01 Apr Efficiency Issues To Watch Out For In A Custom Home
Custom Home Efficiency Podcast Transcript:
Hey there everyone, welcome to another episode of the Custom Home Builder podcast with Jason Black, the presentation and owner of Artisan Signature Homes, Louisville’s best-known and most accomplished home builder. Jason it’s always good to see you.
Jason: Good morning Greg, good to have you back, sir.
Greg: And talking about being back, we have Eric George back with us again, from Building Performance…
Jason: He was so informational that we drug him back to tell us a little bit more.
Greg: We could have gone for our first hour long podcast last time he was in the studio. We could have just gone for the whole thing.
Jason: I saw a lot of yawning and a little bit of dozing off, so I think it was good we split it off into two episodes. Tell us where we ended up, Greg.
Greg: I think we talked about fireplaces, knee walls, vaulted ceilings, and tray ceilings, ductwork, and basements, so those were five of the issues that Eric felt were really … needed to be considered when building a new home that led to comfort issues. Is that correct?
Jason: Yeah, so we can hit five more issues. I guess, I don’t know if we want to call it number six or number one, but Eric lead us off here.
Eric: All right, so again, in no particular order, we’re gonna talk about kind of the bottom five here. The first one on the list is heat pump systems. We talked briefly before the podcast started about dual fuel systems or hybrid systems, and those are great if the heat pump part of that is efficient.
And unfortunately, a lot of the times, heating and cooling contractors will sell a client or a builder on these dual fuel hybrid systems, but then they’ll put a entry-level heat pump on there with a nice gas furnace back up. The problem is the heat pump runs 60 to 70% of the time throughout the year, so if that heat pump is not efficient, then there’s really no benefit there to the dual fuel hybrid system.
Heat pumps, in general, especially in the winter time, are going to cost you more than a gas furnace will, at least where we are. Because if it gets down to say 20 degrees outside and the heat pump is not able to produce enough heat to keep up, it will switch over to the emergency back-up heat, and that’s basically like heating your house with a hairdryer, literally. I mean it’s just a resistance heat coil …
Jason: It doesn’t sound like a very efficient way to heat your house.
Eric: Not a very efficient way to heat your house, and that will jack up your utility bills real quick, so if you’re gonna use a heat pump system, make sure that it’s a higher efficiency one. Something that has what’s called a HSPF rating, which is a heating seasonal performance factor, of like nine or higher. Most entry-level systems are gonna be around a eight.
Jason: But your preference is, if you can do a gas, go ahead and go for the gas, comparable unit to the heat pump.
Eric: Yeah, I would prefer going with a two-stage or a multi-stage gas furnace versus a heat pump, or go with an efficient heat pump, a dual fuel system that has an efficient heat pump on it. Everybody is gonna have a little bit different opinion. I’m just a fan of gas. The heat from the air that comes out of a gas furnace is gonna be like a 120 degrees versus about 90 degrees, where it comes out from a heat pump system. It just feels warmer.
Greg: Can I back up a little bit and have you explain, just quickly, what a heat pump is so that everyone listening … Maybe it’s just for me, so that I know exactly what you’re talking about.
Jason: So everyone… “like me?”
Greg: That’s right!
Eric: So Greg, a heat pump basically works like an air conditioner in reverse. There’s an outside unit where it takes the heat out of the air, even when it’s really cold outside, there’s still heat that can be captured in that air, and that heat is basically transferred through a refrigerant line into the house and into a heat exchanger, and then air moves past the heat exchanger to heat the house.
So it kind of works the same way an air conditioner does, just in both directions. So an air conditioner takes the heat inside the house, moves it past the coil, and that heat is transferred to the outside condenser and is released into the air. The heat pump just works in both directions.
Greg: And then the gas unit just takes the heat from the flame?
Jason: So there’s no outside unit needed for a gas …
Jason: Or a gas unit?
Eric: Correct. It’s only for the air conditioning part of it.
Jason: Greg, have you learned something today? That’s what I want to know.
