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How New Homes Waste Energy


If you think energy waste is something you only find in older homes, and that new homes are all built with energy efficiency in mind, you are seriously mistaken. A lot of new homes are built with no regard to energy efficiency whatsoever. Sometimes it is because building codes are not updated to meet new energy efficiency standards. Sometimes it is because the builder is unaware of current best green building practices, and sometimes it is simply because they are trying to cut costs in a tough economy and spend more on visible features like energy efficient windows, and green roofing, while forgetting proper insulation and air sealing.

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Hi, I'm Larry Janesky from Dr. Energy Saver. Today we're at a new house being constructed and Dr. Energy Saver is actually installing a efficient heating and air conditioning system with a properly sized and installed duct work system in this house. But I wanted to show you some of the details that are built in to a house that make it energy inefficient and why millions of homes out there have these problems. Let's take a look. Okay, here we have a flex duct coming across a supply run and we're going to have tray ceiling here, but we can see that that flex duct is above the joist bay. It's on top on the ceiling joist over here, and then over here comes down into the ceiling joist bay. And the insulator is not going to be able to get a battt fully fluffed around and underneath this duct.

So, there's going to be some compromise made there where there's a gap in the fiber glass, and this is where blown in insulation really excels, provided it's installed by someone who is careful and conscientious. You can blow insulation underneath that duct, fill all those odd shaped cavities around the duct, and then continue to blow on top of the duct and really do a good job with blown in insulation where batts very difficult to get them fitted to all these odd shaped spaces and compromises are made all the time that allow cold spots in the ceiling. We also know that we're going to put our 38 batts in this ceiling and Department of Energy calls for our 60 in our climate, so even a brand new house could use more insulation in the attic.

Here we are in the attic, and we're going to have a tray ceiling in this master bedroom. And so the elevation of this joist is higher than the ceiling joist in the rest of the house. And there's a slope transition that it's going to make but, again, a lot of detail for insulation to be installed and, you know, around all these framing we're definitely going to have gaps. I mean, the insulator is not going to be able to get batts fitted in here to where there's no gaps and we're going to have some issues there. We have a duct system that is put in with self-adhering take off boots and we don't have problems with leakage here coz it's a modern duct system. But, typically, we're going to have duct leakage around here in an existing home. So we're pretty good over here. This insulation could use to be taped. We also have our six duct wrap here and it's not just enough. If we're really going to have an efficient home, we need to add insulation to this duct if it's going to be in an unconditioned attic. Now, this, the duct guide did a great job. It certainly meets code, but code just isn't enough. We have 140 degree attic in the summer and we have our six insulation here, not enough.

Now, here we see we have this cavity here that forms this intersecting gable in the front. And if we had any issues, if we had can lights out there, for example, we'd have to get out there to seal them. And sometimes when they sheathe the roof, they'll put the roof sheathing on straight across these rafters and then they'll build the intersecting gable or dog house on top of that. So, in order to seal around any can lights that might be out there, we may have to cut a hole in the sheathing to get through there to get into that space to do that sealing.

Now, this house isn't completed yet, but, if it were completed, we would see more holes where air could get up into the attic, could be can lights, pipe and wire penetrations, various building assemblies, ceiling around the -- where all the ducts go through the ceiling. The drywall is going to cut a hole around there and there's going to be a gap between the sheet metal boot and the drywall. Those are all places where air could leak up into the attic that are going to have to be addressed. If we don't think that air is passing through wall cavities, take a look at that. We have gaps here, you could see daylight, you could see daylight up here.

So, there's plenty of air leakages. It can be vinyl siding and air is going to come right in through these gaps and go up the wall cavity pulling heat with it when washing our insulation with it. Now, here is two by six wall cavity we could put R-19 batts in here. But here where the header is the insulator is probably just going to squash the batt here and compress the batt. And when you compress the fiber glass batt, you lose R value. It needs to be fully fluffed in a sealed cavity to get the R value that's on the batt. Okay, here the plumber by code sealed around this pipe was fire caulk, but look I could drop this nail right down to the basement, so.

This is plastic tubing for our hot and cold water supply lines and we see that there's gaps around here. And this is typical and nearly every house that ever built we have gaps around pipes and wires. Plastic problem, we got a cantilever, okay, that means the floor joist stick out over the wall so that second floor is bigger than the first floor. So, look here, the floor joist stick out another 18 inches or so. That floor is outside. And then we have a hole for the plumbing for the Jacuzzi tub, all right, so air from that cantilever is not sealed properly. Air will -- cold air will get in between the floor joist between the first and second floor and could go right up underneath that tub and affect what's going on with the plumbing. And it's going to affect the back of the house as it is. But, I mean, the real answer to that is to seal it properly and insulate it properly, that cantilever.

