- [Narrator] Coming up on Home Diagnosis.

- [Grace] You probably had heard of energy efficiency, going green, those goals only tell part of the story.

- [Corbett] What if we do such a good job air sealing that we make it 'too tight?'

- Our mantra is: make it tight, ventilate it right.

- There's only one place as far as I know, in the world, where you will find this.

- [Wade] Any home performance contractor is going to want to be able to figure out what is behind the wall.

Before this system explodes, I'm going to go ahead and fix it.

- Home Diagnosis is made possible by support from the Alfred P. Sloan Foundation, by Fantech, 'Breathe easy', by Broan-NuTone, 'Come home to fresh air', by AprilAire, 'Everyone deserves healthy air', by AirCycler, Retrotec, and Santa Fe Dehumidifiers, by generous support from these underwriters, and by viewers like you.

- Welcome to Home Diagnosis.

My parents like to say we make unusual choices, like living in 200 square feet with two kids and two cats.

- Or hosting a YouTube channel about home performance and building our own houses.

Home performance goals and metrics are still unusual choices, but believe it or not, the science is as old as I am.

- In today's episode, we're starting at the very beginning, how the science of homes developed, and why you don't see it on other home shows, and what you've been missing in your own home projects.

- We'll be specific so you can know the secret stuff to ask for, and learn the number one way to really be the master of your own home.

- They say home is where the heart is.

- And we certainly put our heart into building our first house.

So how hard could it be to build another one?

- I'm Grace.

- And I'm Corbett.

- In our TinyLab, we helped homeowners gain control of their homes through scientific testing.

Now, as we build our forever home, we're testing ourselves.

- Even though we know a few things about the invisible dynamics of homes.

We're teaming up with scientists and building experts to design and build a perfectly-tuned home for our family.

- The physics, chemistry and microbiology of a home might seem mysterious, but it doesn't need to be.

- While this is a personal story, full of twists and turns.

- It's also the story of the science of homes.

- Join us to unlock the mysterious science of your home, too.

For all the scientific approaches that we're trying to take with this home, we realize that it's all based on total nonsense magic mojo- because it's all based on dirt.

- And where we wanted to put our house, there was actually a foundation, so we had to tear up the foundation, and under that we found another house buried.

- We have a septic tank, which we didn't know about.

We're going to build our house right on top of this thing.

Not!

We're finding trash buried all over this property.

And that's rude.

But burying trash where somebody would want to build a house is especially not nice.

So we had to obviously take that all out.

We dug way down past where we wanted to, and so we found lots of huge rocks in the way.

So part of the house is going to be built on the rock, which is what the wise people do, right?

- Build your house upon the rock.

-So what we want to do is make sure that the house doesn't settle unevenly.

So we had to turn the rest of the dirt that was not rock into, basically, rock.

By compacting it and compacting and compacting it and only bringing in this much at a time and then compacting that.

- So we literally had three dump trucks of the old house removed and then several dump trucks of new dirt added.

And we had a geotechnical engineer come out and confirm it.

- So first day of construction on the house and we go $10,000 over budget and several weeks behind schedule.

You know when the suffering is that good, you must be on to something wonderful.

They say renovating a home is like trying to build a home, with another home in the way.

Let me introduce you to some experts at tuning the performance of older homes.

So here is a house that's about to get a performance upgrade that is funded by tax dollars.

This is a really exciting program that has helped income challenged people for decades.

Let's go see what they're about to do.

So Jesse is in charge of today's activities, and we've got holes in the wall behind us.

Can you describe what exactly we're seeing here?

- [Jesse] These holes are to dense-pack wall installation.

We'll use a chair rail to cover the holes.

- The chair rail is pretty fancy, because normally we're just patching over this stuff.

Which is why normally, this doesn't happen from the inside, unless you've got somebody who's classy who can figure out how to make it look nice.

So this is how we're going to be shooting this in here.

We're spearing this up into the wall.

We have very high tech filter fabric to keep it from jetting out of the wall at us, right?

How long does it take to do this entire house?

- If we had all the holes and everything prepped, it'd be blown in probably two hours.

- Awesome.

(drilling the wall) - There we go.

- You're in there and then you start pulling it out, you're coming along and it's filling up and you're like, Oh crap, and big ol burst if you get it right to there, you know, you can get a blow out and blow everywhere and make a mess and get in people's hair.

In reality, it's not like it's perfect every time- you're going to make a mess.

- That's why we've got the plastic.