Greg: You know what, you’re joking about how long this episode’s going to be and the last one was … I’m learning a ton. People are gonna think that I have to say this ’cause I’m on the podcast, I’m learning a ton. Its actually quite informative. I’m a little embarrassed by how little … I mean everyone lives in a house, lots of people live in a house, how little I know about the house I’m in and, and the fuel that I use, and how it was built, and where all the leaks are.
Literally, I can walk through my house, and it was built in ’98, and it whistles. I mean there’s certain parts of the house where I know, when it’s windy, I’m like, “Oh, whatever, that’s my house.” And I’m sure Eric was just like, “Oh my gosh, you don’t just walk by a whistling house!”
Jason: I’ll be man enough to admit it, as a builder and building luxury custom homes, I’m still learning every day, and I’ve learned stuff today and last week when we had Eric on that I’m astonished that some of the stuff I’ve not heard of or Eric puts a different spin on it.
We’re constantly refining the building process and trying to increase the building performance of these houses. I’m all ears and love absorbing all this knowledge. I think we digress, where were we?
Eric: I think we were about to talk about zone systems.
Jason: Perfect, I love zone systems, right? You get each room the exact temperature you want, what’s wrong with a zone system?
Eric: All right, well let’s talk about them, so zone systems … It’s a fancy kind of add-on that a lot of home owners think that they need, and it’s probably because they may have had a zone system in a older house, and it kind of helped overcome some of the comfort issues that that house created.
My personal opinion on zone systems is that if you’re building a new house, and you have all the opportunity in the world to make sure that it’s insulated and air sealed properly, and that you have a HVAC system that’s designed and laid out properly, there shouldn’t be big temperature differences between one room to the next. And that’s what a zone system is kind of there for. It’s to overcome …
Jason: Is it like a bandaid for a bad insulation job?
Eric: Absolutely. That’s a great way to look at it. A zone system is a great bandaid for an insulation or air leakage issue.
Greg: So if you go into a new project saying I want the zone system, you’re just saying I’m giving myself an excuse for not starting off on the right foot?
Eric: It’s …
Greg: Is that a little too harsh?
Eric: It’s to no fault of the homeowner. I mean …
Jason: … or the builder.
Eric: … or the builder, or the builder. It’s just what they’re used to and it’s what they’ve heard and what they’ve experienced in older houses, but with new homes that are much tighter than older houses, and are much better insulated than older houses, you shouldn’t have these temperature swings between rooms if it’s all done properly.
Everything done properly, if you put in a new system, whether it’s a heat pump, geothermal, gas furnace or what have you, as long as it’s installed and sized properly, and the ductwork is sized properly, than you should be getting the same amount of heat and air temperature to each of those rooms that’s required.
Adding two or three or four thousand dollars for a zone system on a house doesn’t really make a whole lot of sense to me in new construction.
Jason: What are some of the issues with zone systems that you’re seeing? I think before we started we talked about your profession, and one of the most common things you see is zone systems causing issues.
Eric: A lot of times you’ll see a zone system kind of added after the fact, and it will be put on to a furnace or a heat pump that wasn’t really meant to have a zone on it.
Think about it this way, if you have, let’s just call it a gas furnace. You’ve got a gas furnace, and it’s supposed to move 1,000 CFM of air, that would be a two and a half ton system. If you have a zone system that has three zones to it, and it closes two of those three zones, it’s trying to force 1,000 CFM through basically one-third of the ductwork, and it could sound, literally, like an airplane’s about to take off in the house.
It’s just forcing way too much air through too small of a hole, right? What you do to get around that, or to avoid that problem is you put zone systems on furnaces or heat pumps that have variable speed air handlers and they have at least two stages of output so that if you only have one zone open, it’s gonna run at the lower air flow speed and the lower capacity so it’s not trying to force 100% of the air through one-third of the ductwork.
The other way that you could kind of help avoid some of the issues is to oversize the ductwork from the beginning, knowing that you are going to have a zone, and so you may be trying to force 100% of the air or whatever through one section, but it’s gonna be big enough to handle it.
Jason: So can you back up for a second and just explain maybe the difference … I know we’re talking about zoning on this particular … But you mentioned variable speed and dual stage?
