Hey thanks for watching this video. This is one class from the 2022 hvacr symposium in claremont florida. We have the symposium every year and so to find out more information, kind of upcoming go to hvacrschool.com symposium big thanks to our sponsors. For this event, which was accutools and truetech tools, they're the two title sponsors that made the event possible.

This session is with my good friend bill, spone from truetechtools one of the title sponsors of this event, and in this one bill is going to talk about the basics of building science and building performance for hvac contractors. Thanks everybody for coming into this session, um joe, is a guru on a lot of subject matter and that coming from bill, that's means a lot. So in fact, he helped me prepare this presentation that i did back in october for a radon scientist radon specialist at their annual conference in baltimore last october. So he helped me put this together and i thought well he's here.

Why not have him co-present with me? So we came up with this like 20 minutes ago and he's cool with doing it, because that's the kind of guy he is so i'm going to be like yes, that's correct that, yes, that is also correct and joe joe's got a great background. Maybe one of the best ways you can learn about it. I do a podcast too building hvac science next or this coming friday. I believe joe's episode.

My interview with him will be published, so you can kind of listen and hear. Like a more of an informal conversation with his background, what he's done is all his past experiences, but anything you want to add uh. No, i'm excited to be here. You know this is actually the you control the house more than anybody.

I i don't think you guys acknowledge that we're gon na talk about building science, but there's no other contractor that actually regularly impacts the occupants more than you do. A bunch of other people made a mess of the house and they're hoping you fix it and uh. We'll talk about the messes or ways to hopefully nobody did that for you, but again, you're, always the person that said: hey, i'm uncomfortable, you fix my house you're like well as your builder, who actually made the problem i'll do what i can you know and i Think it's important like building science, isn't a thing. It's a continuum of knowledge and you need you need to you know some people were sort of sheepishly raising their hands out there.

If you know a little bit about it, continue to learn more about it figure out how it relates things this this was a summary i saw just last week from a guy named trevor clark, who's from the isle of man. Do people know where that is. Okay. That's where they do the tt race, which is the motorcycle race since 1906, that has resulted in 146 deaths so keeping these abcdes.

I like the way it's summarized critical design points for comfort, health, durability and energy efficiency. Sometimes that's a lot of what you're being asked for when you're doing hvac work, so airflow airflow control, we'll talk about that in this session, barriers to preventing air flow, controlling airflow uh, the actual control devices dampness moisture, i mean you'll hear a lot about that in A lot of these different sessions and then air exchange this is to provide something to provide an environment that has fresh air in it to dilute the pollutants that are in the air. We recommend using data to back up your decisions. So, of course, i like that, because i sell test instruments, but i think it's it's a really great idea, because it allows you to to have something to uh to rest.

Your decisions upon and the sort of the process can be used in new and existing housing, and tomorrow i'll be talking about a new house that i built and where i tried to integrate as much as i knew about building science and hvac into this house. I'll be talking about our experience there, but also to draw from my network to to do that. People like joe, too and think about the building performance upgrades which can affect the comfort energy efficiency, durability, safety of the structure. Many of them are permanent.

You do them once they're, not consumable. They just keep working and working and working if they're done correctly and maintained yes, so there's some building blocks a couple. Things like you want to walk away with from any presentation, try to drive home one point: it's the point of ham, which i learned from anthony cox, is anthony here yeah. He is here anthony's here, so search him out.

Uh, anthony cox, great guy trainer from christiansburg, virginia heat, air and moisture are really important concepts to get under control. The enclosure provides the air tightness, the pressures you have to look at where they come from in this illustration. Here you can see things coming from the ground, so part of this was for the soil gases for the radon presentation i did and then what can be contained, the cargo that comes along with the in those air streams and then measuring and detecting them properly. So i'll talk about some bulk, moisture uh, it's something that uh, no matter where you live, you you are dealing with this one way or the other.

So you know it's not um. You can think about an example of so the most common example i use is that you have bulk moisture it's around the outside of the house. I see poor drainage all the time and i know that's something that is not a priority for you. But if you're trying to control comfort in a house that moisture that is draining back to the house isn't just deteriorating the foundation, it's figuring out a way to get into the foundation into the crawl space and has nowhere to go.

But back up through past your occupants, who are now uncomfortable and they complain to you about that so as you're walking around the house. Believe me it's okay for you to document that i saw some of your drainage issues. I saw signs you have water around here that actually can actually cause more moisture and uncomfortable issues for you. So it's more ac operates longer or doesn't complete its cycle.

All these things are because poor drainage you got gutters, do they actually distribute the water away from the house. So all these things are a compound, simple issue that most of us probably have poor drainage at our house. I think you're going to go home and you'd be like damn that joe guy was mentioning something. I see these issues and it's it and the problem is that, because it becomes compound once a little bit of water's there, it stays there and only becomes worse and worse.

