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4 Answers

Zone 3 minimum wall assembly

New construction proposed 2x4 wall assembly.
Latex paint, 1/2" Sheetrock, BIB fiberglass, OSB, Tyvek wb,1" gap, stone or smart siding.
Doesn't this just meet the minimum requirements in Zone 3?

In General questions | Asked By Mike Beckham | Oct 22 16
15 Answers

can you create a blog on infrared heating panels?

People would benefit from knowing how infrared heating panels are more efficient, comfortable, and safer than conventional heating methods.

In Energy efficiency and durability | Asked By Iona Jonasson | Oct 19 16
4 Answers

Zone 3 roof dampening concern unvented attic

New home construction - roof design
asphalt shingle, 30# felt, OSB, 5 1/2" open cell foam. Should I be concerned about the design causing moisture problems over time?


In General questions | Asked By Mike Beckham | Oct 22 16
17 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.).

In Green building techniques | Asked By Michael Sterner | Oct 17 16
6 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

In Green building techniques | Asked By John Ranson | Apr 25 16
6 Answers

Garage and root cellar insulation

I received a call from my mechanical engineer today asking me how I planned to insulate the garage and root cellar ceilings. Both rooms are in the basement and above those ceilings are first floor living spaces. I told him my plan is to dense pack them with cellulose and probably add an inch of Polyiso covered with a layer of gypsum to break the thermal bridge and satisfy fire code. I was planning on insulating the rim joists with a couple of inches of ccSF on the inside, the only area in the house with the nasty stuff, mineral wool on the outside, and then dense pack would fill the bays.

In Energy efficiency and durability | Asked By Jonathan Lawrence CZ 4A New Jersey | Oct 19 16
7 Answers

Double backdraft damper needed for bathroom fan?

I am going to install Panasonic exhaust fans in our bathrooms in new construction through an unvented attic.. The Panasonic fan comes with a built-in damper and their installation guides mention using a wall cap with a damper too. This means there are two dampers.

The Panasonic damper is very light plastic does not seal well and opens easily. The wall cap damper is typically metal, making it a little harder to open. Our HVAC contractor suggests not using a damper at the wall cap but this worries me.

Is the best approach to use two dampers in line?

Thanks for your advice.

In Energy efficiency and durability | Asked By Jeremy Turner | Oct 19 16
7 Answers

Concrete floor caulking is failing... why and how to fix?

My polished concrete floors are about a year old. Now I see that the caulking the contractor laid in the seams is starting to crack and split (see photo). The splitting appears to be occurring more often in the part of the floor that gets sunshine.

Anyone know why this is failing so soon? Was the wrong material and/or technique used? What is the fix? Thanks.

Port Townsend WA

In Green products and materials | Asked By Steve Hengeveld | Oct 21 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.

In Green building techniques | Asked By Nicholas C | Oct 18 16
12 Answers

Unventilated, highly insulated roof — replacing shingles

We are replacing the shingles on a cathedral roof.

The roof has been insulated from the inside. 8 inches of expanded polystyrene below the roof deck including cut and cobble between the rafters, and 4+ inches of additional eps and mineral wool below that.

The roof is not ventilated.

The shingles will be asphalt.

From what I have read, asphalt shingle roofs are not water or vapor permeable, so using a permeable underlayment will not provide a benefit, because vapor will still not be able to dry through the shingles.

Two questions.

In General questions | Asked By Sharon Secrist | Oct 20 16
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