Eric: Yeah, dual stage or multi-stage. Most furnaces and heat pumps in the past have been just one speed for the air flow and one output setting, so if it’s a gas furnace, and it’s a 100,000 BTU gas furnace, it’s gonna put out 100,000 BTUs of heat all the time.
A two stage or a multi-stage system might have a 100,000 as a maximum output, and then 60,000 as its lower output, and maybe even 40,000 as its lowest input. If it’s not needed … If a 100% of the capacity for that system is not needed, it’s not gonna run at 100%. It’ll run at the lower capacity, which saves you money on your utilities.
Jason: Where does the variable stage come in? Or the variable speed? I’m sorry.
Eric: The variable speed … if you have multi-stage or two-stage outputs, then the airflow has to match the output that is required, so if you change the output from 100,000 down to say 60,000 BTUs, you don’t want to move the same amount of air through the system that you would at the maximum output.
Jason: ‘Cause there’s not as much coming out.
Eric: Right, so it’s got a variable speed air handler. Most new systems that are high efficiency systems are gonna have some kind of a variable speed motor. Not all of them are gonna have multiple output capacities, so it’s real important if you’re gonna do a zone system in your house, you really need to have a variable speed blower on it, and at least two stages of output, if not more.
Jason: Okay, thank you. Awesome.
Eric: So that’s zone systems. Moving onto talking about bonus rooms.
Greg: Okay, is this one of the reasons that a lot of people have zone systems? The bonus room?
Eric: I’m seeing a trend here.
Greg: That’s right.
Eric: Yeah, so the bonus room is that are that’s above your garage. It’s always hot as hell in the summer time and freezing in the winter time. I’ve seen people go back and add a zone system, or add zone ducting to an existing system to try to overcome that really uncomfortable bonus room, and again, it goes back to, A, was the bonus room insulated properly to begin with?
Jason: Probably not.
Eric: Probably not; 99 times out of a 100, probably isn’t. And is the ductwork that’s going to that bonus room sized properly to provide the amount the cooling or heating that’s needed? Probably not. With bonus rooms, they pose a lot of challenges typically by the way that they’re framed.
You’re basically putting a room in an attic that is above a garage, so the garage isn’t necessarily insulated. It’s going to be a lot hotter in the summer time than the rest of the house. It’s gonna be a lot colder in the winter time as well because all you have to separate yourself from the outside is that floor.
So you’ve got walls on either side, they’re facing attic space, you have a floor that’s facing the garage, so you’re basically kind of just floating in mid-air around an unconditioned space.
Jason: Yeah, so you’re in contact with more outside spaces than a say a family room or a bedroom or something like that.
Eric: With those kind of rooms, you might have one or two exterior walls, and then a ceiling that’s between living space and exterior, with a bonus room, you’re completely surrounded.
Jason: So you’re almost in a tent.
Eric: Yeah, you’re in a windy, leaky, uninsulated tent.
Greg: This is starting to get depressing for me, sounds like you’re talking directly to me.
Jason: One of these days, we’re gonna get you a new house, Greg.
Greg: That’s right, absolutely.
Eric: The bonus room, if you’re building a new house, that bonus room needs to be insulated better, honestly, than the rest of the house. Those walls that face attic space, your attic can get to a 120 or 130 degrees, so you want those walls to have a lot of insulation in them to separate that space.
Greg: You talked on the last episode about insulating the knee walls properly and a vaulted ceiling if your bonus room has one, what do you do about the floor below the bonus room and above the garage?
Eric: Ideally, that floor cavity should be packed full of insulation, so whether you’re blowing in cellulose or fiberglass … Or you’re using fiberglass batts, it really needs to completely fill that floor cavity. And if it doesn’t fill the floor cavity, it needs to be supported so that the insulation is in direct contact with the floor, with the bonus room floor.
And then where the floor cavities go out to the side attics, you need to make sure that they’re blocked at the bottom so that you don’t have air that can basically move underneath from the floor from those two side attics.
Jason: Say if you’re doing spray foam insulation, would you fill that entire cavity …
Eric: With spray foam insulation, you can get away with maybe like five inches, four, five inches of foam on the underside of it, and then that would give you an R value of around like 21.
