- [Narrator] Coming up on Home Diagnosis... - [Corbett] Let's explore for a minute, what it's like to be a window.

- [Grace] we just felt a little lost.

- We brought you to where the windows are made.

Windows are important.

But they're only a part of the whole system.

I cost my family another $450 a year using the worst window available.

- We've got the blower door set up, and we are ready to test.

Are you feeling a little nervous, Mr. Lunsford?

- I am a little bit nervous.

- [Bill] There's so many facets about why it's better to build a house in a factory.

- [Narrator] 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.

- So far in season two, we've explored home planning, design and foundation work and dug into the realities of construction and renovations.

So now is a great time to dive into how we got here.

Why did this system of the home evolve into what we see today?

- So: the original shelter.

A tree in a field.

You wake up on the ground, having been cold all night, and now you're wet with dew.

We can do better.

- You build a fire.

Now you can cook and you're warm, but only on the half of your body that's facing the flames.

We can do better.

- Probably by accident, you discover that you can warm both sides of your body when you sleep by building a short reflecting wall that bounces the heat back at you from behind.

Now we're getting somewhere.

- Let's build taller walls and put a roof on it.

Awesome.

Now we have a real shelter for our family to protect us from the wind and weather.

But there's a problem.

It's so dark in here.

We can do better.

- Great idea: punch a door and some windows in our walls, and now life is better than ever.

We have fresh air, light, we can see when the neighbors are about to knock and hide if we need to.

No one wants a home without doors and windows, but like anything else, they have upsides and downsides.

And in order to get better control of your own home's performance, you need to understand how they influence the invisible dynamics around you.

- So let's shed some light on it.

- [Grace] They say 'home is where the heart is.'

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

So how hard could it be to build another one?

- [Grace] I'm Grace.

- [Corbett] And I'm Corbett.

- [Grace] 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.

- [Corbett] 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.

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

- [Corbett] While this is a personal story full of twists and turns... - [Grace] It's also the story of the science of homes.

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

One of the things that we asked Jodi to do for us, when she did her architectural finessing here, is to place the windows.

This TinyLab, has windows that fit inside of the 24 inch on center, spacing of the studs.

So we just kind of put them wherever we wanted to, for the most part.

- And when you're designing 200 square feet, you only have four walls to think about windows.

But here we had several walls and two stories to deal with, and we just felt a little lost.

- And so she helped us to place the windows, knew how many windows would feel good from the inside.

This whole thinking about a space without it being an existence, thinking in 3D modeling, is a very strange skill to have.

And we have it for some things when we're talking about performance, we can kind of do that with a house in our heads.

But as far as imagining a space that doesn't exist yet, that's one thing that I think an architect can really do that we don't have the ability.

So where to place windows is a very important conversation, and we're going to get into this when we talk about the sun and the effect of the sun on your house later.

But this over here is the energy model.

It's just a bunch of numbers.

But the numbers are very important.

So what we have here is the house built inside of the computer environment, with these numbers, all we've done is build all of the walls and then we're going to simulate the heat flow through these walls, which is a very simple mathematical calculation.

You can actually build an energy model on a piece of paper, if you really wanted to.

I do not want to, so I use this software for it.

But essentially I've got the size of the building, the amount of air inside of it, and I have importantly here, the windows and doors that appear to be windows- that's any door that has a bunch of glass in it.

And we've decided on a triple-pane window with argon gas inside.

So if I hit this button, all of a sudden I have populated all of the annual energy costs, the annual consumption of heating and electricity that I'm going to use.

And I can see that my total costs is about $1,500 a year on utilities, if we use these triple-pane windows.

If I was to replace all of these with a quadruple-pane window, that is twice as insulated, now it's $1,541.

So I just saved my family $22 a year by buying windows that are twice as insulated and have twice the Solar Heat Gain Coefficient.

If I was to step back and see what happens if I put in a worse window, let's just, for the sake of argument, put in the worst window, which is a single-pane metal window.

So now we rerun this, and my $1,500 a year, turns into $1983.

I cost my family another $450 a year in utility bills by using the worst window available.

