Insulating the Roof and Installing Mold-Resistant Drywall

Project: Building an Addition for an Elderly Parent, Episode 5, Part 2

The addition is nearly complete and it is time for the mechanicals, porch, flooring, and fireplaces. Homeowner Howard Brickman is putting a large farmer’s porch along the entire width of the home. He uses western red cedar for the decking and trim because of its natural tone, strength, and rot and insect resistance. A green building material, western red cedar boards are a dream to work with because they can be applied as decking or ceiling, vertical or horizontal siding, and with the rough or smooth side facing out.


Inside, Bob checks out the hydro-air boiler that runs the heat, hot water, radiant floor heat, and the indirect hot-water tank with a dual-coil feed to make use of the 30 solar heat collectors on the roof. Bob checks out the radiant-floor heating tubes, copper supply and return pipes, and the solderless sealed joints. The roof is insulated with dense-pack blown-in cellulose that is borate-treated for fire retardancy, mold and insect-resistance. Fiberglass-faced sheetrock completes the installation for mold-free walls. A new wood-burning fireplace is installed and faced with a lightweight thin-stone veneer. Prefinished red oak flooring is installed, the walls are professionally painted, and birch-veneer four-panel doors are hung.

Part 1: Constructing the Porch and Reviewing the Mechanical Systems
Part 2: Insulating the Roof and Installing Mold-Resistant Drywall
The roof of the new addition is being insulated to retain all the heat generated from the radiant heating system. Paul Johnson of Alpine Insulators reviews the installation process. Fire-retardant netting is stapled in place to hold dense-packed cellulose in place. Cellulose is a great thermal insulator and sound attenuator. In the interior partition wall where the bathroom will be located, cellulose will be installed directly against the drywall.

Bill Hulstrunk of National Fiber discusses cellulose insulation, which has been around since about 1920 and used extensively since 1970 in both new and existing construction. Borates are added to make the cellulose fire retardant, and mold and insect resistant. Because of the added borates, a propane torch can be put to the cellulose without igniting it. These borates are naturally occurring and the cellulose is made of 83 percent recycled content, making this type of insulation an environmentally conscious, green choice. The cellulose in this house is being used in an unvented application. Because the material is packed very tightly, it reduces the chance that warm, moist air will penetrate the cavity and create mold growth.

Georgia Pacific DensArmor drywall is being used throughout the addition. The face of this drywall is made of fiberglass so there is no danger of hosting any sort of mold growth. Attaching the drywall to a foam-and-concrete structure posed a bit of a challenge. To address this, steel J-beads were installed horizontally as nailers for the drywall screws.
Part 3: Putting in a New Fireplace, Painting the Interior, and Installing Doors and Floors
More and more homeowners are converting their houses into multi-generational homes for themselves, their children, and their aging parents. In Norwell, MA, Bob Vila meets a couple making room for a mother-in-law.

Also from Building an Addition for an Elderly Parent

  • Episode 1 - Reviewing Wetland Protection and Laying the Foundation


    <p>Bob introduces homeowner Howard Brickman, who is building a new addition for an aging parent that will nearly double the size of his colonial home in Norwell, MA. It showcases concrete building technology that is streamlined, efficient, and versatile.</p> <p>&nbsp;</p> <p>There were some delays in obtaining a building permit because the home is near a quaking bog that serves as a wildlife habitat and natural filtration system for the town. Steve Ivas, an environment consultant, leads a tour of neighboring Black Pond Bog.&nbsp; Formed by melting glacial remains, the pond is covered by a moss layer that has since formed a 20-foot thick fibrous mat.&nbsp; At the home site, a hay-bale buffer was created on the property to protect a connected wetland from erosion or runoff during the project.</p> <p>&nbsp;</p> <p>At every step, time and materials savings speed the construction and save countless hours of labor.&nbsp; A monolithic pour, or single pour that would normally take three, is used for the concrete slab and frost walls.&nbsp; ReddiForm's innovative plastic footing ICF forms are used to create and reinforce the structure.&nbsp; Insul-Tarp is used to create an insulated vapor barrier and reflect heat back into the living spaces.&nbsp; Fibers are blended into the concrete mix, eliminating the need for a traditional steel reinforced mesh.</p>
  • Episode 2 - Building the Foundation, Floor, and Walls