Here's the basement door and this is just a walkout door like any door. And one thing that we can see is that we have a shim space here, okay. This framed opening is framed two inches bigger than the door. So this is a six foot door, a two-three o doors, so it's six foot, and we framed the rough opening six-foot-two. So we have a jam that's five ace or so. And then we a shim space, we can get the door plumb and level. But then we have a space around the door and that provides a place for air to get in. So when -- one way to seal the shim space afterwards is perhaps to drill small holes up in here behind the weather stripping, eight inch holes where we stick the needle of our foam gun in there if you have the right foam gun that takes a needle and you could squirt foam in here and you're going to use a cup, maybe a can and a half of foam to go around this door. But that's how you can do it after the fact. We take a look here we have -- this is a stud and here's a jack stud.

Okay, the jack stud holds up a header. Here we have the way this header is constructed. There's different ways of doing it. They've left it shy, okay, and probably are not going to put in any insulation in here. If they put fiber glass batts in this wall, they'll put fiber glass batts in these cavities, but here there won't be -- there'll be a gap, and that makes a gap in our thermal boundary. Of course, the header is not -- the wood is thermally conductive than insulation, so it's going to be a cold spot in this wall where the headers are. If we take a look here, we have the foundation wall. We have a treated wood's -- this a sealed plate. This is a doubled sealed plate and we have an opening. We use seal sealer, which is this foam sealer. But I can stick this piece of sheet metal right out to the outside. You can see daylight right through here pretty well. And what they'll probably do is take -- when they side the house, they'll take a little five quarter by three or four piece of trim. It will cover up that space outside but air still leak in through there quite a bit. So that's a place where we get air leakage. Here's a window and the window, again, has a shim space around it. So this is an area of concern. Now, you'll notice on this window they put the vinyl window in and we still have studs showing. This is a two-by-six wall, so that's good. We can get more insulation in the wall. But they will put an extension jam on it.

This is -- this would be called an extension jam to come out to -- past the drywall and then it could be trimmed. So that's -- that would need an extension jam. Now we go around here, we can see that there's a gap between the stud and the foundation and that would need to be sealed. And we take a look up there and we can see gaps in the seal plate, okay, and if there were gaps in this seal plate, that will be an area where air could leak in pretty readily. But you can see the double sealed plate and the gaps up there. Here we have two duct chases, one return and one supply up to the second floor. Once these chases get to the attic, they're going to go cross the attic floor and then the takeoffs, the flex runs are going to come off of there. Well, this is pretty good.

The mechanical contractor, in our case it's us, didn't cut a giant hole in there so we can have a giant hole around there. But, typically, there's a big hole around these duct chases to the attic and you'll have basically the express way for air to get from the basement to the attic. As it is, there is about a quarter of an inch even a quarter of an inch space around these ducts and that would have to be foamed because that goes right up to the attic. But we have a laminated girder, okay, and our joist are on top of the girder. And in the foundation they put a block of wood and formed a girder pocket. Now, there's a space on either girder pocket, but this does not leak air. We can see that there's concrete. That girder pocket did not go all the way through the concrete wall to the outside, okay, it just went halfway through the wall, and so this would not leak air. We can see over here that you can see daylight around that electric service line, so that would be a place where air would definitely come in through the rim joist and so we would definitely want to seal that. The electrician drills, a two and a half inch hole for a two and a quarter inch pipe or two inch pipe and we have a gap around that. Here's a place where we have a pipe going out the front and I believe this is for septic line. And so here's a gap around here.

