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13 Answers

Foam sandwich in Canada

Hi Martin,

I have a question about upgrading insulation in our home we're having built in Southern Ontario.

The "normal wall" the builder uses is 1" of XPS rigid insulation on outside, installed over OSB, on top of a 2*6" wall on filled with R18 fiberglass bat. Naturally, the whole thing is sealed on both sides, with tape on the XPS and poly sheeting on the inside.

In Energy efficiency and durability | Asked By User-6930437 | Oct 12 17
2 Answers

Does repair work have to follow current code?

It’s always about the water, and codes.

Our roof design is a mess, and our gutters are overwhelmed. I can identify most of the problems*, but since I currently live in a condo, I can’t just work on the exterior myself or hire a competent roofing and gutter contractor. I need to work through the condo association management. I have two questions.

In Building Code Questions | Asked By andrew c | Oct 14 17
5 Answers

Best choice for LED lighting?

LEDs are solid state lighting and much like microchips advanced in efficiency/performance quite rapidly.

In Energy efficiency and durability | Asked By J M | Oct 13 17
1 Answer

Sealing up gaps in OSB exterior sheathing before insulating stud cavities?

My OSB sheathing on the exterior side of my exterior walls has many a gaps varrying from 1/8" to 1/4" as the proper installation instructions require the sheathing to be gapped with a nail to allow expansion due to humidity changes.

So...I'm looking at these gaps (some rather large) and getting ready to stuff mineral wool in. Should I take any time now to a.) caulk or b.) spray foam these gaps? I have a decent house wrap over the sheathing of course but that doesn't stop everything.

In Green building techniques | Asked By Nicholas C | Oct 13 17
5 Answers

Insulate basement ceiling?

Good morning everyone. Contractor is suggesting dense pack cellulose in conditioned basement (basement finishing job). Walls are insulated with cellulose/sprayfoam on concrete. Is this advisable? I've read not to insulate basement ceilings. Will it make it warmer in the winter? I'm in zone 6. This will obviously also help with sound dampening. Alternatives?

In Energy efficiency and durability | Asked By gi4ever | Oct 11 17
6 Answers

Flash & Batt Roof or Open Cell over Closed Cell roof assembly

I am building a 2000 SF house in Boston, Zone 5 with an unvented roof. In previous homes I have used 7" of closed cell foam. In an effort to provide a more economical hot roof,I am proposing to use 3" of closed cell foam applied to the underside of the sheathing and using an unfaced fiberglass batt below that with no drywall attached. My insulation subcontractor is proposing 3" of closed cell and then the remainder filled with open cell foam to achieve the R-value. Would either of these assemblies be safe or is it best to stay with the full thickness of closed cell foam?

In Energy efficiency and durability | Asked By Matt Murphy | Oct 12 17
15 Answers

Marine Zone 4 — Wall insulation — addition

Zone: Marine 4
Location: Seattle, WA
House Built: 1915
Square footage: 900 ft2 single story with 900 ft2 finished basement.
Wall height over basement: 12 ft
Current siding: Cedar, Paint in poor condition.
Insulation: not much, some fiberglass bat stuffed in nooks and crannies as they opened walls in the past. And dirty so there is plenty of air gaps.

GOAL: Comfort

In Plans Review | Asked By User-6933356 | Oct 11 17
9 Answers

Should I insulate between outer block and inner stud walls?

Like so many others, I have been given conflicting advice from "experts" in the insulation industry and I am now completely confused. I am building a two story home in zone 3 (montgomery, alabama). The external walls were done with concrete masonry units with cavity's filled with pumped mortar. We then came to the inside and completely framed leaving 1/2 inch gap between framing and exterior block walls. We eventually plan to coat exterior of block walls with spray on portland, but that could be in all honesty at least a year down the road.

In Energy efficiency and durability | Asked By IndenturedContractor | Oct 13 17
14 Answers

Who has a favorite heat-pump water heater?

We are now underway with our "pretty good" house here in southern Oregon and I am committed to the hybrid heat pump water heater concept for our 2100 sq ft, three generation house. With four adults and a grandchild in the house, I felt that an 80 gallon unit would be desirable. We plan to locate the HPWH in a centrally located laundry room which is just under 700 cubic feet and have plumbed a floor drain into that room for condensate or tank failure (hope NOT). I had been inclined to go with the GE GeoSpring but I have heard a rumor that GE is going to discontinue manufacture.

In Green products and materials | Asked By Alan Hart-McArthur | Oct 13 16
62 Answers

Another crawl space in the Northwest

Hello all, I have a 1150 sq ft rambler house in Fall City, Washington (near Seattle), zone marine 4c. I am currently in the process of redoing the crawl space. I have pulled the damaged and rodent infested insulation down, and removed the town vapor barrier. It seems I had some rodents that were digging past the foundation and getting into the crawlspace, ruining everything.

In Energy efficiency and durability | Asked By David Meyer | Nov 28 16
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