So we build these homes. It'd be great: if we didn't put any windows or doors or anything in them, they'd be phenomenal, they would work premiere all right. We would have no issues, nobody'd be uncomfortable because they couldn't either get in or get out okay, but instead we cut all these holes into dang things and they make it really a challenge to control all of the heat air moisture. So but the reality is most of us think that it's all about these little holes that we have on the outside, where your hose bib is and that kind of stuff.

The reality is, it's actually more of a cheese, wedge issue where things are moving up and down through the actual structure. If you have multiple levels or these complex levels that actually makes it really difficult to keep things under control, that's where we're failing in terms of the design and all these architects or whatever would be like. Oh yeah. We wanted to have all these things.

We want to have multiple roof lines and other places and the uh. I don't care how you get your ducts there or how you're going to heat and cool it. That's not my problem, it looks great right and people are really uncomfortable in these multi-million dollar issues. The other problem is, is that we talk regularly epa regulates your outdoor air.

They do not regulate your indoor air. They are not in your homes, whether you think that or not they don't care what you breathe right. They care about what's outside and what's outside, comes inside, and what we're really understanding now is in the building. Science side is what comes in sticks to everything inside and it doesn't leave so think of your homes as a sponge.

All of your surface areas, the floors, your carpeting, your walls, everything all of this stuff sticks to it until something says. Ah, you know what you need to leave this and go do something else that it moves around and ultimately we're breathing it. But we now understand that homes are a sponge and we are dealing with why our indoor is much worse than outside. Nobody says: oh three, to five times: no, it's hundreds of times, sometimes worse than outside.

Unless you live in pittsburgh, that's right! Yeah! That's! That's! Gets a great f from the american lung association for outdoor air, but those those things in the outdoor air do come inside and do concentrate the particulates guesses from outside, as well as radon coming up. Would you recommend the home chem yeah if you're looking for some great information about what's really going on with the chemicals inside and outside, especially inside you can go to search home kim and they actually took a house down in austin and they spent millions of dollars And they said: okay, your university you're just going to study the particulars that come off from cooking you're, going to study what happens with people clean and you're going to study. What are the materials that are in there and you guys all work together and they're finding out that strange stuff happens while you're cooking or you cleaned earlier or just in general, your ozone and the light comes in, and your cleaning products turn into new different chemicals. That stuff we never could fathom, they are now trying to still uh explain all that.

They explain why thanksgiving meals, one of the hazardous times of your life, when all your family around and you've got all these uh. You know toxic stuff that you want to eat. In a couple hours, you definitely need to look that stuff up go ahead, so these are some things that are outside we're like oh yeah, the air and don't say fresh air. You can explain to your clients, fresh air, but in general it's not only fresh somebody's burning leaves or doing whatever you live near some nasty place and ain't always fresh, so it's just outside fresher, maybe yeah right yeah.

So these are all these are outside and again, homes are sponges and i tried to change the word from air leakage infiltration, it's kind of a weird word. You can use it, industry uses it, but it means energy and the fact that you're five dollars uh a month, that's doing from your meter. It doesn't really impact your oc. Your your your clients, they're, like yeah great thanks, a lot buddy for saving me five bucks, but if you could save stuff that prevents actually days off work, their kids, getting asthma attacks or doing a variety of stuff that actually brings the meat to the potatoes.

They actually want to listen to you and willing to pay an extra 800 to upgrade their filtration system or more so air leakage is a contaminant or exposure pathway, stop using air leakage as an energy penalty. That's a minor issue. So all these things happen to the house they're all coming inside and the one thing that i tried been promoting is that we have allergy seasons. You guys are familiar with allergies, allergy series and alder season, but what we're not admitting yet - and we haven't identified wildfire smoke season - you guys are probably the only part of the country where you're not really getting it.

But if you live anywhere kind of north wild. Even though it's from california it impacted canada and impacted new york and all these upper states, they now have wildfire season and they don't have wildfires. So this is something that's happening regularly. So i forget is that's the swiss cheese or the sponge.

That's the sponge. Okay! Thank you. That's right. I get the two things yeah, the the swiss cheese is the uh access to allow stuff in so once stuff's.

In now, we've got all this stuff in here, so uh, you're, cooking, you're, cleaning, your vacuuming and all this kind of stuff, and then the really the major issues is people get out of your house. Don't come back, your house would be great, but instead so we live in the house, so it is a significant challenge for you as a contractor to be like yeah yeah. I can uh address your house because it's fixed, but i have no idea how many people are in here. How often you're in here and now you've got seven cats and three dogs yeah.

That's really going to make your particulates go. High. Carbon dioxide goes high. All these things, so the people are the problems so get people out of the house and they'll work much better.

