RS: You do, you do. Yeah. I love that.

 

TM: Yeah, yeah. Yeah. No, so we’ve had a ton of snow, like you said, and we’ve had some pretty cold weather and we’ve had some warm ups too, and all of it has taken a toll on our little houses here, and a lot of people are suffering from ice dams.

 

RS: Oh my goodness, yes. Tessa, that is the word of the day right now. Man, we’ve gotten a lot of emails lately from potential clients, past clients, friends, saying, “Hey look, I got ice dams, I got water leaking in, what do I do about this? I just had insulation added, and I still have ice dams, help me. What do I do?”

 

TM: Oh man.

 

RS: So I think it’s time for us to revisit that topic and get into some of the specifics about what really causes ice dams and what you need to do to fix them.

 

TM: I think that’s great. Let’s do it. Let’s dive into it. You’ve written blogs on this in the past, I know we’ve talked about it in the past, but it’s almost like every year, we get amnesia. It warms up, we enjoy summer, spring, fall, and then winter hits again, and we’re all like, “Oh shoot. What do we do about this?” So let’s do it. Let’s dive into it.

 

RS: All right, cool. So Tess, for anybody not familiar, what exactly is an ice dam? 

 

TM: Well, an ice dam is a literal dam of ice that forms along the eave of your roof. And usually, you can tell if you have an ice dam just by looking, you can visually see this kind of thick layer of ice forming along the edge of your roof. And some houses will have ice dams kind of no matter what you do, just due to design or due to the sun hitting the roof and melting snow, but most houses, it’s a problem that you can fix through proper air sealing and insulating of an attic space. That blows a lot of people’s minds. There’s a lot of misinformation out there, and a lot of times people will think it’s a matter of adding more ventilation to a roof or doing something like that, but what it is, is it’s basically the heat escaping from your conditioned living space, from your house, gets up into the attic, it warms up the attic, and that heat basically will melt the snow on the roof. And as that snow melts, it will drain down to the edge of the roof, the soffit, the old part of the roof that is overhanging the exterior walls, and it’ll refreeze when it gets to that section of the roof.

 

TM: Because that section of the roof is cold. There’s no heated space underneath it to warm up the roof deck. And so all of that liquid water freezes at the eave, and then you get this literal dam of ice that forms. And the damage that that can really ensue is caused by the liquid water that continues to melt and gets trapped behind that dam of ice. And nobody wants pulling water on their roof, because then that water can get up underneath the shingles and get into your attic and get into your house. So hopefully, that kind of explain it in a nutshell. Is there anything you wanna add to that, Reuben? 

 

RS: Well, Tess, why do people get this idea that ventilation is gonna fix this? Ventilation does play a part, but talk about that a little bit more.

 

TM: Yeah, well, a lot of times people think that if they add ventilation to their attic, it’s going to take care of the removing some of that heat buildup in your attic and the moisture as well that can build up in your attic too. And so I’d say just in the building industry in general, it is one of the biggest misconceptions of the source of ice dams. It’s a problem within our own industry of roofing contractors and other builders not understanding the science of ice dams and thinking that ventilation will fix it.

 

RS: Yes. And Tess, I had such a long exchange with somebody over the last week or two about ventilation, and I don’t think this guy was even in Minnesota, but he was telling me what he did at his house, saying, “Well, I had this type of vent, we changed it over to this type, and then my roofer put in a powered vent, and ever since then, for some reason, it’s even been worse.” And I just kind of went, “Yeah, of course it gets worse.” And he’s like, “Well, and then I blocked off my gable end vents, and I think that made it worse. But I heard you’re supposed to block off gable vents.” And just for anybody who doesn’t know, a gable vent is, let’s say you’ve got a perfect triangle roof, then at the ends of that triangle, those are the gable ends, and sometimes you’ll have vents at those ends.

 

RS: And if you look at an old school diagram, it’ll show that you shouldn’t have gable vents in conjunction with soffit vents, those are the vents at the bottom, end vents, and traditional roof vents, vents at the top. They say that if you put in gable end vents, you’re kinda putting a vent in the middle, and one of those vents is gonna short circuit, where air is gonna come in low and then it’s gonna leave medium instead of flushing all the way out through your attic. And it looks really good on paper. It’s like, “Oh yeah, that makes sense. Okay, you only want very low vents and very high vents.” But this is in a vacuum, this is in a perfect vacuum, where there are no other external forces on a house and Tessa, come on, what changes all of this? 