    <p>The finished addition will look like the original traditional shingled home and be indistinguishable from the house, but the construction technologies and innovative products in use are anything but traditional. Bob talks with Ron Ardres from ReddiForm about their polystyrene blocks, or ICFs, that reduce steps and labor.&nbsp; With contractor Todd LaBarge, Bob learns about Insul-Tarp and efficient concrete pours.&nbsp; Jason McKinnon of Viega North America and Tim Cutler, of TJ&rsquo;s Plumbing &amp; Heating explain PEX tubing and radiant heat.&nbsp; Jim Niehoff of the Portland Cement Association and builder Howard Brickman talk about the almost unheard of speed with which the addition is coming together and the anticipated energy-efficiency of the new building. By using concrete and foam construction for the footing, garage, first-floor slab, and walls, and also being used to set up for the upper levels of the addition, significant savings in time, energy, and cost are achieved.</p>
  • Episode 3 - Installing Garage Doors, Framing the Interior, and Upper-Floor Decking


    <p>Bob is on site where insulated, steel garage doors are being installed to replace the original, low-budget fiberboard doors. He walks through the new insulated concrete addition with the homeowner Howard Brickman, who explains how the layout of this in-law addition essentially doubles the size of the existing home. They talk about the concrete construction, how quickly it went up, and how insulated concrete form (ICF) construction allowed them to get a basement and slab, full upper story, walls, and first floor poured for nearly the same amount of concrete as a traditional basement wall-and-slab design.</p> <p>&nbsp;</p> <p>This building process purposely uses innovative techniques and improved building practices &ndash; like the stay-in-place forms for the footings, the under-slab insulation and vapor barrier, the engineered lumber for I-joists and rafters, and the innovative DryPly decking being used for the second floor. Not only do these these technologies reduced waste, but any waste generated is being sorted for reuse.</p>
  • Episode 4 - Metal Roofing, Solar Roof Panels, Siding, and Trim

Hi I'm Bob Vila. Welcome to the show.

Our edition is for long and today, we're putting up some beautiful cedar siding on the front under the porch.

Also, inside we're installing a brand new state of the art boiler, that's going to do a lot of different tasks.

We're insulating using cellulous blown in insulation.

Inside we're putting in a fireplace and working on the drywall and putting in wood port doors.

Stick around, it is good to have you with us.
Now, the front of the house is gonna have a big farmer's porch with a roof over. all the way cross the whole width to the house, perfect rocking cheers, and we are using western red cedar to trim everything out. Now this is western red cedar 2 by six, which we will use for decking. And Howard is back there starting to put some of the siding in place but Peter Lang is with us from the Western Ridge Cedar Lumber Association.

Sorry. How are you Peter?

Hello Bob.

Sorry to bring such a cold windy day, but let's talk a little bit about the reasons why western red cedar is such a good choice for exterior applications.

Well there's several reasons. First of all in applications such as siding, it is very exciting, it's a very visible part of the house, so therefore the look is very important and western red cedar is renowned for it's natural beauties. So it will certainly greatly enhance the look of the house, the curb appeal.

Yeah, in this case we're using tongued and grooved with a v in each one right?

Yes. The product is a 1x6 tongue and groove. Tongue and groove. It is a potentially a reversable. One of the more /versatile cedar patterns in that it is a potentially reversible product.

You could put rough sawed part out?

You could put rough sawed part out or the smooth faced, depending on the look that you want to achieve it.

And of course you could use it horizontally or

Or vertically. That's correct and of course even in the ceiling applications.

In the ceiling applications

In the ceiling applications at times.

Yeah and Peter is western red cedar consider a green material?