You made a comment online, the other day about the knee biters d-biters yeah, causing a high co2 level. Oh yeah yeah and yeah yeah you're uh. So people were like: oh, i got a high co2, i'm like how many dogs and cats do you have because they breathe much more than we do and i had respiration yeah. I had monitors and i couldn't figure out why, at four in the morning my monitors went, and so i realized that i was up at four in the morning and i realized my dogs were sleeping they're like yeah they've got the living room and they hang out Right next to the monitor, so that was the reason so yeah, so we're going to go through a few things here.

You know um does the air you breathe come from? Where does it come from right because we think of that as like? Oh yeah? Well, it's just outside air, but it takes some path to get into your house i'll, set up a prop later over at the accutools tool showing how we actually breathe through that. So one of the things that we think about is is uh hot always goes to cold. Your uh beer does not get cold in the refrigerator all right, the heat is removed. You guys.

Clearly, this is your concept. This is what you guys live and die by. So you know, but people say: oh yeah, i'm gon na cool, your air. You could say that to an occupant, but if you say that around us we're like, i think you need to go back to your science.

You go back to school because we know that's not how it works right. So here's your example of that you know the can goes in and all the heat is extracted. So here's what's really happening, though, as we're depending on the season is that you've got heat. That's either hot to cold, and if you have air leakage that goes along with this you're taking all along all of the stuff with it.

Okay. So if i've got hot air trying to find its way in the the temperature moves by itself and hot air can even move more and bring more particulates with it. So you can see the difference of what's happening between the summer and the winter here, and these guiding principles of the icon in the upper right hand corner are part of the hayward score. You want to talk about that used to work for hayward yeah, so i just uh, as you probably caught from jim or heard the word on the street.

So i was a healthy building scientist and now i decided that i needed to be more active in people's lives in terms of what you do and helping you do that. So i was in favor of score. It's a phenomenal resource about trying to improve how you lived your life, but we just weren't engaged in people and we really weren't getting stuff done so i'm like i need to go so i've been talking with jim for years. So that's why i'm here um! In fact, i firmly believe that's why i switched that the number one the number one contractor that can change the occupants lives on your first visit is you you can upgrade their filtration system in a blink and change their entire way.

They live in the house. Low flow, low, static, great filtration system is the ultimate thing you can do. You can hear lots of crap about or lots of stuff pardon me, you know pco and uv, and all that stuff filtration is huge. You could do that day, one.

So i'm like. I need to get in there and start working with people about why this message needs to get heard. Hayward score promoted that, but we weren't doing it so you're familiar with uh uh airflow. These are some of the challenges you have with radon right.

Okay, so we have stack and wind effect, the the stack effect is that there's a chimney there's a stack effect happening right now, where air is able to get in and move up and trying to find a way through here, the higher the building, the more prevalent It is, and when these things we can't control all right, wind is just constant. It's constantly moving across uh, it's actually impacting so one side has actually got pressure on it. The other side's got uh opposite pressure, so, depending where you're in the house, it's actually making pressures all the time that again, are actually impacting how your clients are responding to comfort and how the equipment performs and there's there's a concept called the neutral pressure plane, which Both the energy, conservatory and retrotech have good training materials on joe also used to be with retro tech uh. But but that's a really important concept to drive home when you're, trying to understand how air conditioning systems work in a house that that pressure plane and how they can be these driving forces that we talked about starting off.

So on this example. We use this because it's darker so on this example over here this doesn't know, does so at the bottom area, where the uh the floor are the people standing. That area has a lot of pressure. That's coming in all right at the top's got a lot of pressure coming out, but at that second floor, that's actually this neutral area between the two of them, where you don't have a lot of infiltration or contaminant pathways right.

So you got to focus on where the air can move in and how it gets out. So if you really want to control there's areas you guys can focus on, i don't need to seal the entire wall. I need to focus on the bottom and the top to make sure i'm not allowing the chimney effect to actually happen. So insulation can or cannot be an air barrier, i'm sure you've.

Sometimes the people call filter glass. It ends up being a filter when there's enough of an air gap that the insulation is not having any impact because there's air moving through it. You need to have the insulating area, the insulation up against the air barrier in order for it to be effective and they have those sale cells sealed together. So it's it can be done poorly or can be done professionally.

So in theory, insulation is not an air barrier because it allows air to move through unless you have rigid foam or something that is both okay. So that's really the concept, but we use these same. You know things we use in the attic, because insulation are actually the filters, those rock rock grabbers that you have in your hvac system. Hopefully, if you have them, you've got some other supplemental filtration that actually is effective for the house.

So here's a good example yeah go ahead, so here's a good example that we have uh, you know it's cold outside and somebody's got a sweater on, and they're freezing and the other person's got the same thickness of a layer, but it actually has got an air Resistant layer with a little bit of thermal and they need to be connected all right. So if you see the example here, i'll use, a laser pointer is the pink is your insulation and the blue is an air barrier. Okay, the air barrier goes anywhere until there's a hole right. Every time you see a receptacle, that's a whole air barrier has been compromised.

