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4 Answers

Casement windows?

I'm looking for highly efficient triple glazed windows with a high solar heat gain coefficient for use on the south side of a new construction home in Massachusetts (Climate Zone 5). I like Schuco windows, however, I am looking to compare with a window that performs similarly but doesn't open into the living space. Any suggestions?

Asked By user-6776655 | Feb 26 17
15 Answers

Installing LP Smartside over foam and 24 inch centers

We’re building a new home (SW Virginia) with 2x6 studs on 24 inch centers. We had hoped to use 1.5 to 2 inches of EPS rigid foam to the exterior of the sheathing, then 3/4 inch x 4 inch plywood furring strips, then LP Smartside lap siding. We knew we had to use the 76 series Smartside product for the 24 inch centers. Then I discovered that LP’s installation instructions specify 1.5 inch x 3.5 inch furring strips for foam greater than 1 inch in thickness, so I guess that would basically mean a 2 x 4 stud for every 2x6 stud in the wall.

Asked By William Costello | Feb 17 17
8 Answers

Roxul Comfortboard to create cathedral ceiling baffle?

Hi all -- thanks for taking the time to read this.

I'll be building a new home this spring in zone 6 (northern Vermont) that will have cathedral ceilings. I've read a lot about the best way to do this in my climate (thanks for all the info on this site, Martin) and I've settled on what seems like a safe bet: taped drywall and vapor retarder paint, dense pack cellulose (16" or so), homemade baffle, 2" airspace, plywood sheathing, underlayment, metal screw down roof.

Asked By Blake Cote | Feb 23 17
7 Answers

Zip System R-Sheathing

Quick question about Zip System R-Sheathing.

The concept of a REMOTE wall, where exterior insulation is used to ensure that the structural sheathing stays warm (and thus dry), makes perfect sense to me.

The Zip System R-Sheathing is a compelling product because it saves several steps by installing all the necessary wall components in one go.

HOWEVER, from the pictures on their website, it looks like the Zip System R-Sheathing has the WRB on the outside, followed by the sheathing, followed by the insulation. So, doesn't this mean that the sheathing is cold?

How does that work?

Asked By Matt Culik | Feb 16 17
10 Answers

Modified Perfect Wall, What happens?

When looking at Joseph Lstiburek's Perfect wall system; What happens when we change the order of some of the layers. I am looking at the Zip-R Sheathing produce which would place the Water and Air control layers outside the Thermal Control Layer. Are there any concerns with this. The only downside I can see is that we no longer get the opportunity to use multiple layers of Insulated Sheathing with staggered seams.
Would this change depending on the climate region?

Asked By Jeff Classen | Feb 22 17
3 Answers

Sub-slab drainage details

New construction, planning out the foundation and basement details … I’ve asked our builder to install drainage pipes under our basement slab (~1000 sq ft), and have them connect through the foundation to the footer drainage pipe. Builder says ok (even though he considers this overkill), but it’ll cost us dearly in extra gravel. Had originally planned for a 4 inch layer of gravel (topped by 2 inches of XPS, then poly.) Builder says to install the 4 inch drain pipe properly would require about 8 inches of gravel.

Asked By William Costello | Feb 22 17
2 Answers

Sealing under-layers of built-up exterior foam panel insulation

Hello again GBA'ers.

Making progress on the details of my 6" graphite EPS over Zip panel exterior wall assembly, and coming down to the final few questions, I think.

At this point I want to use ThermalStar GX EPS, and the assembly will three layers of 2" to get to the final design depth, the outermost face of the outermost layer will be faced, but none of the others will be, which leaves two (I think) questions:

Asked By Gerald Pehl | Feb 19 17
4 Answers

Not enough XPS over roof - should I vent?

I am in the Washington DC area - Zone 4. I just had a 1.5/12 single slope roof framed with 2x8's for a 14x20 new block wall garage. On top of the rafters there is a layer of plywood followed by 2" XPS rigid foam followed by another layer of plywood and then an ice and water shield across the entire roof. This week there will be a standing seam metal roof installed on top.

Asked By Calvin Bouchard | Feb 12 17
2 Answers

Rainscreen with gapped panels

Hello Again GBA'ers

We have a design for a ventilated rain screen ventilated with mixed cladding materials. This will be exterior to 6" of foam board insulation. One of the materials is Equitone, and the manufacturer recommendation calls for 3/8" gap between panels, they supply a butyl tape to face the furring strips, both to provide a dark color on the reveal and to provide a moisture barrier on the face of the wood furring strip. The panels are very long, and there will be long horizontal gaps.

Two questions:

Asked By Gerald Pehl | Feb 16 17
20 Answers

Best cold climate exterior insulation assembly

Hello GBAers,

Long time reader, first time poster here. I have huge gratitude for this resource, and I've finally become a member.

We started on a PassiveHouse retro-fit journey quite a while ago, and we really need to finish- I'm gearing up to do that now.

Our architect spec'd 6" of polyiso on the exterior, fastened with 1x4 battens to which siding will be fastened, and which will also serve as a ventilated rain screen.

Asked By Gerald Pehl | Feb 9 17
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