Cedar is very definitely a green building material. It is for several reasons. First of all, it's one of the few building materials that are naturally renewable, comes from a renewable resource. Also it is harvested in a sustainable manner from well managed forests, many of the forests, many of the companies To our engaged in the business our harvesting from Certified forest third party certification systems such as SFC and CSA to ensure the highest standards of forestry are being practiced.

In addition, cedar there of course is recyclable material. It's biodegradable.

Sure. But I was telling you from a carpenters perspective its a dream to work with.

It absolutely is.

Thanks Peter. Thank you, thank you

Ok. Tim Cutler is with us now from T.J.'s Plumbing and we're listening to the the Weizmann we've got three different kind of things happening here, right?


can you take us through it I can we have a boiler which is heating our domestic hot water. Its also heating our radiant heating system and its running up hydro wave of heating point here All right. The hydro air system is a air handler with a hot water coil inside it.


So the water gets heated by the boiler, sent through the coil, and then sends warm air out through the building.

Yeah, and that primarily is for the existing older part of the house, right?




And then what about domestic hot water needs, for the showers and the kitchen, etc?

The showers and the kitchen get fed by a 79-gallon indirect domestic hot water dual-coil tank, okay? The bottom coil gets fed by our solar system, which has Viessmann evacuated tubes, okay?

How many of them?

There are thirty on the roof.

This is a copper fin, you can actually see it right here.

There you go.

What happens is it has alcohol inside this, it has a very low boiling point.


When we boil, it transfers the BTUs to this bulb, and we pick it up and send it through this lower coil, which heats our domestic hot water.

OK, and then on the other side of the room we're going to talk to your colleague about the PEX part of it, right?


All right. Thanks Tim. Then going from the old part of the basement to the new addition what we did was we had a concrete cutter come in to provide this opening.

And over here Bill Sloan is here from Viega. Now the heating in the new addition is actually up in the slab, right?

Yes, these pipes run up in these fire retardant pipes from the slab.

And these are all PEX?

These are all PEX tubing.

Right, and then Viega is manufacturing the manifold?

Yes, yes. And this copper system here also which is ProPress system, which is both the supply and return pipes. You can feel the hot water going up and then, you can feel the return pipes...

Returning cooled off.

...cooled off.

Right exactly. Oh yes, you totally can Now what kind of joints are all of these?

These are pro press joints, Bob.

Pro press.

Pro press. It's a copper system, that's been over in Europe for over 25 years.

And it doesn't require any soldering ?

No solder, no flux, no torch.

Have you got a sample?

Yes I do. This is a pro press fitting. Basically you can press from half to four inch kale or in copper. Soft copper from 1/2 inch and a 1/4.

And then there is like a black something in there right?

That is an EPDM saline element commonly referred to as an O ring.

An O ring?

Yeah. Ok.

Excellent. So this is all done right?

Yes it is.

I wonder why it's so cold in here? Thanks a lot.

Thank you. And inside the house, we've been busy insulating that new roof to keep all the heat in. Howard chose to use a natural product as well.

Well the first step is installing some netting. This is a cross- linked polypropylene netting.

The most important feature of this is that it's breathable, so that when we blow in at high pressure the cellulose, the air can come out and escape so it can be packed very densely.

Ok this, this is a fire retardant netting. It's stapled up in a very tight manner so that we can get a maximum amount of cellulose in here.

In the truck we have the insulation sheet. There we empty the bales of cellulose where they are shredded up even further, and they are pumped at a high pressure through these hoses and into the cavities.

Here where we have a roof assembly with 2 by 12 rafters, where we had scrapping and we've netted over it, it would cost about $2.25 a square foot. Cellulose is not just a great thermal insulator, it's a great sound attenuator.

In this interior partition wall of the bathroom, we will be installing cellulose, directly against the drywall, prevent sounds from traveling from the bathroom to the hallway.

Cellulose insulation has been around since 1920, and has been used extensively since 1970, both in new and existing construction.

It's the borates that are added to the material that really give it the, the enhanced fire-retardant, mold inhibitors and repellent for insects .