 

TM: Oh gosh, so many things, but wind, what direction the wind is, how strong it is, is this…

 

RS: Yes.

 

TM: That’s a big one.

 

RS: Five mile an one hour wind will throw everything in that diagram out the window. And it’s all just useless at that point. Just a tiny little bit of wind against the house.

 

TM: Yeah. Attic ventilation is important. We’re not saying that it’s not. And in a perfect world, an attic would have proper intake ventilation and exhaust ventilation. And that air flow would move through the attic space. And the whole reason we have attic ventilation is to try and protect… Well, keep the attic as close to the outside temperature as possible, and also shingle manufacturers require it too for their warranties to be valid. Because if you’ve got, let’s just say you’ve got a black shingle, and you don’t have adequate attic ventilation, the heat, solar heat can build up in that attic and it can shorten the life of the shingles and the attics get really hot, they don’t have proper ventilation, and then the shingles curl and don’t last as long as they’re designed to. So it is important to have ideally proper attic ventilation to keep that attic as close to the outside temperature, but not having adequate attic ventilation does not cause ice dams. That’s not the main problem going on there.

 

RS: Main, yes.

 

TM: We’ve got a bigger problem, and it’s typically, it’s attic bypasses, and all of that warm, conditioned air leaking from your house up into the attic. Through stack effect, that warm air rises, it finds its way through those little cracks and holes in the ceiling, things you wouldn’t even think about, like wiring, little holes of… Through top plates for wiring or for plumbing, for drain pipes, vent pipes that go up through the ceiling, for recessed can lights, for light fixtures, for even just the wall tops themselves, the interior wall tops, all of those things. Chimneys, chimneys are huge bypasses, either wood-burning fireplaces, actually like masonry chimney itself, or if you’ve got a metal B-vent or a metal flue going up through.

 

RS: You’re not talking about that actual material, it’s not the actual chimney, but it’s the space between the chimney and the framing.

 

TM: Yes.

 

RS: It’s where all these chase ways go up through, it’s not having those penetration sealed. So it’s fine to have that stuff going through your attic, you just need to air seal around it and make sure that they don’t have a passageway for air to go up.

 

TM: Definitely, and even things like like bath fans. Now, people might say, “Well, why would you build a house with all these holes in it?” It’s not intentional, of course, and we’ve gotten a lot better, at least here in Minnesota, about knowing about these problematic attic bypasses and sealing them. And in theory, every new construction house that’s built needs to be blower-door tested and meet a certain air leakage requirement. And a lot of times, builders are aware of these and they’re trying to do their best to seal them up. But I’ve seen new construction houses that meet those standards for air leakage, they pass the inspections, but they might still have a few attic bypasses and depending on kind of the volume of the attic space, the adequacy of the ventilation, the location of the attic bypass, you can still suffer the consequences and have problems because of those attic bypasses and their location.

 

TM: And just a short story, there was a new construction house that had a bath fan that hadn’t been air-sealed and that bath fan was located kind of out next to an exterior wall top, right where the roof pinched down over that exterior wall, and so it was a pretty small volume of space above that bath fan in the attic, if you can picture it. And so any time anyone would shower, turn on the fan and that fan not being air-sealed from the attic side, a ton of, a high concentration of humidity and moisture was in that location, and it was leaking up into the attic space. And as soon as that warm, humid air hit that cold roof deck, it condensed. And so during this really long cold spell that we had, this layer of frost just kept building and building and building underneath the roof deck, and then the first warm day we got, that sun came out, temp got above freezing and all that frost started melting and dripping down the roof deck and then dripping down the exterior wall, and this person had no clue why they were having water coming out of their window below this bathroom on the exterior…

 

RS: Oh my goodness, yeah.

 

TM: On the exterior wall. So even new construction houses can have these problems with these attic bypasses and warm air leaking up into the attic. And we didn’t mention this before too, but we get tons of calls and questions about frost in people’s attics too. They may not have ice dams, but a lot of people suffer with frost, and it’s the same problem, it’s this warm, conditioned air getting into this cold attic and condensing on the underside of the roof deck.