All right can lights. All of your duct penetrations are a compromise of the air barrier, so you follow the ceiling or if it will assume that your air handler and your distribution is in the attic, you follow, your air bury the drywall, and then you put a hole in it. Next towards the air barrier go. Ah, it's following the ducts up into the system: that's the next air barrier! So if you have duct leakage, you are leaking to the outside, so think of your system as the next level of air barrier to what's actually getting exposed to the house and contaminants.

In fact, you're in the attic. You have a really good chance of bringing something into the house just because you're actually putting potentially negative pressures up there. One of the houses i lived in, they typically have panned returns and it wasn't. It was a nice house, it had a high and a low return in the wall.

You know that kind of classic building structure, uh and at one time i brought him with thermal imager, and the bedroom was always a little bit hotter when it was. It was cooling season and there was a maybe half inch diameter hole where a wire had run through that ran into the pan return. So i was essentially pulling load from the attic continuously and i could see this nice stripe in a thermal image of red and orange coming down the wall in the bedroom radiating heat, i had allison bells, who came here last year, helping with the calculation. It was something like a quarter: ton of cooling load was added from that small hole it, but there's only one hole, only one hole just the one hole, but the home has probably got no.

There were 15 holes, but just this one was about a quarter. Ton of cooling, the physics is just mind-blowing, but we're also assuming that all of that framing those two by fours that are toenail between one and the other that are creating your ductwork are really airtight. So there's lots of issues. I have panned ducts myself, i'm trying to figure out a way around it.

So yeah, okay, oh you got it all right. So, let's go through the concept here, i'll use that yeah. So we actually have an attic. That's ventilated, very common, to have an attic.

That's ventilated, the green is actually air that we use to ventilate the attic okay, so it's coming in and then just as we mentioned, we might have holes or other issues here that are dealing with either it could be wiring. It could be drywall. You can see that i got these holes that are allowing air to move up and down whatever goes again. It's you know more to less so more moisture goes to less moisture.

Hot air goes to cooler air, so wherever it is, it wants to move no matter. What it doesn't need a pressure to actually move some of that stuff. Normally, we actually have pressures that we're adding to our house and you guys, install or maintain to do that. There's also this sliver across all of your drywall, where it goes all the way up to the attic up in there is you're like.

Oh, that's, not a lot, but you think about all of the square footage around all of your. You know. Your rooms adds up to be a lot. It's a significant amount of air leakage, it's right down on the edge of the drywall, coming right down your walls and causing issues that are actually end up as a thermal challenge in the room, you're trying to condition all right.

So it looks like this. Your top plates all right, big holes. It should look like that, and actually i should correct that. That is not your best way.

You want to use some type of long, longevity of caulk or just fill the whole thing with foam, but this toothpaste approach isn't the best. We know now that that actually air leaks. This is an older slide and actually it's some still air, like it's a not airtight uh, a good mastic, you guys remember mastic, is actually the best. I use the you know your uh, the the the yeah, the mastic, with actually the the fiber.

Thank you right here we go yeah, then the fiber tape fiber tape with the mask together. So all right, so we're back. Let's watch this move down, so somehow i've got stuff in the attic. It's moving down my walls.

I can see what's happening somehow it's actually going to get down to the first floor and even the second floor, so we're watching the path come all the way down the wall and i'm wondering how does that actually get all the way to my kitchen right? What's causing that air from the outside to the attic to get all the way down, anybody see it in the picture. What's causing that the hood? That's right, so you turn your hood on air goes out. Air. Must everybody come on this area? Air goes out error.

All right great, so i'm taking out 100 200 300 400 cfm. That much is coming in. So it's like. Oh here's, a nice, simple path, i'll follow over here here and there and next thing you know, you're, taking the air from the attic down to your kitchen.

All right, uh, there's other places where you see this show up these bottom plates are actually a notorious. You know, and they put this uh seam sealer there. That's actually not an air sealer, that's for moisture and other bugs and other stuff. So it's not really designed to make an air uh seal tight across that bottom.

So i now got air finding its way coming in and you can see what's happening, uh and there's a variety of stuff throughout the house, not just your heating and cooling system, but even the fact that i got heater and dryer or the dryer that's down there. The dryer is a massive uh. Let's see here, anybody want to guess how much cfm a dryer moves. There's some guts over here group over here give me a number yeah.

Four hundred four hundred, i got four hundred four hundred going. Two two three hundred four hundred got six hundred: let's go back downtown, no, no! No! No 200 sold 200 cfm per what per minute 200 feet per minute per minute. We could yeah, we do math 1200 square foot uh, you know most of the house in an hour for those of you that are doing your. How long do you guys run your dryer 60 minutes? Anybody else turn the knob all the way on.