This modeling process is how you determine what you're going to spend money on, and how you prioritize what to take seriously in performance.

Let's be honest: windows are a big, big business.

Lots of money is spent in marketing to make you think your home's performance problems can be solved with new windows.

- And while we're being honest, let's also admit that truly bad windows are a major drag.

If they're wet or icy, or if you can't see through them or open them anymore, then yes, upgrading your windows might be a good idea.

- [Corbett] But let's explore for a minute, what it's like to be a window.

People expect a window to protect them from the elements, like a wall.

They usually expect it to open easily and close tightly like a door.

And they expect it to be completely transparent, as if it's not even there.

- You might have the kind of window that's sweaty, and maybe that's because it's an aluminum single-paned window from the 1960s.

But it's also possible that it's not the window's fault at all.

If the home is airtight enough that it needs outdoor ventilation, then the air inside might be too humid, in which case a new window will sweat just like an old one.

- You'll hear commercials say 'new windows will be twice as insulated as the ones you have.'

A double-pane window is, in fact, 100% more insulating than a single-pane one.

But even if you drop good money on a very nice R-5 window- five times as insulated as a single pane- it's still just a drop in the bucket.

Because your home is a system.

Your expensive new R-5 window has the same insulation value as: an uninsulated wall.

- And we've seen plenty of 50- to 100-year-old single-pane window frames actually perform just fine.

So don't assume age equates with bad performance.

Lots of brand new windows get installed badly, and then the frame warps until they're not water- or air-tight, and the seal breaks and you can't see through them.

- [Corbett] Windows ARE important.

But they're only a part of the whole system.

So before you let your friends and neighbors spend tens of thousands of dollars, replacing their windows, have the home performance tested first to make sure it's worth it.

- So you can see behind us, we got the blower door set up and we are ready to test.

Are you feeling a little nervous Mr. Lunsford?

- I'm a little bit nervous because as a beginner builder, I don't know what my crew is capable of.

So, me and my mom and my dad have been sealing this up, and Grace and I installed the windows together, so we're pretty sure that we did a good job.

But of course, being pretty sure is what everybody does.

We want to know for a fact.

This is called a rough-in test, so we set up the blower door during construction, where we can locate some of the problems that we've built into this thing.

- So now we're going to go find any of the problems and we're going to fix them.

- I don't know what we're going to find out in just a second here.

I like to think that I'm a good builder, but this is the first step that anybody has to deal with, when you start testing.

The very first thing that you come up against is: 'do I do a bad job?'

Which is why most contractors will never test.

And that's just the way it is because a lot of people are very afraid of what they would find out.

We have the 3D model, that we've been working with all along and from that, I have pulled some stats, which is really cool.

This is what your blower door report should look like.

It's very complicated because there is a lot of information going on here.

We see the weather today, the wind levels, all that stuff has a big deal toward this.

We have 3,015 square feet of conditioned floor area.

We have 47,889 cubic feet of air that is contained by our enclosure.

The enclosure itself is 9,611 square feet of walls, ceilings, and floors.

All that stuff is to say, I know exactly what we're shooting for.

So before I run this test, I know what configuration I want to set my fan up in because I know what number I'm looking for.

3 Air Changes per Hour or less when we run this test will future-proof this house forever.

And in fact, it's gonna get more air tight when we keep doing more sealing to it as we keep building.

But if I can hit under 1 ACH50, which is three times better than what code will ever require, that would make me really happy right now.

That number is somewhere between 800 and 1200.

So we have almost no wind happening outside.

All right.

Here, we, go.

(blower door fanning) Amazing.

(cheering) Alright so, if you can see here, what just happened was the numbers went down, down, down- is because it was estimating at the beginning.

Now that we're at 50, we're at less than 400.

In fact, it keeps disappearing because it's so low and the fan is running at such a low speed that we can't even get a number to them, so I'm going to actually have to seal this back up.

(blower door fanning increasing) That's great news.

All right, so while it's building, you can hear the fan is ramping up, trying to get really dialed into 50 here.

We're looking at 300 and something like 330 CFM 50, which is actually better than the most stringent building certification in the world.