Jason: So it’s just not going to move the air through the insulation like a fiberglass would …
Eric: Yeah, when spray foam’s installed to a certain thickness, it is an air barrier as well.
Jason: Good to know, good to know.
Greg: Would that be cheating if someone put up like a gas heater in their garage to heat the space above it, the bonus room, is that, again, and indication that you’re not … You haven’t sealed your bonus room properly.
Eric: Yeah, it’s probably not insulated and sealed well. I’ve actually worked on a house where they had a radiant heated floor in the garage, mainly to keep cars warm in the winter time, but it was also supplementary to keep the bonus room above warm.
Well, guess how much of that heat is actually going out the garage doors and everywhere else, and not necessarily making it into the room above?
Greg: A lot.
Jason: A good portion.
Eric: A lot of it, yeah, so it’s … You’re spending more electricity, your gas, to be comfortable than you need to.
Jason: And that’s probably one of the areas where your expertise comes in for us is when we have those bonus rooms and knee wall spaces, that’s why I like that second set of eyes to look at them for me because … There’s those little voids or cavities that just are very very difficult to get right.
Eric: Yeah, bonus rooms can be challenging for sure…
Jason: All right. What do we have next?
Eric: Next one is gonna be cantilevers, and a cantilever is basically any section of the house that kind of sticks out from the rest of the house.
Jason: Like a bonus room?
Eric: Like a bonus room. The floor underneath the bonus room is a cantilever, essentially.
Greg: A bedroom sticking out over a front porch?
Eric: That would be a cantilever.
Greg: I get it, I get it.
Jason: You got one of those, Greg?
Greg: I got one of those, yeah.
Eric: Is it cold?
Greg: It is. My son complains frequently in the winter months.
Eric: Yep, and so usually those cantilevers are not blocked and sealed and insulated in a way that’s gonna stop air from moving into that cantilever, and into the floor space.
Jason: And so it sounds like a big problem with bonus rooms and cantilevers and knee walls is they might be insulated and have the proper amount of insulation in there, but there’s not an air barrier? Is that what I’m hearing from you?
Eric: There’s not air barriers or the framing was done in such a way that it makes it more difficult to insulate them, so yeah, if air moves through insulation, then the effectiveness of the insulation is greatly reduced.
Jason: Is that cantilever going to be treated similar to what we just talked about on that garage floor?
Eric: It’s gonna be the exact same way, so if you’ve got like a bay window, and the bay sticks out from the house, the bottom of that bay window needs to be filled with insulation ideally or spray foam, four or five inches. But the other consideration is where that bay window, where the framing for that floor comes into the house, that also needs to be blocked off.
So put a piece of foam board in there, put a piece of plywood or whatever, and seal it to the framing with foam or caulk.
Jason: So even if you are foaming it, you want to go ‘head and …
Eric: Still got to …
Jason: … block it.
Eric: … block that interior …
Jason: … the bottom portion of that.
Eric: Yep, kind of spray it like an L-shape and seal it off. So bay windows, second floors that kind of overhang the first floor a little bit for extra square footage, fireplaces a lot of times will have a cantilever underneath them, they’ll bump out from the house.
Greg: That’s a double whammy, right?
Jason: You beat me to it man, yeah.
Greg: Back to the fireplace.
Eric: I know, so, yeah. It kind of all goes back to the framing and how you’re designing the house.
Jason: And I try to avoid cantilevers a lot of times, but sometimes we need them architecturally wise. We’re just needing different elements, so if we do have one, we want to make sure we treat them properly.
Greg: Eric, do people like seeing you show up on the job site or …
Eric: It depends on who you are.
Greg: That’s right.
Eric: If you’re the builder and you like me, then obviously you’re like but … But sometimes the installation guys don’t like us so much.
Jason: You know, it is interesting because … And again, that’s why we have Eric come out because you may have an insulator … We were just talking before the podcast. I had a homeowner stop in and we were discussing his new home, and we met the insulator out. They’re saying one thing that is a little bit contradictory, is that right?