Yep, and the dry vac to clean up.

Of course, the other main thing I■d be careful about is not blowing apart the wall.

Because there's been cases where you start blowing a wall, and if it's not strong enough, you'll start seeing the sheet rock almost starting to bounce.

You have to be careful about not ripping a whole sheetrock off the wall.

It gets scary.

- Darin and Paula, you guys have lived here for how long?

- 30 years.

- Okay, and have you done anything like this to it?

- Never.

- Never ever.

No.

They went around and identified that there is no insulation in any of the outside walls of this house.

- When I■d get dishes out of the cupboard, the dishes were always cold.

- And the walls get very, very cold in the winter.

Extremely cold.

- Have you known other people who have put their houses through this?

- Have not.

- I have not.

- Okay, cool.

Well, it's a fun experiment!

- Yeah.

So welcome to the high performance club.

- Oh, thank you.

- We're going to go see what they're doing on the outside of the house.

(drilling the wall) Do you guys ever get worried you're going to pop to the other side of the plaster?

- Every time.

(laughing) - We always worry about that.

Dense-packing cavities is a really interesting application.

It is elegant.

It is an art.

Of course, I hope you'll remember that the main ingredient of that insulation is air bubbles.

That is what really you're paying for, and that is what is going to trap the heat.

So if you imagine that we're going to shove this in here, and we're going to pack a bunch of this cellulose insulation into this wall cavity.

What we're doing, technically, is squeezing the air bubbles out, and that is reducing the insulation value of this.

But what we're getting in return, if we do it in the right ratio, is air tightness.

It's not the same as air sealing with something that's going to really stop air, it's just slowing down the air leakage enough so that we can really affect the performance of this house on just the walls alone.

So this whole injecting requires you to feel and listen and have kind of a sixth sense with what's going on in this wall cavity behind where I can't see anything.

And you want to be especially careful as they're working from outside, not to, as Zack mentioned, blow out the wall inside- that can be both messy and expensive.

So Wade, I know that your crews really know what they're doing by this point.

- They are very good.

So let's just play a little game for a second.

What if we do such a good job air sealing it that we make it 'too tight?'

- Mm-hm.

What happens at that point?

So you're going to start having VOC buildup.

You're going to have indoor air quality problems.

You're going to have moisture issues.

So we need to address ventilation.

So our mantra is: 'make it tight, ventilate it right.'

- Okay.

So now though, we've stepped out of the realm of energy efficiency and we're now gonna cost energy because we're going to plug in a ventilation system.

How has the program evolved to include performance stuff that has to do with moisture and air quality that doesn't actually save us energy at all?

- Right.

- How do you justify that to the people who fund this?

- [Wade] It's health and safety.

Yeah.

You make a house nice and energy efficient, but you can also make a house dangerous if you don't address the health and safety side of it.

We want to make it as energy efficient as possible, but it's also got to be safe.

Because, what's the good of an energy efficient home if it kills you?

- Exactly.

Okay.

You said we need to ‘ventilate right■.

What does that mean when we're talking about a program that has a very tight budget, and we want to make sure that we make sure every dollar goes as long as it can?

What are the strategies that you guys use?

- We want a known, controlled rate of ventilation.

Not wild card ventilation, which would just be opening a window or whatever.

- And this is where this gets so important.

Normal contractors should be incorporating the techniques that these guys have been using for decades, which is that you do something, and then you test.

And you make sure that you have not created side effects, which you always do.

We now know that we've predicted the side effects.

And they've started installing the ventilation system before they even know how tight they're gonna get, right?

- Yep.

- That's the best way to do it- you know exactly what the crews can do, because the crews have worked there for a little while.

If you have a lot of turnover, then you've got to constantly be training, and you don't know what kind of work they do, which is another problem we have in the construction industry in general.

But here we have a vent that's coming in from outside.

Right?

- Correct.

- And it's gonna go straight into- - Straight into the return on the furnace.

- The magic of this system is that it uses a fan that you already have in your house: the fan that's built into your furnace or air conditioner.

- The other benefit of this system is the outside air that we're bringing in is also filtered through the existing filtration system, and they've installed a really nice, highly efficient MERV 11 filtration system into this.

So the outside air coming in, is filtered and then also conditioned, assuming that the furnace is running.

- So Jordan, we're in there upgrading this home.

What is your background that brought you into performance upgrades?

- So I left the restoration business, where I used to do in-home assessments for damage, things like that- water, floods, fires.