The key thing to know about Newell is that this isn't just ground up newspaper . This has borates added that impart significant fire protection to the material. In the field we can do a test where we take a a propane torch, and put a penny on here, and can melt the penny without the heat actually going through and you know, heating up your hand or affecting your hand.

After that cools you then scrape away, you know, an eighth to a quarter inch of material, and there's fresh material underneath that.

Not only do Borates offer significant fire resistance but they are also mold inhibitors and resist insects but the best thing about boards are naturally occurring, and that along with a material that's made from 83% recycled content really offers environmentally green, green product.

In this house, we're using the cellulose in the unvented application. So first of all we're going to maximize the potential or the depth of thickness of the insulation, by fully filling that cavity.

And then because we're dense packing or packing it in very tightly, we will eliminate the potential for warm moist air to permeate through that cavity and potentially condense, and that offers the both the performance of the insulation and the protective aspects of the material. Now, we're using Georgia Pacific DensArmor drywall throughout the house.

And you know, one of the great advantages of this kind of innovation in dry wall is that, because the mat basing is not made out of an organic paper, it's made out of a fiberglass type of paste, you don't have any danger of hosting any sort of mold growth.

And that's a really important thing nowadays in most house construction.

Here we also have the added complexity, if you will, of having to install it onto this concrete and foam structure.

So there were these steel J-beads that were inserted horizontally, and they provide nailer, if you will, a place for the drywall screws to fasten to, and that's how they all were installed. and so the walls are just about ready for paint. And over here, we've got a feature that I think will really make the living room of our in-law suite very, very cozy.

Basically what this is, is a majestic wood burning fireplace. And what's unique about it, compared to most fireplaces, is this actually uses outside air for combustion. It draws the air in from the outside to feed the fire.

It operates similar to a wood stove in that, when you have the fire operating in it, you're going to run it with the doors closed.

What we did is we measured ahead of time to make sure that we had enough room for them to put the finish material on, the marble and the mantle and all that type of thing. So we measured out from the two sides and allowed for a six foot mantle, basically.

What we are going to do now is, we're going to get the pipe.

There's a wall upstairs that's lined up with this wall, and it's also lined up with the peak of the roof, so we want to make sure we stay far enough enough away that we can get the flashing to fit on the chimney without getting on the edge of the roof.

So we're going to use a couple of these components here.

These are 30 degree offsets and these are the the most you can offset these chimney systems.

You can use multiple number of offsets. I think you can use up to four on this particular fireplace.

All of this information is always sent with these units. They have very thorough, very intricate manuals that come with them, that explain all this stuff.

And that structure for the fireplace is now being trimmed out with real stone, right? And John Nadler is here from Plymouth Quarries.

That is correct. How are you Bob?

Now let me ask you, I mean we've used man-made stone products in kind of veneer or Ashlar installations before, but this is real stone.

This is actually real stone. Taking the principle of the cultures own as you're familiar with. They actually saw cut thin, they actually took real fit stone and saw cut it thin so it can be applied as you would a typical caulk and stone or a man made fabricated stone.

Is it native field stone in Massachusetts or what?

It's actually a New England field stone, it's from Connecticut. This particular stone, but there are also stones from New York, and out west.

Ok. And, how easy is it to cut it? I mean isn't it...

You can cut it with a hammer. You can cut it with a four inch grinder, you can cut it with a wet saw. Its that easy to cut this thin stuff.

Okay, and the cost?

The cost typically between $12 and $15 a square foot, in some cases be a little bit less. In some cases, it'll be a little bit more. Depending on the type of stone, of course.

Yeah now normally when we think about field stone fireplaces you're thinking about big stones that are stacked all on top of one another...

That's correct.

... and there are tons of masonry there you have to support with a big concrete slab.

And you're 100% correct when you're saying tons of stone.

Yeah. in this particular case, its a lightweight stone product. its not the stone that's light weight, typically less than fifteen pounds to the square foot, as opposed to the natural stone or the four inch stone which is fifty pounds to the square foot.


This actually works from the top down. You can actually hang this from the top down.