 

RS: So how do you fix all this? 

 

TM: How do you fix it? You try to stop that warm, moist air from getting into the attic in the first place, that’s how we stop it. So it’s sealing up all of the… Physically sealing up all of those little pathways that the air is leaking into the attic, and that can be a difficult and messy job as you can imagine. Right? 

 

RS: Yeah, definitely.

 

TM: And that’s if you’ve got an attic where you can physically get into it and find those leaks, dig through the insulation and seal them. And a lot of times if you hire an insulation company, they will either have to remove some of the insulation to seal up the leaks or they might be able to push all the insulation to one side to seal those leaks and then push it back and blow new insulation in, but it’s pretty labor-intensive to do some air sealing. And I’d say a lot of houses could benefit from doing… Just not having to remove everything and seal every little hole, but going for the big ones, going for the big holes. It is expensive, and it is a lot of work to do that, but there are some houses too, where you just, you physically can’t get into the attic space, and it may not be possible to do that air sealing and adding adequate insulation. And we’ve talked about that on this podcast. You know where I’m going with that, Reuben, right? 

 

RS: Yeah, perfect.

 

TM: What are the types of attics and roofs that are really difficult to air seal, insulate? 

 

RS: Well, cathedral or one and a half storey. I mean, on a lot of those, one and a half storey, you’re stuck. You’ve got this part that we call the slant wall, where it’s between the two attic spaces. You’ve got the lower towards the outside of the house, and then you’ve got the upper attic right at the top in the middle, but then you’ve got the space that connects those two, we call it a slant wall, and it’s usually a 2 x 4, and you’ve got drywall on the inside, you got shingles on the outside. And in between those two, you’ve got about 3 1/2 inches for whatever you wanna put in there, and usually we find maybe 3 1/2 inches of insulation, maybe 2 1/2 inches of insulation and a one inch airspace, but whatever it is, it ain’t gonna be enough to prevent ice dam. I know from experience, I tried doing it the best I possibly could. I had an insulation contractor tell me, “If we do spray foam, closed cell, high-density spray foam,” this is like R6 1/2 per inch or something, “we’re gonna fill that whole cavity with closed cell foam and you’ll be good.” Well, the studs themselves were enough to allow heat through the attic and still cause ice dams. So I don’t care what you do with that space, it’s not gonna be enough to prevent ice dam. It’s, you can’t fix it.

 

TM: Wow. Even your insulation contractor was misinformed…

 

RS: Oh yeah.

 

TM: About how heat loss happens and kind of the expectation. They didn’t set proper expectations with you…

 

RS: No, they did not.

 

TM: When they told you to close cell spray foam. And that just, it blows my mind that there’s so much, there’s so much confusion in this industry about ice dams. And really, it’s just a matter of that heat loss happening. And those storey and a half houses, like you said, even if you try to insulate in between those rafters the best you can, you still have thermal bridging and heat loss through the framing that you really can’t stop.

 

RS: Yeah, compared to metal, wood’s a pretty good insulator, but compared to insulation, wood is a horrible insulator. It’s all depending on what you’re comparing it to.

 

TM: Right, right. And there are… And we’ve talked about this before on the podcast too, there’s ways that you can try and reduce that thermal bridging by adding a layer or a thermal brick insulation either on the inside of that framing. You lose headspace and you gut the entire interior of your house, but you can add insulation to the inside and try and reduce that heat loss through the rafters, or you could do something crazy and add insulation to the exterior and put a double roof deck on, but that is, we’re talking tens of thousands of dollars to do that. And is it worth it in the end? And so…

 

RS: Yeah, and all of those things will fix it, I say you can’t fix a 1 1/2 story house, you absolutely can. It’s just you can’t use conventional methods, you gotta go crazy.

 

TM: Yeah, the hard part is, you’ve gotta find a contractor who can do those things we’re talking about. As you know, it’s hard enough just to find a good insulation contractor who knows to apply spray foam correctly.

 

RS: Yes.

 

TM: So that’s a challenge, but what do people do if they have those cathedral ceilings where they can’t physically get in there, air seal, add more insulation, or a story and a half or a point 0.75 story attic, where they’ve got these slant spaces where they can’t get in there, what do we recommend to people that have houses like that? 