If you're, not answering your wife, does your laundry okay? That's the problem here? Okay, so she knows, and she knows you don't need to do 60 minutes. Okay, but, however long it's on that amount of air is coming in. So, if you're really comfortable on a cold day or a hot day on saturday and you're doing what you want to do, or on sunday and you're like yeah, it's really not that comfortable, because she's doing what she's doing your laundry and drying all day taking air Out and bringing hot or cold air in right, so try and do your laundry convincing you got ta go home and convince your your your spouse, your better half! You know what you can't join the dryer during the day. Okay, you should run it when we're not home or at night or early in the morning, or something i'm sure you'll be successful, converting how you condition your air with the dryer.

So if you are able to control some of these things, you'll find out that you're. Now, in control of these things, and ironically, there's a system similar to the the dryer, that's a heating and cooling system. So if you have superior leakage, you probably not have much of an issue, but if you don't you're in the same stuff so similar to the thermal thermal, that's right, water, moisture! Yes, some of you may be familiar with this concept has been around for a long time. That is, that diffusion.

If you're not going to diffusion diffusion, is the amount of moisture that literally moves through materials like rubber is almost impenetrable. Metal is impenetrable, but like drywall or other surfaces they allow moisture to move through. Okay, it's just what happens, uh more moisture on one side, less moisture, it's coming through the material. It just seems how long it is.

What's this perm rating right, so drywall has a specific perm rating all right, so this one you can see on the one side, here's our pointer here on the left right. This one has no hole. It's just a painted piece of drywall, one of them. You probably got 50 or 60 of them in your house.

This one's just got a one inch hole, just a one inch hole all right and the amount of moisture that moves through that over a heating season is around 30 quarts of water right. So it's a lot of moisture. If you do this in your climate, you're dealing with gallons per day, all right, it's a huge amount of moisture. But it's again, it's just one small hole.

Most homes have how much of a hole you're, probably around three square feet of an average leaking of a house, but let's try and see if we can't make this actually visualize itself so again on the left was solid on the right is a hole they both Have diffusion so they both have the same amount that moves through them. The one with the hole has a whole lot more moisture, that's moving through. Let's just add it up so clearly, you know we have one quart of water showing up and uh for one hole, and then you can see that how much i'm filling up a joist space visually, what happens over the course of a heating season? That is an enormous amount of air leakage, so this is a mixed climate. You guys are a high moisture climate, so it's even more so i've got 30 quarts uh or for those of you that are metric, it's 28 liters.

I know you're curious about that. So yeah all right - oh i got it should give you a better slide. Okay, so we're going to do a quick quiz. Okay, the answers are on there.

So don't look at that. Don't look over there. Don't don't look that'll! Give me all right. So how much does the bath fan move all right or it could be what what in general now, the 50's minimum you're, probably getting 75, maybe up to 100.

if you've got 150. You've got a big bathroom and people with a lot of money uh. How about the your average range? What do you guys know about an average range? How many people put in more of 400 who's? Putting a range in is more than 400 yeah. There's one over here right, you've got to watch small kids and animals can leave these things.

1200 square foot is not uncommon. Uh cfm, for for one of these things, okay, downdrafts. These are the jen air all right, and then you got these emerald hoods. Those are the ones that suck all that all of that, and then we got our dryer down at the bottom and your air handler.

It doesn't leak so we're okay, but this is the amount of cfm that's moving in and out all the time, and you only have one bathroom right: one bathroom fan and only one runner at one time, plus the dryer plus cooking. So you can see all the cfm's that are leaving the house that have to come back in all right. I like to visualize stuff, let's visualize this the concept. So this is a bath fan and a kitchen for just 20 minutes all right.

Yeah 20 minute run time. This is the volume i want to visualize the volume that we have, that must leave and come in, and it clearly doesn't just come through the wall. Like i showed you here, it's actually coming through all the penetrations that we've shown you in the previous slide, so this amount of air leaves and must come in when you run your bath fan for 20 minutes or your range hood. This is a low range.

So it's only 100 cfm small bath fan too, so you can visualize what's happening in terms of the amount of air, that's moved and uh, so the air that's coming in. It's really nice condition clean air. It's filtered everything's good to go! We're temperature controlled right, yeah! We're, okay, all right! How about that dryer? Let's do the dryer thing so this is. I had to turn the house sideways to show you the amount of air that your dryer moves for just 60 minutes, okay, so for those either doing the 60 minute dryer.