And we're not even done air sealing yet, which is what the great news is.

We will poke more holes in the walls and stuff, but this, that makes me so happy.

This is twice as good as what I was hoping for in my reasonable dreams.

So, OK, we finally dialed in: 311.

Woo!

That's what we're talking about.

So again: hi, my name is Corbett.

Sometimes I'm an idiot.

And if I can do this on the first big house that we've ever built, any builder can do this.

If they have a crew who knows what they're doing, they would do it faster and less expensively than I have done it here.

So please take that.

Take this message to your contractors and builders because this is not rocket science.

And we just proved it.

Woo!

Now to see how much of an impact the performance of these windows can make, we brought you to where the windows are made.

We're at a high-performance window factory, because, of course, this is the show for that.

But aside from the special stuff that you're going to see, this will apply to windows of all kinds.

- As you've heard us say on the show many times the home is a system.

These windows are a system, a very cool system.

So we're gonna go back into the factory and see how they're made.

- So as we walked through the factory, we're going to see a few of the key stations that make the window as high-performance as it is.

We'll start in the cut room where all of the lineals of material come into the factory.

So we are either painting them or we're sorting them by color.

Because the fiberglass can be painted, UPVC cannot.

You'll see the difference between the two products is it's quite striking- as you manufacture the fiberglass windows, there's a lot of pieces and parts that hold the whole system together as it's going through the machine.

These very fine pieces of glass, they're sort of like horsehair.

They get pulled through and formed with resins and heated up to be thermally set.

Whereas in the vinyl window, because it's not a thermoset material, it's still soft.

We just have one machine that clamps down all four corners and heat-welds it together.

So there's a lot fewer steps in in the UPVC product.

So this is the UPVC frame.

You can see there's multiple engineered chambers inside of it.

We have insulation and air cavities.

And then we also have ladders that hold the screws to provide structural strength.

So here at our factory, we don't actually melt the sand and float the glass.

There is a factory nearby that provides the stock sheets of glass to us, then we assemble our glass units.

These are the gas expansion chambers.

So we ship them to go higher elevation or lower elevation.

We put a balloon on it, so that it's like, it's going like up in elevation, the gas wants to escape.

And as we go down in elevation, it wants to suck the gas in.

So we'll over-fill the balloon when it's going down, and we'll leave it flat when it's going up.

- But you can't take one that was going to Aspen and sell it to Florida and stuff?

- Not without that tube still on it.

- So one of the important things about the system of this window, is that it's filled gas.

There's a couple of different gases that are used: argon, xenon and krypton.

They're heavier than air, which make it a higher performance window.

Here you've got the gas coming in through these little ports and up here, you've got two sniffers and that helps them know when the window is full of gas and they can stop it, put in one of those balloons, seal up the window, and be ready to go.

- We have few basic constructions of glass, one being true triple pane, where you've got three layers of glass substrate.

Most of the insulation is coming from that gas fill, and from the Low-E coatings that stop heat from going through the window.

- So the Low-E coating- that keeps the heat bleed from radiating through the window.

As I understand it, it's directional, right?

So I can have one coating of Low-E if I wanna stop heat from bleeding out of my house, but then I needed another one if I wanna stop heat from bleeding in with the sun.

How does that work with the window manufacturing process?

- So the most important thing is, within a multi chamber IG is to have one Low-E facing each chamber, so they're essentially insulating those chambers.

So usually you want a solar-selective Low-E coating on the outside layer- that's going to do the filtering of your solar heat gain.

And then you'll put your Low-E coatings on the inside.

What we feature most is a suspended coated film unit.

So we're taking two pieces of glass and sandwiching them around a piece of Mylar film, and you'll see that the Mylar film is still a bit wrinkly.

The key to pulling those wrinkles out is stretching the film in the ovens- with a big blue oven that we heat up to 220 degrees.

We cook it for about an hour and it stretches out and you can't see the film anymore.

We love this product because it is super lightweight, and there's lower embodied energy in the unit than with true triple pane glass.

So on casement and awning windows, when you're cranking them out, if we can reduce the amount of weight on that hardware, that might sag if it's left open for too long, then we can prolong the life of the hardware.