 

RS: Well, then it comes to prevention from the outside. It’s kind of more of the brute force method where you get a roof rake and you do all this other stuff, but I was thinking, there’s more… I wanna dig into on ice dam prevention. I wanna get into some of the nitty-gritty details today. Let’s save ice dam removal and prevention from the outside, let’s do another show next week. And maybe today, let’s talk about some of those nitty-gritty details like furnace ductwork balancing and how that applies to the stack effect, and let’s talk about bath fans exhaustion under the roof and clothes dryers exhaustion under the roof, and the valleys and how valleys affect ice dams, and how you can’t vent a valley. Let’s get into some of these details, Tess.

 

TM: Okay, let’s do it. You just name some things we don’t really talk about too much on the podcast, but they can all contribute to ice dams as well, roof design, valleys, locations of penetrations that exhaust warm air onto the roof, like dryers and bath fans, those are all contributing factors that we don’t shine a spotlight on that often.

 

RS: No. Let’s get into it. First off, roof design, why does the roof design even matter when it comes to ice dams? And I’m looking across the street at one of my neighbors with a bunch of valleys coming together and a bunch of icicles coming out of the bottom of where all these valleys converge. Talk to me about this, Tess.

 

TM: You have a great class on this, Reuben, talking about roof designs and how shedding water really impacts the performance of a house and how that water is shed, where that water is distributed, and a lot of roofs today, especially on new construction houses, it seems like the way that we’re designing them is with a lot of these Gables. You already mentioned kind of these triangles that we put on these roofs to make them more architecturally interesting. They’re not… Kind of that simple… If you can picture like a 1950s Rambler house, a single-story ranch that has a very basic hip roof, where if you look at it and it’s just a flat surface on one side and each side is just one flat surface, and all that water that hits that roof drains down, and it’s evenly distributed around the perimeter of the house. That’s a very simple roof design, but what we’re talking about is a roof that has lots of complex angles and triangles and gables. And the challenge with that type of roof system is that when that snow melts, it can get funneled to one location, all that liquid water and then freezing at the eave and then more liquid water building up behind it. And so you’re basically just kind of funneling all of this melted snow to one location. And obviously you’re gonna have worst ice dam problems with the roof design like that than you would with just a simple hip roof.

 

RS: And Tess, how do you vent a valley area? 

 

TM: [chuckle] That’s another good point too. You can’t.

 

RS: You can’t.

 

TM: You can’t get great ventilation. Yeah.

 

RS: Sorry. No, I mean, if you take a valley, you take the bottom of the valley and you do a square that begins at the bottom of the valley and it goes to the top of the valley, perfect square, all of that area is gonna get no soffit ventilation. That’s just how valleys work. Sorry, can’t vent that area. You can have vents up high, but you can’t have any low vents. And while we said that vents are not the cause of ice dams, they definitely are a factor. I mean, you still are supposed to have roof vents, and that’s just an area where you don’t get any vents. Even the most perfect roof, brand new, everything is perfectly air-sealed and all that, you get a ton of valleys in a big area, and while it’s not ideal. And there’s no fixing that, that’s just what you got, but it does make a roof more prone to ice dams when you get these big valley areas, for sure.

 

TM: Well, and let’s talk about roof venting a little bit more too. There’s a lot of older houses in the Twin Cities area that doesn’t have soffit intake ventilation. They were just designed without it.

 

RS: Yup. Yup.

 

TM: So how do people determine if they have… If they have soffit ventilation or they have attic ventilation? Well, the first thing you can do is look up underneath the overhang and are you seeing any sort of vents installed? And there’s lots of different styles. It could be round, it could be a rectangle, but do you see any sort of vent that looks like it would allow air into the attic space. And then it’s also important to actually see if there’s any communication into the attic space, if there’s actual proper vent chutes installed, or if the insulation has been installed without vent chutes, because you can have a soffit vent on the outside of your roof, but if it’s blocked off with insulation on the inside and there’s no pathway for that air to move from the soffit vent into the attic, then it’s not doing any good.