- So what's the learning curve like?

Do you think that anybody could do this job?

- Yes and no.

It takes a lot of training.

These guys have been doing it for a while.

It can be learned, but you know, it's fun.

It's an awesome field.

I'm very new to it and I've loved it so far.

- Everything in Home Diagnosis centers on the invisible dynamics of physics and chemistry at work in your home all day, every day.

A lot of people are trained to think it's all about energy efficiency.

Here's why it's about so much more.

- We like to break home performance down into the 4-3-2-1 approach we talk so much about.

If you're a fan of this show, you know the one goal we're after is control, over the two systems: skin and circulatory.

And we use the three recommendations to get there: Air sealing, insulation, and HVAC upgrades.

- The four elements we're trying to control at the end of the day are pretty straightforward: the flow of heat, air, moisture, and toxins.

Heat is probably pretty obvious to you- it bleeds out of your home in the winter, and bleeds in during the summer.

- Airflow is a much more subtle dynamic, and it leads to pressure imbalances- especially in today's more airtight homes.

We need to be more aware of this element because it's easy to detune a home by putting in new fans or changing ducts.

And it's also simple to avoid that by testing for it.

- Moisture is a big deal, and if you don't already know, too little and we get cracks in the walls and sore sinuses.

But if we have too much, we grow green fuzz in corners and things start to disintegrate.

- And the final and most important element is air quality, which is influenced by all the other elements.

The air your family breathes at home is made of chemicals (some good for you and some toxic) and laden with lifeforms.

(again, some good and some bad for you).

- When you look at home performance using these four elements, it's clear that only two of them affect energy efficiency, and they're the two least critical ones to your family's health.

To control moisture and indoor pollution, we need machines that use energy, and that's not technically efficient.

- And as we try to make homes more energy efficient by controlling heat and air, we are absolutely causing side effects in moisture and toxins- because the home is a system.

- So the next time you■re thinking of building or doing surgery on your home, remember the 4-3-2-1 approach.

- Welcome to where today's weatherization crew gets trained.

Now, any good home performance training center will have things that look like this- props that demonstrate how construction works and how things can be fixed and tuned.

But there's only one place as far as I know, in the world, where you will find this.

This is a house that is a shape-shifter.

It can basically change its performance based on what we want to show today.

So the weatherization professionals in Utah, here at the Intermountain Weatherization Training Center, are getting to see, just like you are about to, how the invisible dynamics of home performance can be changed to make a building fail and to tune it to work properly.

Let's go inside.

- [ Wade] One of the things that any home performance contractor is going to want to be able to figure out is what is behind the wall.

Normally, you can't see into the wall because of the sheet rock.

So what we have here is the ability to look into the wall.

We can put a blank on this, so it looks like the sheet rock, basically.

And then the way you figure out what's in there is you could use an infrared camera, or you can use something as simple as this, just a coat hanger.

You would drill a hole in the wall- now, we have some holes conveniently made, so we don't have to keep drilling holes- and I can reach in here and determine depth of the wall.

I can also visually look in there and see that the cavity has no insulation.

If we had a cavity that did have insulation, I can go in with my little hook and pull it out and go, "Oh, okay.

I've got cellulose in this wall, three and a half inches deep, and now I know what kind of R-value is inside of that wall."

- In the last episode, we talked about the shape of the house making a big difference for performance.

Here is one of the features that we talked about, which is where the upper floor juts out over the lower floor.

And this can be a big problem for the performance in a home, which is why in this training center we can open this up and see what's behind it.

- You've typically got insulation, you possibly could have duct work in this area, and you can see back in there that there's no blocking.

So air can move from the cantilever back into the home and vice versa.

Whereas we want to make sure there is blocking like in this bay right here, that will stop the airflow.

- So in weatherization, we actually use this tool a lot: the blower door.

It's a fantastic way to measure a lot of things in the house.

The thing that we measure first is just how leaky the whole entire house is.

But then once we've done that, we can actually use this tool in conjunction with some other tools and we can look at different rooms in the house.

We call those 'zones.'

This is just an example where we can actually look at the pressure as it changes in each of the rooms throughout the house.

And we can see which rooms have more leakage and which have less.

- Okay.

So right now we're in your mechanical room and your mechanical room probably has one of these.

This is a water heater, what we call a 'natural draft' or 'atmospheric vented' water heater.

It has this great big draft hood on it, which is a hole.

