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3 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
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
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

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
2 Answers

Unknown Insulation?

Hello All, I have been doing Energy Audits in upstate NY for almost 8 years and am rarely stumped but this ones got me.. I was doing an audit on a 1930's Bungalow and just cannot figure out what type of insulation this is/was.

Asked By Paul M | Oct 5 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
1 Answer

Ductless heat pumps and conditioned crawl space

Any suggestions for using the two together? I'm intrigued by the efficiency of the DHP's, but don't know how I can get some of the conditioned air into the crawl space without auxiliary fans or such. Thank you for your help.

Asked By Philip Joyal | Oct 5 15
10 Answers

Value of Phase Change materials

Our passive solar house was completed in June of this year. I designed it using principles learned on this web site and Fine Home Building magazine. I followed somewhat the Pretty Good rules found on this site and a great deal of input from the Energy Nerd blog.

Location is Bellingham, Wa north of Seattle right on the Canadian border.
10-20-40-60 insulation.
Triple glazed windows with a good solar gain. Approx 8% window to floor ratio.
Overhangs to provide appropriate shading. South facing.
Double wall, advanced framing. ACH 1.0.
HRV and a mini-split.

Asked By Stephen Carlton | Oct 4 15
4 Answers

Strong odor after crawlspace encapsulation

We had our basement encapsulated in the fall last year and made it through winter no issues. They used a thick mil high quality (apparently) vapor barrier and then sprayed /fogged with mold preventative. I don't think there is any more mold - smell is not musty really and I don't get a mold allergy reaction.

Asked By jeff weikert | Jul 22 14
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