 

RS: Yeah, yeah, that’s right. So good way to figure that out is get up in the attic and put your head as close to the sheathing as you can, watch out for nails ’cause there are nails coming through the sheathing, you will poke your head if you’re not careful, but get your head as close as you can to the sheathing and then sight down all the way to the soffit and you should be able to see some daylight.

 

TM: Yes. Yep, that is a really good tip. You should be able to see day light. And in newer houses today, you’ll see these either pieces of cardboard or styrofoam kind of sandwiched in between each rafter at that exterior wall top at the eave, and that piece of cardboard or styrofoam is supposed to allow an airspace, at least an inch and a half, for that air to flow up from the soffit into the attic space. And that keeps the insulation from blocking off that airflow.

RS: Yeah. Yeah. And then we also talked about vents, like clothes dryer vents. Now, there’s a lot of reasons to never vent your clothes dryer through the attic space. A big one is how do you clean the terminal? We know that those clothes dryer vents, the terminals get dirty over time, within about a year or two. You gotta go to that terminal and you gotta wipe all the actual lint off of there, make sure it’s nice and clean. And if it terminates at your roof, who’s supposed to be climbing on the roof every year to clean that? It just… It seems like a stupid spot from that standpoint, but when it comes to ice dams, what are we doing, Tess? 

 

TM: It’s not a smart idea for ice dams either. You’re just dumping a bunch of hot moist air onto that roof, melting the snow and adding to your ice dam problem. So I’m not a fan of dryer exhausts on the roof.

 

RS: Yeah, when I’m in charge, no more.

 

[laughter]

 

TM: Right. Right.

 

RS: Yeah, and none of that, but clothes dryer is gonna push all of that exhaust up, all that lint up and out. It’s gonna work harder. We saw a new construction detail recently, Malin shared a picture on the Facebook where they had it going down and they vented it out through the rim space. So unusual to do it that way. Or maybe it was a bath fan they did it that way with, but whatever it was. Who cares? It’s a smart way to do it.

 

TM: Yeah, well, and another thing too, we didn’t mention, but you know that dryer exhaust pipe is gonna be really warm, hot even because drying your clothes on high heat, and so even though it’s insulated somewhat, it’s still going to be dumping heat into the attic space.

 

RS: Yup.

 

TM: Which is the opposite of what you want. In the winter time here in Minnesota, you want your attic to stay as cold as possible, so you’re not warming up the roof deck and melting the snow. So the worst thing you could possibly do is add heat sources to your attic, like a dryer exhaust or bath fans or ductwork. That’s another one. We haven’t talked about that.

 

RS: Oh yeah.

 

TM: But we see houses that have duct work in their attic, and this could either be a retrofit situation where you’ve added a furnace or four stair to the house at some point later on and you’ve located that ductwork in the attic, worst-case scenario, the furnace is in the attic, which we do come across that too. But again, it’s just a huge source of heat in that attic space that you’re trying to keep cold.

 

RS: Yeah, yeah, and then one more source of heat, when you’re talking about this, is recess lights, you already touched on it, but I’ll just tell you. There was a troubleshooting inspection I did once, this is probably about a decade ago, and we couldn’t quite figure out what was going on. There was no obvious air leaks, but for every one of those recess lights, I could find the recess light through about 16 inches of cellulose insulation. This guy had his attic re-insulated, but then I went upstairs and I counted, and the guy had 46 recess lights, all with incandescent bulbs.

 

TM: Oh boy.

 

RS: And there wasn’t any one room that just had a ton, it was just that every room had a fair number. And it was a lot, a lot of different rooms. And when I counted them all up, I went, “Oh, holy cow, this is what’s going on.” I could see all these hot spots all over the attic. Recess lights definitely contribute. And if you wanna reduce that, number one, use LED bulbs. They generate way less heat than incandescent bulbs. Number two, add a bunch more insulation, heap the insulation over your recess light. That’ll certainly help.

 

TM: Yeah, I mean, the proper way of, if you’re gonna have a recess can light is to build a rigid box of insulation, put it over top of that can light and then foam around the base of that insulation box to the attic floor, like seal it with foam so that it’s air-sealed, and then blow in more insulation over top of that, so that it’s air-sealed and insulated. But you can’t always do that.