And if everything's working right, all of the toxic flue gases will go past this hole through this pipe and to the outside.

But if things are working wrong, all the toxic flue gases will spill out of this hole into your house.

So we're gonna go ahead and test that right now and see what happens.

The way we have the house configured, the flue gases should be spilling out into the house.

So the water heater is on.

I know this is spilling because I can feel it, but since you guys on TV can't feel it, we'll go ahead and show you.

We can see all the flue gases that are coming back into the house.

And they'll continue to do that as long as I let this run.

So another way we can tell is, I can stick this piece of glass up here, and as the hot, moist flue gases hit the glass, you see the condensation building up on the glass.

We can see that condensation was built up on there from all those hot flue gases full of carbon monoxide, spilling into the house.

So the simple fix for this is to add what we call 'combustion air' to the equation.

And I can do that simply by opening this door.

And now the water heater, instead of spilling, you can see the smoke is now being sucked up and out of the flue, where it should go.

And if we put the glass back up there, we're going to see there is no condensation building up on the glass.

- So here we can see that with just a very small difference in the situation in the house, that we can make something as big as the stuff in the chimney is coming into the house versus the stuff in the chimney is going outside, happen.

And almost nothing just happened- we just opened the door.

So think about how many doors there are in your house, and all the different scenarios that you can create like this kind of a scenario.

Show us more!

- Okay.

- Your heating and cooling system creates pressure in the ductwork, and the higher that pressure, it becomes a problem.

We call it 'high static pressure,' and if you get extremely high static pressure on a system, that can start to cause issues with the efficiency and airflow.

So right now, I've got the system running.

We've got our measurements for static pressure here, and what I'm going to do is simply simulate a clogged-up filter, and we're going to watch that static pressure start to rise up.

Okay, you can see my static pressure, or my blood pressure, is starting to skyrocket.

You can hear the blower motor is working much harder, which is not good.

It's consuming much more electricity as our static pressure is getting into a very scary zone where it can actually cause damage to the system.

(motor blowing) So before the system explodes, I'm gonna go ahead and fix that.

(motor blowing) You can hear the blower motor ramp down and you can see the static pressure start to come back down.

- So the high pressure that you just created by simulating a clogged filter, which a lot of us have, you can actually hear that, if I'm correct, if your furnace in the basement goes WHAM, when it starts up.

That is the sound of your ductwork deforming to try and deal with the fact that it's now being sucked on by this giant fan.

- Absolutely.

- So this is a problem that plagues lots of houses, I've found- have you found the same thing?

- We find it all the time.

- I would say about 90% of the places I've tested, it's obvious that no one has tested this before.

So this is always something that I'm trying to, and Wade is trying to, get every contractor to just test.

Just to know- if it's high, you should know it.

So as far as the airflow goes, what else can ducts being badly designed, or badly installed, or being clogged, what can that do to the house?

Can we affect the pressures in the rest of the house?

- Yes, absolutely.

We can cause all kinds of weird pressure imbalances in the house.

- Which is why we have a control panel.

- That's right.

Will you show us your control panel?

- So we can control the dynamics of the house.

We can cause high static pressure.

We can cause weird pressure imbalances in the house.

We can make things bad and then make them better again.

That way, our technicians can actually see the problems.

So we do this all hands-on and very visual, because it's super hard to believe in something you can't see.

With this, and all the other goodies we have in the house, we can show it to you.

- One way Home Diagnosis aims to change your relationship with home improvements and construction is by giving you new language to describe what you want from your home.

Most people are already trained to try and save money or time by making improvements quick and inexpensive, and to shop for home size, or amenities, or location.

- But whether you're building, buying, or improving a home, you can ask for performance.

Look- being able to prove how healthy or comfortable your family will be in your home, and predict how durable and low maintenance it will be in the long run, is totally possible with today's test tools and techniques.

- Your job is to be as specific as you can about your performance goals, so that the contractors you hire have targets they're aiming for.

If you don't have a target clear in your head, and spelled out in the contract, how can you know when the job is done?

- For example, making a home air tight is the number one way to achieve more control over performance.

Know what blower door number you're after.

If you want to future-proof your home, the magic blower door metric is three air changes at 50 pascals.

You don't have to know exactly how that's calculated, but it's a specific goal that's measurable.

And that's the secret.

- If you're aiming for comfort control, aim for all the rooms in your home to be within three degrees of your thermostat set point.

