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2 Answers

Struggling with how to use foam on walkout over Canadian shield zone 7

I'm building a walkout basement (1000 sq ft) in zone 7 (NW Ontario Canada) and have purchased 1000 sq ft EPS at 5 inches and 1000 sq ft at 1 1/2" XPS (I was told its much better to use above the XPS since its much more rigid when walking on during the pour)..
I am struggling on how to best use the foam on the walkout side (I got a great deal so I have lots of EPS and XPS)..

Asked By tim brown | Aug 18 15
1 Answer

Wood burning stove below - what to do?

I live in an 1883 2-story farmhouse that was converted into 5 small condos in 1983 complete with wood burning stoves. Four of the units have had the stoves removed. The unit below me still has it and I swear smoke comes into my place when they use it. City allows except for occasional Action Days of no burning. I told the unit owner but she is out of town so I can't call her to come in and see for herself.
What would you do? Is there a way for me to test for smoke particulate? Picture attached -

Asked By Mary Schwaba | Oct 6 15
1 Answer

Why does opening the HVAC closet door affect duct blaster number?

Recently I conducted a duct blaster test on a house with an interior HVAC closet. While conducting the test I had accidentally left the door to the closet open. After doing all my sealing on the system I tested the ducts again only to find the number hadn't changed. However when I closed the HVAC closet door the number miraculously dropped. Now this closet is where the air handler is located sitting on top of a box built return so there is no way that I can see how shutting this door can effect the duct numbers.

Asked By Benjamin Barker | Oct 6 15
8 Answers

Cut and Cobble


This is a follow up to my original post seen here:


Getting ready to begin this ceiling insulation project using the "cut-and-cobble" method. I have a few more questions.
1. would it be better to use XPS product or something like R-Tech?
2. I will be using can spray foam for the gaps, but how do we attach to underside of the roof sheathing?

Asked By Rob Henderson | Oct 3 15
16 Answers

Anyone familiar with Insultex house wrap?

I was wondering if anyone had any thoughts on this house wrap - http://www.insultexhousewrap.com/

They appear to be making some exaggerated claims and I am not certain that the R-value claimed would be possible.

Any thoughts?

Asked By Marcus Sheffer | Jul 31 15
15 Answers

Double Stud Wall sheathing and vapor barrier


I am building a 10" thick double stud wall that will be dense packed with blown in cellulose. I live in Virginia in climate zone 4 in a mixed-humid climate. I am worried about warm air getting into my wall cavities and possibly condensing on the cold sheathing during the winter months. I have been thinking about my different options and was hoping to get some advice on each option.

Asked By Jimmy Nguyen | Sep 30 15
4 Answers

Insulation advice

Sorry to repost this ? But we are over wellmed?
Just got some prelims back and he's want to know about insulation details so they can be noted.
Zone 3,12/12 pitch standing seam roof with 5/8 plywood an clips,2 story with a option I bonus room on the third,it has a half story truss,24 on center,we were thinking about spray foamin the inside roof line but know if that the best option.
Walls are 2x6 on 24 centers,we planed on putting 1 inch exterior foam board under hardie board and over tyvek and osb but don't know if that's te best option.

Asked By Quinton | Oct 4 15
1 Answer

Sure ext foam when blowing wall cavities might be good idea, but is it NECESSARY?

My 1920 platform framed home is on the border of climate zone 5&6.

The empty wall cavities are framed with true 2x4s, 16 OC. Walls are covered with lathe and horsehair plaster on the inside and 1" pine sheathing boards outside. The current siding is a horrendous installation of vinyl over the original clapboards. The cavities are now empty.

We intend to remove the vinyl (carefully, for reuse), strip the clap boards, dense pack the wall cavities, wrap the house with tar paper and flashing details, and rehang the vinyl. Not sure about resetting doors and windows.

Asked By Mark Baker | Oct 5 15
2 Answers

Sight-built Sips detail--leave the middle foil face?

As a follow up question to a previous one:

I am going with the "sight-built sip" approach.

Zip sheathing taped then a double layer of 1" eps foam and 1/2" osb on the outside with an additional layer of building wrap.

The sheets came foil faced.

Q:Does it matter if I leave the foil on the 1" layer attached to the sheathing? (sandwiched between the 2 layers of foam) Will it interfere with moisture flow away from the house?

It peals off fairly easily so that is an option.


Asked By Brian McDonald | Oct 5 15
2 Answers

How is thermal bridging prevented?

The construction process of our home, in southeast Iowa, was completed in January 2014. The house has fiber cement lap board siding and an interior spray foam insulation. In March of 20014 we noticed moisture accumulating, in a vertical line pattern, on the east elevation of the house.

Asked By S. Schneider | Oct 5 15
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