The third benefit to film, the part that I love most, is that the film does carry a Low-E coating on it.

So usually in triple pane construction, you don't coat the center pane, it's just very hard to get through the glass wash and get super clean before you're making the unit.

So when we have the film as the center pane, we can actually get better performance than a triple pane window.

But also, if you have a skylight, or you're going into an impact hurricane zone, you have to have laminated glass.

If I had a triple pane window and I put on laminate, I lose my Low-E, because that's where the Low-Es' are- on the inside and outside.

The suspended film, because my Low-E is on the middle, I can do anything I want with that inner pane- I can go impact- or blast-resistance or terrorism force protection, really the full range of options.

There's over 216,000 combinations of Low-E, gas, glass, film, and spacer that we can make, and it's really fun to model them.

We like to have our customers say, 'I need a U-value that's this, and a visible light that's this, and can you get there?'

And usually we can, And that's all due to the film, being the carrier of the Low-E. - [Grace] Windows aren't the only high-performance product being built in factories.

Let's take a look at what it's like to put together an entire house on an assembly line.

- The actual construction of the house happened over four weeks.

The modular foundation is precast concrete that you can then set the house on top of.

So the foundation was put in, in a day.

Maybe four days later, the house was brought to the site.

They brought the modules together on site and they used a 120-ton crane.

The modules themselves are about 40 tons each.

This factory has been in existence, the one that we used in Northwestern, Pennsylvania, for 30 years.

Not a lot of builders are building high performance homes in the factory right now, but this factory perhaps learned some things from our experience- things they'll do again and some things they won't do again.

There's so many facets about why it's better to build a house in a factory.

One of the things is materials of construction.

The materials of construction are all under a roof.

They're delivered from the factory where they come, to the assembly line, and things are built.

And things are also built from the inside out, which is very different than typical field or stick-built construction.

You also have workers who are consistently the same workers, doing similar jobs, day after day.

The scaffolding that's constructed around the assembly line- people can reach what they're working on from a comfortable position.

They're not up on a ladder.

They're not worrying about their safety.

They're not worrying about the outdoor elements.

They can be working more comfortably.

That includes above and below.

The house module actually moves over a pit, like you might see in some old-time garages where people are doing an oil change from underneath.

But the pit underneath, they'll be doing the wiring, the plumbing, all the underside work can be done from a comfortable position.

So you have people focusing on the work, and not just trying to get the job done, but get the job done correctly.

- Of all the holes we purposely make in our homes, there's one that's much more complicated than it seems: a skylight.

- Well, skylights seem like a terrific idea.

Bring in light from the brightest place possible: the sky.

Ventilate your home, with a window that acts like a chimney.

And maybe watch the stars while you're falling asleep in bed.

- But the roof is the first line of defense against rain, snow, and hail, and you just put a hole in it.

If you want to prove it won't leak, better run a water tightness test before you call it a day.

- Plus, the ceiling is also where you get the most natural air pressure from stack effect, and you just put a hole in it.

You don't want to cause condensation and comfort problems, so you better run a blower door test to prove that the connection is airtight.

- The roof also shields you from the sun, so a skylight cut into the ceiling may dramatically change the temperature of a room.

The ceiling of any home, actually gets insulated to a higher level than the walls.

You'll love the reason why: outer space.

- While the warmth in your home gets sucked out on all sides by things that are cold and outer space sucks harder on your house at night, than the neighboring houses, landscape, or weather ever does.

- If you just can't resist cutting a hole in your ceiling insulation to put a skylight over your bed, get the most insulated one you possibly can and the most skilled installer to do the job.

Money can buy happiness sometimes.

- And always remember: the home is a system.

You get diagnosed by a doctor before getting surgery on your body.

Do the same for your home.

Stop guessing.

Proof is possible.

- To get light into the interior rooms of our home, where we couldn't get windows.

We opted, instead of skylights, to go with sun tubes.

Not only are we able to have the positive performance aspects of the water tightness, the air tightness, the insulation levels that we want, but also we get a very good quality of light in these interior spaces.

We have one in this top floor bathroom, and then we have one that goes all the way down to the first floor master bathroom.