It doesn't require any structural footings underneath, so you have a cost savings there, too.

That's a big advantage.

Now we're going to interrupt Joe McDonough and Joe, I understand you built the original chimney when Howard built this house twenty-five years ago.


Is that right?


Well this is such counter intuitive work. As normally, as I was saying a minute ago, you feel like you start at the bottom and go up, but you start at the top, and it looks

work our way down.

It looks beautiful. Now how do you fill in the joints in between.

What we do is use a grout bag and we buy these at a pastry shop.

Yeah it looks like a cake decorating sleeve.


You just squirt.

The more that comes out

Can you show us?

just like that. And you just go along. That's a great tip.

Fills it right in. It's nice and neat.

And then do you have to like use a trowel or anything to finish it off?

No what we use is we actually use a stick.

Just a pointed stick?

That's all it is.

Out of the woods.

It's old time. And just scratch the joints out.

Yeah, as it dries out.

As it dries out, you let it set up, usually a couple of hours.

This has been setting for two or three hours now, Mike?


About two hours.

Yeah. And then you just go over it and brush it and take a brush, and brush everything out.


And that's it.


It's a beautiful job, congratulations. Thanks John.


Very nice. Alright So we're with Brian Miller, at Miller and Sons Painting right now.

Hi Brian. And that's Joe up there.

Cutting in, right?

Yes he is, Bob. Joe is cutting a straight line across where the two surfaces meet. He's forming a straight line, so we can bring that wall right down to the ground.

So if you've never painted a room, you ought to know that the first thing you do before you even get a roller out is to go around all of these corners and edges, and fill in.

How wide should you normally go?

You should try to bring it down two to three inches, so you do have enough space to bring the roller up to where the wet paint is.

And not onto the ceiling.


Yeah. What kind of paint are we using?

Today , we're using Sherwin-Williams Duration. It's an interior latex paint.


It's designed for one coat coverage. It's a self priming paint as well.

All right, you've got a professional looking roller here, right?

Yes. We like to use these eighteen inch rollers just to get a smooth finish, and decrease the lap marks.

Lap marks would sometimes occur with a nine inch roller so that's why we do use the eighteen.

And what about the thickness of it, the nap of it? nap is a half inch nap. It's designed to actually put more paint on the wall.

Yeah, that looks great, it looks like we'll get away with just one coat, right?

Bob, it looks that way, and that's exactly why we like use this application, this paint.

Very nice job. Well, you've got 3 more to go, thanks Brian. And Howard, not only are you the flooring genius, but you're a jack of all trades, you're putting up your own doors, right?

Yes, Bob. Necessity makes us do many things.

How are you coming with the floors upstairs?

We're doing great, we're putting the bellawood, the pre-finished red oak. Beautiful material, goes together nice, we're really having a good time.

That's a very good choice, yes. Spinning towards our view.


Old Sparky, we call it.

But anyway, Dean Stewart is with us right now to talk about our wonderful wood port doors, and what kind of a door is this?

This is a four panel contemporary door with what we call Mission sticking. It's also commonly referred as a Shaker-style door.

Oh, 'cause the Shakers made all of the beautiful Shaker furniture that had the flat panels like that, usually on a horizontal design.

That's correct.

Very simple design.

Yeah. Now what's the construction of the door?

The construction of the door, this is an engineered wood panel with a birch veneer over the top of it. What's nice about birch and why Howard chose this for the project is simply because he wasn't sure whether he was going to stain or paint this door.

And because birch is such a versatile he wood, it'll turn out beautiful no matter what he ends up doing with it.

Now when you say an engineered core, just what does that mean?

What that is, is that is a veneer over the top of a very high-density fiberboard material.


And it just makes the door a lot more stable, so that it doesn't warp or have some of the tendencies that a solid wood would have.

You have less danger of moisture being absorbed into the door or et cetera, we've all had doors warped. Well, it's a beauty thanks.

You bet. And Howard? Good luck.

Thanks, Bob.

We're running out of time. Until next time, I'm Bob Vila. Thanks for joining us.



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