Now, we're concerned about water coming through here but we're also concerned about radon gas coming through here as well. The basement is going to be depressurized, can be sucking air in from wherever it can, and a lot of times these pipes they go out to the septic tank and then go out to leaching fields, will be backfilled with clean -- it could be sand. They might use bank-run gravel, which is core sand, and air can come through there around that pipe and get sucked in there. So that would have to be sealed much better to prevent water and radon gas and unconditioned air from coming in and through here. You'd be surprised. Are we worried about air coming in from the ground? Yes. And you say, well, it's dirt, there's no air in there. Well, there's lots of air in there and we can suck air through that soil by the stock effect, so that's where radon gas gets in, in the first place. Why doesn't it stay in the ground and mind its own business? Well, because we're sucking it in and when we suck air, and radon comes along with the air. Okay, now, here's another issue and this is, you know, these are all very common problems. This is not unique to this house. This is, you know, nearly every house is built with these problems. And that's why Dr. Energy Saver exists to come in and fix these problems. These are why houses are less energy efficient than they could or should be. Here, we a tub that's a Jacuzzi tub that is built-in to a platform. And this will be tiled probably, okay, and all covered in. Behind here there's going to be all plumbing. There's going to be the pump to run the water through the jets and so forth. But you see this platform was framed before the drywaller was here. So the drywaller is going to come, down, run the drywall to here. Now, the drywalls are air boundary in the house as it is in every house. And under here you can see, hello, okay, no, I put my hand here. There's going to be no -- nothing preventing air from the outside wall cavity from getting in underneath the tub. And just -- in fact, in this town just several days ago we did a job where we -- the home owner had a pipe freeze underneath the tub. And, in fact, with the thermal energy camera it was 48 degrees outside, we saw that the temperature of the inside of the tub was 51 -- 51, so it's just three degrees warmer here than it was on the outside because there was a connection between outside and underneath the tab.

Now, we look at -- we have holes for the sidewall brackets that are not going to get sealed and air could get into this cavity underneath the tub and cause problems. So the solution is to run drywall all the way down to the floor before we frame the platform for the tub and that will keep the outside air from getting underneath the tub and keep the tub and all the plumbing in conditioned space instead of being connected to the outside. All right, here we have a soaring foyer here and we have a round top window. And if we look at the way it's framed, you know, square framing round window and we just have a whole cut in the sheathing and we have an odd shaped space to insulate there.

So chances are, you know, that's not going to get insulated properly and we're going to have a thermal week spot in the wall assembly there. And we know that with a lot of glass, you know, some of these foyers have glass from the bottom all the way to the top, a big wall of glass and the glass is always going to be colder than the wall. We have R19 here, six inch wall, and we're going to have -- the U value of these windows is .3, and if we divide -- actually the U value there is .28, so that's a little bit better. One divided .28 is 3.7 or something, so the R value of this window is 3.7. The R value of the wall, R19. Clearly, the window is always going to be cold. So if we have a wall of windows, we're going to be cooling the air or always going to feel a draft. In fact, people might say, whoa, that door downstairs is very drafty, very leaky. Well, it might not be the door that's leaking. It's going to be this big wall of windows that's constantly cooling the air, and the air is descending, hits the floor, crawls across the floor, goes up the interior wall, across the ceiling, repeat, okay, so we got a convective loop, and the door gets blamed for all the leakage.

Now, the door might leak a little, too, but this big wall of windows is likely to blame. All right, here we have chase from the basement to this -- to the attic where the return trunk comes up and the supply trunk comes up and in this case the HVAC contractor has used a metal L channel and fire caulk to seal around these chases but they're not sealed a hundred percent and air can still get from the basement right up to the attic which is really the expressway for the air. Now, this is a modern house, before 1990 or so we would have a chase, a huge chase. In fact, all this space here might be cut out where air could get from the basement right to the attic. We have many houses where you can look down from the attic right to the basement floor two-stories, and huge air leak throughout the house. So that would be a big priority to seal it at the top in the attic. If we had a choice do we want to seal at the basement sealing or at the attic floor? Always seal it at the attic floor. Why? If we seal it at the basement ceiling, then any air that got into this chase cavity through the first and second floor through electrical outlets, through between the drywall and the framing between the subfloor and the framing -- any air that got into this chase can still leak out at the top.

So I'd rather -- if I was going to do one or the other, I'd rather seal it at the attic floor and catch it there. Here we have the plumber has drilled a pipe through the bottom plate and he sealed it fire caulk. But that is not normal. That's new. The code requires that and in old house that would be a gap right through between floors and right to the basement and right to the attic. I mean, you see that hole there is more important than that one because it goes to the attic, but it is sealed but in older houses -- how do I say -- not that much older. These are going to be open all day long. Okay, here we have the electrician drilling holes for wires, and wires are going to go through there and there's going to be a big hole. Again, this is between floors. I'm not so concerned about that, but at the top going to the attic that would be a big issue and we're going to seal around there.

Now, my understanding is the code at this point requires the electrician to seal around those wires with fire caulk, but, again, most houses, there is millions and millions and millions of houses out there with holes for wires that big and wires going through them that's that big and they have a lot of space around them. If you're building a new house, you're going to have to live with it a long time. If you'd like advice on how to keep it energy efficient forever and ever, call Dr. Energy Saver. We'd love to help you.

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