And of course all the seams are taped, just like normal ductwork.

It's very lightweight because interestingly, I had thought, 'oh, this should be really strong.'

But all it's carrying is light, which weighs nothing, and it's not really going to do anything to these ducts.

These seem like they're just regular ductwork.

This is an example of just a regular duct.

It's galvanized metal, sheet metal.

That's not what this is made of.

This is a mirrored interior finish.

And it grabs a lot of light because it's a high quality collector.

Once we settled on the exact insulation value that we were looking for with the windows, there's a bunch of other factors to consider.

You can have windows that don't move like these.

They're called 'fixed'.

That is beneficial for performance because they don't have a lot of air leakage and water leakage issues that other windows that do move, like this one, would.

This one is called a 'casement,' so it opens up like a door.

This window is a typical American install, which is known as a nail fin install, so it's basically got this fin all the way around.

You slide the window in from the outside and the fin meets up with the building and then you attach it.

As you can see, we've got screws here through this buck.

We're going to tape and seal everything around the window, on both the inside and the outside, with the exception of here at the bottom.

On the bottom of the outside, we leave this unsealed in any window install because just in case water gets in, it can come back out where it belongs to the outside.

We do, of course, since we're in Atlanta, want to limit the amount of sun's rays that are coming in and heating up this space.

But we also opted for the radiant barrier that is the Low-E coating that's going to prohibit heat from bleeding out through this window at night.

We know from the energy model that this is going to be good enough to give us the performance that we're looking for.

Remember, you're always trying to tune not just the enclosure to itself, which we're going to get into in the next episode, but we're trying to tune the enclosure, to the heating and cooling and drying and ventilation machines that we're going to install- the engines, which we're going to get into in later episodes.

Don't let anybody just rush you into, 'oh, here's what you want.

Everybody buys this one.

It's what's good.'

It's the same as going into a restaurant and saying, 'what's good here?'

And they say, 'Well, this is the most popular.'

That's not what you want.

If you're watching this show, you want special stuff that most other people are not after.

So look into the options.

Again, we're looking at insulation value.

We're looking at what the Sun can do coming in, what heat will be able to leave going through.

What the functionality of the window is, which way it opens, if it opens at all.

And all of that goes into your decision making for these windows.

And remember, that a giant glass door is a window that's just humongous, so you want to make the same exact decisions in that case.

- Can we talk about money?

Often I look at our spend at the end of the month and I think, 'Whoa!

Where did it all go?'

But when it comes to your family, you might happily spend a little more on the organic juice or all natural pet food, or sacrifice your gym membership so that your kids can take ballet or soccer for a season.

Because you want the best for them.

And when you're building or improving your home, you should keep that 'best' principle in mind.

Your home has a massive impact on your family's health, comfort, and let's face it- your sanity.

For example, replacement windows and doors are classic pitfalls for people who love discounts and inexpensive options.

If you skimp on your home, you are skimping on your future.

Our work on Home Diagnosis aims to give you the skills to judge what best looks like.

But you say, 'Grace, I am still confused by the marketing I'm seeing, and the builders I've sought out for better performance won't return my calls.

And you know what?

My cousin said, he could do it for free sometime next weekend.'

I get your frustration.

Nothing worth having comes easy.

So here's a little home performance, tough love reminder: You get what you pay for.

You know what you're getting with anything advertised as 'pro quality, DIY prices.'

The more education we can offer people like you through Home Diagnosis and our website, the more questions builders and contractors will get about proven performance through testing.

And this is what changes the equation, because the boss of the entire home building and home improvement industry is... Ta-daa: you.

You can find professionals who can give you the best.

And in 20 years they'll be knocking on your door.

But right now, it does take a little more legwork to find them, but you can do it.

Proof is possible- ask for it.

Now that we've started our odyssey with the holes we make in our homes, hopefully you feel more confident making decisions in your current and future homes.

- Next time, we'll be investigating the many layers that these windows and doors interrupt, and how you can tune them to make your home as healthy and comfortable as you want it to be.

- Until then.

(upbeat music) - [Narrator] 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.