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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

Sure, exterior rigid foam when blowing wall cavities might be a 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 in tar paper, and rehang the vinyl.

Asked By Mark | Oct 5 15
5 Answers

Insulation advice

Sorry to repost this, but we are overwhelmed.

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
7 Answers

Solar hot water system with oil heat, one hot water tank or two?


I'm wondering if someone could help me. I am very new to the site so I apologize if I have missed the answer to this question in the archives.

We have a solar hot water system (geothermal, installed 2007, has already paid for itself - I have read the articles on photovoltaic systems) in a house that has oil heat. [Editor's note: Audrey later clarified these remarks by noting that the reference to a "geothermal" system is erroneous; the intended reference was to a solar thermal domestic hot water system.]

Asked By Audrey | Oct 5 15
3 Answers

Vapor barrier in attic?


Asked By Lucy | Oct 4 15
17 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
2 Answers

Is there a compatible spray foam to be used with Type IX- EPS foam?


Asked By william dempsey | Oct 6 15
2 Answers

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
5 Answers

R-values - are they different depending on direction of heat flow?

I have a contractor claiming that their reflective insulation (alarm bells, I know!) has a different R-value for downward heat flow than upward heat flow. Is that possible?

The material is intended to be installed under the roof shingles. I spoke to the manufacturer and he assured me that the reflective property doesn't work when in contact with asphalt shingles, but that the product has an acceptable R-value for "downward heat flow" to be eligible.


Asked By Whitney Larsen | Oct 5 15
23 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
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