 

RS: Not only that, but Tess, you know what, here, I’m gonna come right out and say it, I’ve never said this before, recess lights need to go. There’s no reason for a recess light ever again. And I’ll tell you why. I like recess lights, that’s all I’ve got here in my office, but I talked on the podcast about how I had this… My exercise room got destroyed when I had this water heater leak above it and had to redo that whole room. And when I re-did it, I wanted some lights in there, I had one light in the middle, it was terrible lighting. I wanted recess lights ’cause I really like them. And they’ve got these new ones that you buy, and it’s this little pancake thing, it’s about one inch thick. It projects…

 

TM: Those low profile ones. Right? 

 

RS: Super low profile. It’s just slightly thicker than drywall. It projects just about nothing up in your attic space, and it’s LED, so it’s all self-contained, it’s less money than a recess light, you don’t need to find framing to attach to. It’s not all these special… It’s not this big monster of a thing. It’s a tiny little disk, so why do we even have recess lights anymore, Tess? 

 

TM: That is a really good question, Reuben. You know what though, I was thinking that’s a bold statement, but I agree with you. I do. And if people are installing those old boxy leaky can lights with an attic space on the other side, they should come with a warning.

 

[laughter]

 

RS: Yeah. Yeah. They’re gonna wreck your house? 

 

TM: Yeah, I’ve seen so many problems with recess can lights in our cold climate where people get frost up in the attic, people get snow melt because of them, and it’s just… It’s such a battle. So I tend to agree with you on that. What happened when the bulb burns out on those low profile lights, do you know? 

 

RS: Next topic.

 

[laughter]

 

RS: I told you replace it, but it’s not a big deal to replace them either. I mean they just… It’s held in place with a couple of clips, it’s like grab onto it, pull it down, and it un-clips itself, and it got this little modular connector that clips together. You don’t need to be an electrician just to it apart. So I’d say you replace it, but with the life of those LEDs, feels like it’s gonna be a lifetime fixture. But one other thought… We’re gonna have somebody who’s listening to this podcast saying, “Oh, they’re leaky,” but we have airtight recess lights. And if you have a problem with the recess light it’s because you’re putting in a recess light that’s not airtight. And we all know that they should all be airtight in Minnesota, and that’s been the standard for the last couple of decades. Yep, I gotcha. And to you, I’d say look up the definition of airtight. It’s not airtight, you can see light coming right through those things. Airtight means that you have less than, what is it, 2 cubic feet of air leaking per hour or something like that. It is absolutely not airtight. It just means that we’re getting closer to airtight. That’s all it means. So there is no such thing as an airtight recess light.

 

TM: Yeah, yes. True.

 

RS: All right. Okay. All right. I need to calm down.

 

[laughter]

 

TM: You know, I think that the bottom line is that most houses are gonna have some sort of air leakage happening that allows that warm air to get into the attic space. If you haven’t already work with a good insulation contractor who can do some air ceiling work for your attic space, and then, of course, you wanna have adequate insulation in your attic, which… What are we requiring now, is it a 49 in Minnesota? 

 

RS: That’s right.

 

TM: Okay. So…

 

RS: That’s the minimum in Minnesota today.

 

TM: That’s a lot of insulation. Most houses, older houses don’t have that. So do your air sealing first, then do your insulation, work with a good contractor. We didn’t say this, but talking about vent chutes, I’ve seen so many houses where people have added more insulation thinking that’s the problem, and being told that too by insulation contractors and other builders, “Just add more installation. That should fix the problem.” And it can actually make the problem worse.

 

RS: Yes.

 

TM: More and more insulation, and you cut off all the ventilation from the eave, you block that airflow, you can make the problem worse. If you add more insulation without sealing those attic bypasses first, you can make the problem worse. So order is really important here. Make sure you seal those attic bypasses first, make sure you add more insulation, make sure you don’t make the ventilation worse. And hopefully, that should fix most of the problems. Although as we have said, not all houses you can fix the problems. And so then there’s other methods we’ll talk about in our other podcast.

 

RS: Yeah, yeah. We’ll tee it up for next week’s show.

 

TM: Yeah.

 

RS: All right, cool. Well, I’d say we’ll call that a wrap. So thank you everyone, you’ve been listening to Structure Talk, a Structure Tech presentation. I’m Reuben Saltzman, for Tessa Murray, saying God’s speed.