This is what's going on, so you imagine why you're getting uncomfortable, because you're drying your clothes, enjoying your beer watching the game and you're, realizing that i know i'm getting colder or hotter. So you can see it's a huge volume and we only do one load a week right, yeah, okay, what's oh, we did this already, so the bulk moisture, i'm gon na skip past bulk moisture. So what happens, though, is one of things you realize in moisture? If you guys live in the moisture climate, we have moisture everywhere, i'm lucky i finally moved to denver. I lived in arizona where we're like moisture those things just are not a challenge for us, so the moisture is getting in as we try it below, but here's what happens when actually it comes in is that and we're going to combine it with air infiltration.

So air is green. Moisture is blue, you're going to watch things, go in and go up and find the path out. This is just how nature works is how it's working all the time. It's going all the way up and it stopped on the right side.

It did not stop on the left and the difference is because those of you that think that adding that super thick spray foam is awesome. Well, it has its issues, because what happens is that when the moisture is moving up, it says. Ah, i will stop here because i really am struggling to move through, but it will move through. Those are not one unless you do a great job of making sure it's all super tight, no gaps between any of your framing.

It will prevent that moisture. But the challenge is that what happens? Is that it doesn't? There are all these little gaps, so it's about a 20 year issue that you'll happen that you watch your roof rot out over 20 to 30 years, because you let moisture move through. On the other side, the moisture gets through to the roof deck yeah. It gets through the roof deck and has nowhere to go except the roof deck.

So it's like okay i'll, stop next level task to have duct leakage, but it is without question the most common thing that happens: uh it happens at the air handler, which is your greatest leakage. It's happened in other places and you know i've done home inspections, where i got shocked at some of things that i would find in some of these issues. But i want to make sure you understand the impact that it has on the actual envelope and on the people itself. So we think a lot of ducklings.

I mean they're, not getting the air, they want it or i bring in some hot or cold air. But you actually impact the pressures in the house okay, so this is supply, leakage supply leakage sucks and he really sucks because they both start with s, supply and suck. They go together. Okay, and what it's doing is it's sucking on the envelope.

So it says: okay, we'll just say that these are 500 small cfm five we're called a thousand all together 500, i'm losing i'm losing 500. going to the attic going. The crawl space went somewhere, but my motor says. Ah i'm pulling a thousand.

Give me 500 from some place, so it says ah i'll find some leakage in your house, and i will replace that 500 from anywhere. I can path of least resistance, so supply leakage. Does that okay you'll find out that this may actually be better, even though it's worse for the for what you're doing so, i'm now creating this uh pressure uh on the house, it's negative pressure so like well, let's do the opposite, so i got ta return so Instead, i got a return like so i'm going to bring extra pressure in right, and many of you feel that more people have returned leakage than supply. I kind of agree with that be like oh yeah.

Return is not that big of a deal, but here we're actually putting a positive pressure on the house which in general i would rather have than the other one. But here's what happens you go out to a house and you find one of these huge leaks. You seal it you're, like god, damn who the hell. What idiot did this and you find out later it was.

You know it was you 17 years ago, all right you're, like oh man, it's been a bad day, so uh you fix it. So, instead of having dominant return leakage, what do i have now returns fix? What's the next one, we're back to supply right? So, let's go back to supply for just a second all right, so supply saying i'm going to grab air from outside. I have a hot water tank. That's in somewhere, that's connected to this negative pressure.

What's the greatest path of least resistance in this house now the water tank that just vents straight up it doesn't have to go through a window and around this or through a crawl space. That says i'm going to come back in so you fix your return leakage. Only to realize you just compromised their safety by actually increasing their supply leakage and now they're back drafting on their hot water tank. Never thought you! You would have never connected these two things.

Next, you know they got carbon dioxide, carbon dioxide alarms, going off, you're like what the hell is going on. Your house is so messed up right. If you need to fix everything at once, you can't assume that one will lead you to the path of solving the rest of it. We talked a lot about the movement of heat air and moisture through the enclosure and knowing about the barriers to that and controlling that so blower door testing you're going to hear a lot about that uh this week.

If you haven't heard it already, that's a very important key to determining how much air leakage you have and then using the blower door as a tool to find that leakage to seal the leakage and to get control over the air uh. In fact, you can use your blower door to determine if your ducts are leaking. It's a real, simple path, go ahead, so you got your blower door going right, we'll just stay at our house and blower door is going. So i usually i'm depressurizing this one way.

Remember we talked about the ducts, so the ducts are now the air barrier, so i can go around with this little pan in my gauge to be like hey what kind of pressures do i have so i've got a receptacle. I can put my little pan over and says: oh i've got uh readings here that must be going to the outside. I can put it over a variety of stuff can light so that can light's connected to the outside because of the pressures i'm getting similar to the blower door. Put it over my ducts and realize that holy cow i've got, you know three or four pascals.

That means it must be connected outside i'm bringing outside air in while the blower door is taking stuff out. So it's a real, simple way of doing diagnostics. Oh we're in florida right. I actually trained over 300 hvc contractors with fraca a couple years ago, because you guys are now potentially had to install an exhaust fan.

