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2 Answers

Double walls, dense packing, and bendy sheathing

Many articles on double stud walls suggest fiberboard or gypsum as the exterior sheathing to prevent winter moisture issues. Given that thick walls require higher cellulose density, what tricks are there to keep the sheathing from bulging?


Zone 5, Rochester NY

Asked By John Ranson | Apr 25 16
16 Answers

Best building envelope approach for an owner-built home in northern Wisconsin?

Setting the Stage:

My wife and I purchased a vacant farm (no buildings) with a south-slope in far Northern Wisconsin and have been planning our next home for a few months. We would like to build a "pretty good house" that finds that happy place between great energy efficiency and economy. This would be an owner-built home on a basement foundation. Our forest has plenty of millable pine and oak that we intend to use as much as possible for the build (framing, siding, flooring, etc.).

Asked By Michael Sterner | Oct 17 16
11 Answers

Bottom edge of rigid foam on basement wall

I'm going about installing 2" or 3" of XPS 4x8 sheets on my basement walls and then installing 1x3 firring strips across the top. I'm wondering if I should bring the foam all the way to the basement floor, or leave a gap and fill the gap with expanding foam. My vote is the first method, but I think maybe the gap with expanding foam may be a tighter seal.

Asked By Nicholas C | Oct 18 16
3 Answers

What's the best all around roofing/insulation solution for Zone 5?

Hello to the community. I am in northern Nevada zone 5. This is an arid valley with normally low humidity but it can get some really high winds... upwards of 80 mph. The house I just bought was built in the 70's. There is about 6 inches of blown insulation in the attic but none under the roof sheathing. I do plan on bringing the attic insulation up to at least R40. The attic has two small gable vents but zero soffit vents. The roof is completely failed cedar shakes with a lot of exposed sheathing throughout.

Asked By Roger Smith | Oct 20 16
14 Answers

Add rigid insulation to a 2x4 ceiling with an existing polyethylene vapor barrier?

I've been creeping around this website for years. I love reading random articles and questions and learning this stuff for fun.

Zone 6. We live in Southern Maine (Scarborough to be exact, stop by and say hi!).
Our "play room" appears to have been built (or renovated) as part of the garage addition, date unknown. Our house is 1960ish.

- (Section A) About 300 sq.ft. of the room is a flat drywalled ceiling, 8' tall. 2x6 framed ceiling. "Attic" space

Asked By Seth Fernald | Oct 3 16
2 Answers

Finding an engineer

I would like to put 8" of rigid foam over a gambrel barn roof, with long fasteners. However, I cannot find a standard guide to the numbers and spacing of screws for the roof. I was going to do screws every 12x12" (horizontally and vertically), but am concerned this may not be enough.

How do I go about finding an engineer to help calculate the appropriate quantity? This seems like a pretty specialized application, and I would want to use someone with experience. Is there a guide somewhere that lists names and numbers of companies who specialize in this area?

Asked By John P. | Oct 17 16
1 Answer

Can I use rigid styrofoam on top of top plate to minimize thermal bridge from trusses


I was wondering if its suitable to install a truss on top of a sandwich styrofoam between 3/4 ply and the top plate of an exterior wall, Sort of like putting a SIP on flat. Can the SIP support the point load of trusses for lets say a roof needing to support 100 psf?


Asked By Stephane Aucoin | Oct 17 16
5 Answers

How to air seal the attic floor to the wall sheathing?

I'm designing a house that will be built near Rochester, NY in zone 5. My primary air barrier will the plywood attic floor and plywood wall sheathing. What's the best way to seal these together? For structural reasons, I would prefer if the sheathing were continuous between the first floor and attic.



Asked By John Ranson | Oct 12 16
1 Answer

Detail for innie inswing door with thick exterior foam?

I'm planning a house for Rochester, NY, zone 5. The wall have 2x6 studs, 7/16 sheathing / air barrier, 4" rigid foam, a wrb, a 3/4" rainscreen, and 3/4" thick horizontal shiplap siding. The foundation is a monolithic slab on grade with 4" exterior rigid foam. The finished floor height is 2" above the slab. There are 4-7' overhangs over every exterior door.

My general question is, how do I install an innie, inswing exterior door in this assembly?

I want an inswing door because it can't be blocked by a snow drift.

Here are a few specific questions:

Asked By John Ranson | Oct 15 16
2 Answers

Installing exterior trim with a rainscreen

I'm planning horizontal shiplap siding over 4" of foam with a rainscreen gap for my house. How do I make the rainscreen accommodate exterior trim around the windows? Do I just make the furring picture frame wider than the trim, wide enough to support the ends of the siding?


Asked By John Ranson | Oct 14 16
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