If you want proof of quality installation of your new furnace, aim for airflow out of each duct tested within 5% of what was designed in the computer's heat load calculation.

- Some contractors will run away if you ask for targets like these, and that's good- they're not for you.

There are absolutely building professionals out there who can and do deliver measured performance using testing.

And they'll be happy that you value it enough to tell them exactly what you want.

- When we first got this property, which we love, it had a giant workshop on it, which had started out in the 1930s as a stable and then became a blacksmith shop, and then became a junk shop where they basically just kept all the stuff that they didn't want to have to look at anymore.

So when we got here, of course, it's an existing building, it's about to go through another renovation that's going to change the purpose of it.

It was clad in rotting plywood and sheet metal.

The skin of a building, as you know, is very important to us.

So what we did behind us is to re-skin it, had good bones.

We put translucent skin on it, so it allows light in.

And we also took all the junk out from inside because the space inside of this has become critical for our build.

We need to be able to keep things in there to be able to make up for my lack of scheduling know-how, because I just need to get things and then I'll use them whenever.

Over here, there was a speed boat.

Inside, there was a Cadillac on all four flat tires that we had to drag out and up the hill.

And we spent a long time smashing the pianos and the guitars that were rotting inside, that needed to be put into piles to be taken away.

I could not watch that part.

So let me take you inside and show you what it looks like now.

(sliding door opening) As you can see, beautiful light in here- we do some filmmaking in this space as well.

And obviously, we're using it to keep quite a bit of the building materials.

But the lighting that was here when we arrived was fluorescent lights- which is more energy efficient than some other kinds.

But what is more energy efficient than fluorescent lighting- no lighting at all.

We ripped out all of the lighting because number one, when it's day time, both the walls and the roof are translucent and it's going to be well lit.

And also, when it gets dark at night, my goal is to be at home hanging out with my family.

Now that being said, this is an outdoor workshop, meaning it's going to be moist in here, humid, it's warm right now, the sun is out.

I have an uncle who has an outdoor workshop.

And his tools tend to rust over time.

My dad has a woodworking workshop that is totally indoors and it's air-conditioned and heated, and it's dust-controlled.

And I didn't really want be that crazy with my first workshop, so we decided to build this room behind me, which we call the Dry Vault.

It's the world's highest performance tool shed, And you'll see that it is super airtight and insulated, and it's not air-conditioned and heated.

We have a very simple machine that controls this.

Now, listen to how airtight this is.

(air blowing) Perfect.

So the control we get over this space is: Number one, it's not going to get outdoor dust coming in here a lot.

That's one of the benefits of having an airtight space.

Number two, it's insulated at the roof and the walls, but the slab is not insulated.

This is the same slab that's outside, so this space is always going to be about 60 degrees, which is nice.

But even if it does get colder or warmer, it's okay because we have a dehumidifier that runs all the time, that keeps this space at the humidity levels that we want.

Therefore, it doesn't matter how hot or cold it gets as long as it's dry.

All of our tools that we use for the diagnostics, and our film equipment that we use for the YouTube channel will not rust out and rot.

This is our concept of marrying the energy efficient space with the high performance space, and getting something that really achieves the goals you're after.

- On Home Diagnosis, you won't hear us talking much about energy efficiency, but we do know a couple of secrets about it.

Want to know the secret to powering my TinyLab?

Here it is.

If I came to visit you, you could unplug your toaster and plug in my entire house.

(bell clinking) I could then run everything at the same time off that plug.

Energy efficiency wasn't our main goal with the TinyLab- we set out to make the world's highest performance tiny house on wheels.

But by controlling performance, we get energy efficiency as a fantastic byproduct.

Seems like you can have it both ways.

While we may be the first to tell this story on TV, before today you probably had heard of energy efficiency, 'going green,' maybe even noticed certain building certifications.

But now we hope you understand why those goals only tell part of the story.

- On the next episode, we'll dig into the spookiest part of every home in my opinion: water.

How it can get in your home, why you really wanna control it and also how mold is only the tip of the iceberg.

To learn more about any of these topics and the science you learned today, go to HomeDiagnosis.tv- We'll see you next time.

(Harmonious music) - Home Diagnosis is made possible by support from the Alfred P. Sloan foundation.

by Fantech, 'Breathe easy', by Broan-NuTone, 'Come home to fresh air', by AprilAire, 'Everyone deserves healthy air', by AirCycler, Retrotec, Santa Fe Dehumidifiers, by generous support from these underwriters, and by viewers like you.