If your blower door became less than three year changes per hour, ventilation, literally yeah ventilation, yeah, it did do a uh, a whole house ventilation system. What do you think the number one question i got from a group like this number one? I mean it happened every time uh can i just put more holes in the wall, or can i just put a vent that just goes through the wall so that we won't be below three air changes when the guy does the blower door it'll be like 3.2 Or something - and i don't have to put the fan in it - it was stunning, it was a common question like can i just drill more holes in the top plate so that we won't actually reach that number? It was stunning i was. I couldn't believe it not like one guy. It was really the most common question.

So i think, if i add that to the slide, don't cut more holes just to get your number lower. Oh wait, but i did tell them to get a blower or at least have a pressure pan, because most guys that do a blower door don't have a pressure pan. So when they're like oh the system's failing and it's your fault, it could be the electrician. It could be a lot of people go over there with the pressure pan and be like, let's find out, because i sealed my stuff.

I sealed around all of my openings and if you had a pressure pan, you could either learn that you did fail or learn that you're, not the problem go call somebody else with a simple pressure pan, while the guy's doing a blower door, you could determine that You're not the problem see you later, but i came back to confirm that so the two world leading companies that make blower doors and duct leakage testers, are both here. Energy conservatory over here retrotech over here, go by and ask them to see to learn more about this, how you use a pressure pan, along with their gauges. It's pressure. Testing is a tremendously revealing tool to tell you about these problems with uh errors, because it's not just your ducts.

It's also where you didn't seal around your ducts right and hopefully you're familiar with the blower door test, as illustrated in this little image here. But basically, you replace a door with a air air barrier cloth with a fan in it, and then you control the fan to take the house down to a certain pressure level, and then you measure the amount of air going through that. So you you basically sum up the air infiltration leakage under a test pressure on the house somewhere, i'm measuring the flow in your uh air handler yeah, and this is what a blower door kit looks like um. If you're not familiar again, it's it's a large fan, but it's not just any fan.

It's a fan that can be controlled can be ramped through various speeds. Uh has different orifice plates in it, so you can control the amount of air. It's it's a really. It's a it's like using your digital gauges on an air conditioning system.

You got to use this kind of digital gauge on a house to really tell what's going on with airflow um, but it also is going to determine if you have connections or areas where you're trying to like reduce so i'm like. Oh, i can actually tell my attic is majorly connected to the inside of my house or my crawl space, which means when my air handler runs. This stuff is causing those things to connect um, and you can also determine other things with it as to what's going on with any place where it's connected, specifically the garage, the garage is the most awful place. Besides the kitchen kitchen's number, one garage is number two they're just horrific.

We should never have them in our house, and the pressure pan is pretty simple device. Basically, you have the suspected area, you seal it and you have a hood that goes over it connected to a digital gauge. That tells you what the pressure is on the other side of that that device. So you can determine the amount of leakage, the not the amount of leakage, but the kind of the percentage of products and where you can, you can actually track it down.

As you know, what this is an area, i need to focus on wait. Wait, wait, pause. How many people work with somebody that does air sealing? How many of you are doing a whole house system like i do this, but i work with somebody that does that anybody here have a energy group that they work with. If you want to triple how much money you make off somebody else doing work, that's your relationship! You should set up because they're all over the place uh and they they they're the ones - are going to crawl all over and fix those problems, and you just make money off the referral.

I'm telling you it's one one way to expand what you guys are doing so so uh hers, raiders, building performance contractors right. Well, it's actually a lot of insulation. Installers. Now that's their goal.

Is they want to be able to control the envelope, so they do air sealing now as part of that package, so that's a great relationship and then a blower door test. You can use infrared imaging if you do it at the right time of the day. You have the right kind of conditions, you can walk around and you can actually see these temperature stripes in the wall, which will give you an idea of any of the sort of the attic penetrations or any other um outlets. Exterior wall outlets.

That kind of thing yeah sam's got some good videos. I don't know if tec does sam's got some good videos on this, but you want to do a first scan to find out where my installation is missing. Like oh, okay now turn the blower door on and you're like holy cow. This is a major air problem that i'm having right here right time of day, though, is important to do that testing, because the sun's going to mess you up, you have to do it early in the day or at least track where the sun is keep good Notes there are various standards um, so the air changes per hour at 50 pascals, that's sort of a bulk measurement to be able to sort of grade and compare different buildings.

Uh a passive house explain what air changes is sure. Air changes would be taking the total volume of the house and the amount of cubic feet, that's inside the house, and then how much of that moves in an hour. So how much of the air in the house are you replacing with the leakage? The ach 50 means it's a test being done at 50 pescal, so the test pressure. So you need to sort of put the house under a test pressure in order to make this consistent reading.