Oh my gosh, what they said was different than what Eric said! It’s our job to have an expert that is gonna educate our trade partners. Just because you’ve been doing it this way for 30 years, it could be wrong.
Eric: Or you could do it a better way.
Greg: And that goes back to what you were talking about several episodes ago that it’s worth your time to have the same tradesman come back because they learn how to work with you as opposed to trying to chase the 5% discount and someone will do it cheaper, and have no idea what your expectations are, or haven’t worked with Eric before … It just sounds like having a good solid crew coming in is well worth it.
Jason: Absolutely, absolutely.
Eric: Yeah, somebody that’s willing to learn for sure.
Jason: Yeah, and that’s what we like as part of our team, so I think that takes care of cantilevers. What number …
Greg: We got one more, one more. Number 10! All right, woop, woop.
Eric: This is another design thing, but the way that you orient the house, and if you provide any shading for windows and glass doors and stuff like that, you can’t always determine the orientation of the house because you’re gonna pick a lot in a neighborhood, and it may just be the corner lot with the best view or whatever.
When you design the house, if you know that the house is gonna be … like the front of the house is gonna face south or southwest, and you’re gonna have a lot of glass facing south or southwest, think about providing some kind of shading for that glazing. Whether it’s an extra large overhang for the roof to provide shading, or maybe it’s some kind of a covered porch for the entry way …
We see a lot of houses that face south with no regard to that entire front wall is virtually glass, and so in the summer time, the heat is just baking into that house, and unless the heating cooling contractor has sized the air conditioner to account for all that extra heat gain, then the house is gonna be uncomfortable, and you’re going to use a lot more utility, electricity cooling it down.
Shading for windows is important. The type of windows that you use is important.
Jason: Would that be like a glazing or a tinting on the window if you couldn’t do a tree?
Eric: You can add some tinting to the windows, you can also do those kind of decorative awnings that … on the outside of the houses. Certain neighborhoods may not like that look, but that is an effective way to do it. The other way is natural shading from trees and adjacent buildings and stuff like that.
All those kind of things go into account when I do an interview rating on a house, I take into account the overhang of the roofs, whether there’s buildings around or close by that are gonna shade the house. All those things affect the heating and cooling load requirement for the building.
Greg: Does this make a pretty decent size difference … This seems like something that home owners would pass right up. It doesn’t matter. I want the house the way I want the house, and I don’t care that my bill’s gonna be a little bit extra. This seems the first one that people were just like … whatever.
Eric: Yeah, you’re gonna design the house first, and then think about this after you move in, and you’re uncomfortable.
Literally, I mean it’s not gonna be really a consideration most people even think of, but the more windows that you have in a house, the less insulation you have in a house. The less insulation that you have in a house, the more heating and cooling capacity that you need.
And depending on what those rooms are where you have all that glass, you may or may not want to be in those rooms.
Jason: Yeah, and that’s what we’ve seen. That sun … it can really change the temperature of a room, especially like you said, it doesn’t have proper shading or proper glazing on those windows.
Eric: Yeah, I mean you can cook the floor right off, the color right off the floor sometimes.
Jason: Yeah, I’ve seen that, too. Move that rug after you’ve been in there for a few years, and you’re like, what happened?
Eric: It’s a lot darker over there.
Jason: I think that’s wrapping it up, and Eric, I can’t thank you enough for the information that you’ve shared with us over the past couple episodes, and I’m ready to go design the next house and see we can use all this great information we’ve learned.
Eric George again, why don’t you tell people how to get a hold of you and your company if they have an interest in your services?
Eric: Sure, absolutely. Website is BuildingPerformanceGroup.com, and our number’s 502-509-5535. You can also find us on Facebook and Instagram. Instagram is just Building.Performance, and we have a Twitter account as well.
Jason: All right, well thank you so much, and we’ll be seeing you around soon.
Eric: Thanks Jason.
Thank you for joining us on this episode of the Louisville Custom Home Builder podcast. If you’re looking to build a home, and would like to reach out to Jason with any questions about the process, or maybe just your individual needs and desires, please visit the website at ArtisanSignatureHomes.com. We appreciate your time with us today and look forward to bringing you another episode next week.