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4 Answers

Methods for air sealing the ceiling

Hello,

We are building in a cold climate, zone 7, using ICF walls. Because the walls are ICF, they act as an air barrier, but I'm trying to figure out the best way to air seal the ceiling. Based on what I've read on this site, I'm following a few guidelines:

  • Ceiling will be flat, using energy heel trusses
  • Using blown in cellulose, thinking around R-60
  • No recessed lighting (thanks Martin)
Asked By Nick Hall | Aug 28 15
10 Answers

XPS or PVC under base plate

I'm looking to start framing in our basement. The house is 15 years old, and did have some water leakage (some small puddles could form during big rains... We had crack injections done this fall to alleviate the issue), but no flooding yet (knock on wood).

I thought I read somewhere that you could use XPS insulation to put under the base plate of the wall. It seems like a good idea (a 1" insurance policy should the basement begin to flood).

Asked By Andrew Wayland | Feb 22 15
4 Answers

REMOTE walls using Roxul products

I've been on here previously to gauge everyone's thoughts on the building plan for our new house, and I was curious about the opinions out there on what we are currently thinking. We're building in northern Oakland county Michigan climate zone 5. The house is a 2357 sq ft ranch with a walkout basement. We've considered just about everything, but here's where our heads are at the moment:

1) I think we like the idea of doing superior walls for the backfilled foundation walls, with the exposed walls being wood framed (for ease of attaching cladding and framing windows and doors).

Asked By Brian W | Aug 30 15
14 Answers

How to build a gabled roof on a rigid insulation roof?

Hello to all at this forum. Back in 2013 I posted on my garage build here....

http://www.greenbuildingadvisor.com/community/forum/energy-efficiency-an...

Since a few months now I had started doing some work on my home to increase the insulation value.

I am including a photo of how it is today just before we add the roof sheathing, but I am sort of stuck on how to include a gable roof on each end of the house.

Asked By Leon Stepanian | Aug 17 15
4 Answers

Rim joist foam and termites

I'm not sure if this would fit better 'Energy Efficiency and Durability' category, but I have a few questions about using foam to insulate rim joists. From an air-sealing and thermal performance perspective foam seems the clear choice. I've read Martin's FHB article and spray foam and cut-and-cobble approaches make sense.

Asked By Jeffrey S | Aug 24 15
2 Answers

Extra furring strips into OSB only

I was recently snooping around a house under construction by Habitat for Humanity in Traverse City Michigan. The house is frame 24" o.c. and has two layers of 2" XPS foam (4" total) over the OSB sheathing. In addition to furring strips over each stud, they have attached furring strips between each stud such that there is a furring strip every 12". As far as I could tell, the only thing these additional furring strips could attach to is the OSB. Does this make sense?

Asked By Reid Baldwin | Aug 28 15
2 Answers

Basement cement floor as shower pan

Our planned basement shower pan is a 5' x 5' area of the poured concrete floor, sloped on all four sides to a central drain and sealed.

This isn't a normal request for a concrete contractor, I'm sure. Has anybody our there done it this way? Are we setting ourselves up for trouble?

(By the way, Plan B is to have the contractor drop the floor a couple of inches in this area and have the tile guy build a conventional mortar bed, Kerdi waterproofing and tile shower pan.)

Asked By Esther Streusand | Aug 27 15
3 Answers

Opinions sought on window details

Building a "good" house in zone-5.

Current plans are to use 2x4 framing with plywood sheathing, then two 1" layers of reclaimed foam, 1/2 thick furring for a rain screen and hardiboard siding.

I have a builder willing to do this and we are discussing window details. The windows are 5" thick and come with either an installation fin in the middle or no fin and you use straps to attach the windows.

Asked By Michael D | Aug 27 15
5 Answers

Exterior door details with 4" thick foam walls

I've read plenty of articles on Dudley boxes and setting innie and outie windows, but doors are a whole different animal mainly due to the swing and bottom. The sides and top are basically the same details as a window to my understanding. It may be possible there is a manufacturer that makes door settings this wide that are affordable? The wood on all of the original doors is rotting because they were set 3" off the finished grade and got wet always. The foam will be 4" in areas and the walls are either 2x4 or 2x6 depending on the area of the house.

Some of my questions and concerns are:

Asked By Michael McArdle | Jun 3 15
2 Answers

Yet another basement question

First, let me just say THANK YOU for this wonderful resource. The advice and analysis you give here is priceless and it is just a pleasure to read through the posts here.

Asked By Corey Vanhove | Aug 24 15
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