You can't just let it be what it is. There's natural, but you want to do it under a specific test. So you can. You can have this number of comparison, so i'll be talking tomorrow about the house that i built and we'll talk a little bit about what passive house, with the whole definition of the basic definition of passive house standards, but they're.

Looking for 0.6 air changes an hour, the iecc, the international energy conservation code was looking for seven um 2009 right. Many states have moved to five air changes per hour, as you can see it's starting to get tighter and tighter 3.5 excuse me: three is the 2018 iecc and the icc isn't necessarily adopted by every authority having jurisdiction uh. They may change and are very different parts of it. What's the icc, oh international energy conservation code and the house that i built, i went for one air change per hour at the test pressure of 50 pascals when you get down to those lower levels, even blows.

It like three, you need to look, you can imagine if your home is super tight, like you can imagine, you know, closing off any of your events in one of your small rooms or your bathroom and being in there for a long time right and then add Your dog or something right. What do you think's the number one issue you're going to probably come across pretty quickly? What's what what's probably going to increase uh co2? Thank you yeah. So i now got all this and uh uh, i'm now struggling to breathe. So when you get a tight home even below three, what is a good ventilation strategy briefly, what's a good blemishes strategy, xavier you're in the room, speak up? What's a good ventilation strategy, balance ventilation, what's balance mean? Ah, okay, that's right! So he's saying i don't want to just use exhaust to like just bring stuff out because it's bringing crap in through wherever you don't know where it's coming.

I don't know where it's out of control right. So i want something that says i will take some stuff out and i will bring stuff in at the same time also allows a neutral pressure plane in the house, controls the environment and you can do balance ventilation here. I know it's a myth, but you can do it. You probably need dehumidification.

You need to talk to nikki over there at santa fe, but those two things work well together. So if you're really going to get tight and you're just uh relying on exhaust ventilation, your people will be uncomfortable right and it's not just a temperature. Uncomfortable breathing is uncomfortable people say i'm uncomfortable, it isn't just temperature anymore. It's because i don't like that room.

Something's going on in that room, they don't feel comfortable in means uncomfortable and a good catch phrase to keep in mind if you haven't heard already built. If you build it tight, you got to ventilate it right yeah. This is what it's a stupid phrase i'll correct. You good so ventilate it right means you do do something.

That's a strategy. An exhaust fan, i mean a fart fan, is not a strategy so quit thinking that oh, we met ashrae 622 because we put an exhaust fan. That runs all the time at 20. Cfm, really, that's that's doing nothing for what you think about is making your occupants.

You know comfortable and healthy, so option two offer it. They don't want it. You least put it on the table. So when they come back later, balance spend like balanced ventilation or they talk about yeah.

No, this isn't working or you know my kids asthma keeps acting up like oh yeah. Well, we suggested this okay. Now it costs three times as much. To put it in.

I got to watch our time here. So caleb's got us okay, he does okay yeah. So a properly sealed house is more comfortable. Has reduced energy costs, has better indoor air quality and makes your hvac system work really well yeah.

It does. I mean it provides uh. Perhaps a lower load and again i'll talk about tomorrow, how i have a 4 400 square foot house running on two tons: air source heat pump for heating and cooling and how that can be achieved? If you can pay attention, you can move in that direction. If you pay attention to these kind of details, so pressure and thermal boundaries should be continuous, as we mentioned before, the air is kind of the one one of the things you have to pay a lot of attention to that's.

Why we talk a lot about blower door testing air leakage requires a hole and a pressure difference so, as joe is shown with the supply and the return leakage, natural forces, other other stack effect can cause air to flow where you might not think it could be Flowing duck, location and condition can cause room and pressure imbalances that goes back to the balance, ventilation concept that dave raised his hand and mentioned, and the blower door is the device you use for quantifying the air leakage. Thank you for reading that slide. I know i know, isn't it awesome that i can do that you did without my glasses on yeah they're on your head. Just you know, okay right, we do need to uh exit the stage here pretty quickly, but i want to thank you for listening uh joe joe is my reference and resource find a good reference, and resource uh bill is also my reference and resource.

That's right for different things, so you can get in touch with us through. These email addresses joe measure quick bill of true tech tools. Thanks for watching this video again to find out everything we have going on, you can download the free hvac school app on android or on iphone or go to hvacrschool.com and then, specifically up in the top you'll, see events to find out more about upcoming symposiums hope To see you there, thanks for watching our video, if you enjoyed it and got something out of it, if you wouldn't mind hitting the thumbs up button to like the video subscribe to the channel and click, the notifications bell to be notified when new videos come out, Hvac school is far more than a youtube channel. You can find out more by going to hvacrschool.com, which is our website and hub for all of our content, including tech tips, videos, podcasts and so much more.

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