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7 Answers

SIP walls insulating the floor joists

I'm attaching a picture posted by Insulspan, the SIP manufacturer we're getting a quote from. It shows the SIP wall on the edge of the basement wall with the floor joists on the inside edge, providing continuous insulation of the rim joist. Has anyone seen this done? I thought at least 4 inches of the floor joist had to rest on the basement wall to be structurally sound. I plan on using superior walls which are 10.25 in thick and 8.25 in SIPs.

Asked By Brian W | Nov 28 15
1 Answer

Detail on a garage wall abutment to an exterior block wall

Hi there - been using this site for about a year. Just performed an energy retrofit where I ripped out the ceiling in the garage Redid the ducting system, fixed a lot of electrical that was wired incorrectly or unsafe, airsealed, put ithen put in two layers of 1/2" polyisocyanurate, covered with 1/2" drywall.

If you follow this link: http://www.greenbuildingadvisor.com/cad/detail/air-barrier-garage-band-j...

that is exactly the configuration i built to (I did not use furring strips like the detail calls out though).

Asked By Daniel | Nov 29 15
2 Answers

Where to put the smart vapor retarder?

We are remodeling the second floor of our 1956 Cape in Williamsburg VA, climate zone 4. I need advice about where to incorporate the MemBrain smart vapor retarder in the roof and wall insulation stack up.

Roof stackup: Asphalt shingles- Durabuild synthetic underlayment-1x8 plank roof decking- approximately 1.5 inch airspace (ProVent running soffit to ridge vet)- 3.5 inches of Roxul R15 between the 2x6 rafters- 5.5 inches of Roxul R23 between 2x6 “mooney wall” furring running perpendicular to the rafters- sheetrock.

Asked By Chris | Nov 29 15
1 Answer

Source for rock wool batts in Albany, NY area?

I am interested in using Roxul or other rock wool peoduct in bith batt form and board form for my build in Saratoga County NY, near Albany. Is there anyone here that can recommend either or both a source and an installer in this area?

Asked By Joe | Nov 29 15
1 Answer

Unvented attic and wall?

Zone 3, 12/12 pitch roof, Galvalume color roof.
Talked to insulation contractor and discussed options.

2x6 walls = Hardie lap siding, 3/8" rainscreen, Tyvek, OSB, air sealing, BIB insulation (R-23), 5/8" sheetrock.

2x8 cathedrial roof, unvented, with total elect units and ducting in kneewall area and spare room in the center = standing seam, membrane?, 7/16" OSB, 2 inch polyiso, membrane or taped joints?, 7/16" OSB, 7 inch open-cell or BIB insulation.
No venting.

Are we getting closer?

Asked By Quinton | Nov 29 15
1 Answer

What is the most economical heat system for a 700 s.f. house with no furnace?

I have a relative who may have to give up her house due to illness/unemployment Her gas furnace went on the blink. To replace it would be $1800 +. What is the safest most economical method of heat to heat her 775 sf house. She closes off one room so actually 3 small rooms & a bath is what she would be heating. For now she is using an electric fireplace and two infrared heaters that are supposed to heat up to 1000 sf.
Thank you.

Asked By Ruby | Nov 30 15
1 Answer

Green / Passive House Architects

Anyone know of a good source for good energy efficient / Passivehouse architects?

Asked By Peter L | Nov 29 15
7 Answers

Insulating a non vented vaulted ceiling in Canada


I've recently had a 10x14 foot backyard studio built for me by a local company. I asked them not to insulate it because I was hoping to save some money by doing it myself. However, after some research I'm not really sure how to continue.

The studio has a vaulted 2x6 ceiling (with one skylight) with no ventilation. The soffits also have no vents. Initially, I was planning to just shove some fibreglass batts up there, putt up a vapor barrier and then finish it off with some wood paneling. However, after researching it sounds like that's a recipe for moisture and mold.

Asked By Kirsten Quist | Nov 28 15
1 Answer

Masonry block wall: To seal or not to seal?

In preparation to insulating my renovation of a 1970s building's masonry block wall with 2" XPS foam board attached directly to the masonry block, should I paint the interior masonry block wall with a sealer like DRYLOK® Masonry Waterproofer or KILZ 2® LATEX Low VOC?

Right now there is a thin coat of cheap latex paint on the block wall.

Russ :-)

Asked By Russell | Nov 29 15
3 Answers

Best practices for HRV on a budget

I am building a simple but efficient home in climate zone C4. It will be a 3 bedroom, 2000 sq ft home. with us living mostly in the upper half. I was originally planning on putting one or two panasonic spot ERVs in but am know thinking it might be better for overall air quality, efficiency, and spreading the heat from my two headed mini-split, to put a fully ducted HRV unit in. I have been looking at the Fantec FLEX100H, and the Lifebreath RNC 95. Money is a huge issue but the price difference between two panasonics and one of these units is not much.

Asked By Kail Zuschlag | Nov 29 15
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