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2 Answers

Flooring on top of under-insulated slab

Our new home will have 2" of rigid foam under the basement slab and a poly vapour barrier. We are using cork plank flooring for 90% of the floors and tile in the washrooms. Given that the concrete itself contains moisture and the cork manufacturer states a vapour barrier must be used over concrete what is the most cost-effective method to install the flooring? I am considering a dimpled membrane like Delta FL and installing the cork directly over top or possibly 1" rigid foam and again installing directly over top.

Asked By Shaun Malmo | Jul 23 13
7 Answers

Is radiant cooling a more efficient alternative to forced air?

I am planning to build a home in Phoenix, Arizona, and have been looking into creating ceiling tiles that act similar to radiant floor heating. From the information I've gathered humidity is a main reason against it. However Phoenix is very dry with a low dew point.

Asked By Daniel Houston | Jul 15 13
6 Answers

Supply-only whole house ventilation

All the whole house ventilation systems I read about are exhaust only. I am thinking about supply-only ventilation. Is there any reason not to do it this way?

Asked By Mark Thomas | Jul 1 13
7 Answers

Fasteners for mineral wool to foundation walls?

I am planning to insulate the exterior walls of a building with a walk-out basement. The building will have wood studs for the first floor and concrete walls for the basement.

Originally I was planning to use ICFs below grade and foam board above, but became concerned about possible damage by carpenter ants and the need to install gypsum board on the interior.

Asked By Stephen Martinson | Jul 16 13
0 Answers

Porch Roof Skylight

I'm looking for suggestions from the GBA readers for a cost effective way to let some light in through a farmer's porch roof. I am currently in the process of building my house which includes a farmers porch on the front/south face of the building. The roof is in front of the kitchen and dining area. I'd like to add some light to these rooms, particularly in the winter but block unwanted solar gain in the summer. My initial thought was to install a skylight and locate it strategically for solar gain in the winter but not in the summer.

Asked By Brian Beaulieu | Jul 22 13
3 Answers

Ice damming above cathedral ceilings

I have a 1973 home with cathedral ceiling, And I have ice daming. If I remove the shingles and plywood, seal all air leaks, install high density insulation batts, with baffles for ventilation would this solve the problem. I believe I only have 2'x8' space in the ceiling, Wood ceiling on the inside attached to plywood.

Any suggestions?

Asked By Dave Heinzelman | Jul 22 13
14 Answers

Zone 5/6a Vinyl Residing - Double Blueboard, Wrap?

As a follow up to:

Dow SIS is not available in this area, so we will insulate the walls as they are:

kraft faced fiberglass insulation (very, very thin)
two 1/2" layers of fiberboard as sheathing
one 1/2" layer of blueboard

My thought is to dense pack cellulose in the walls, tape the existing blueboard, add a second 1/2" layer of taped blueboard, possibly wrap, then side.

Asked By J Heckmann | Jul 14 13
2 Answers

Interior sheathing with outsulation?

I am designing and building a tiny house on wheels (in climate zone 6) and the wall assembly I have come up with is a little bit unconventional. I would like to use the PERSIST method, but due to size limitations this is not possible. The wall section I have come up with is a little like PERSIST though:

From interior to exterior:
-7/16” OSB (sheathing & interior finish – applied using caulk)
-2x4 wood studs @ 24” o/c filled with 3-1/2” XPS
-3” XPS over the studs
-Solitex MENTO 1000 WRB (38 perms) -taped continuous air barrier
-vertical ¾” furring strips
-open joint timber cladding

Asked By Travis Marttinen | Jul 20 13
1 Answer

How to best insulate and vapor barrier Room in Attic Truss?

I live in zone 7 Alaska. We have built at 24' x 42" detached garage/shop with Room in Attic Truss. The roof pitch is 10/12. The trusses are 24" OC. The top chord of the truss is a 2x6, but we've furred it out where the top chord defines the interior ceiling, so essentially we have 7" of room to insulate in the this part of the roof. The "wall" of the attic truss is 2x4. The roof consists of OSB, underlayment , 4" of Rmax, OSB, then shingles. we have also wrapped the walls of building with 2" of Rmax.

Asked By Heather Floyd | Jul 20 13
1 Answer

Insulating with exterior foam and cladding choices

We are having a home built in Gunnison, CO, a dry, high altitude climate. Annual precipitation around 10" with summertime highs around 80 (no air conditioning) and wintertime lows down to -30 degrees Fahrenheit. Currently, we have 2x6 walls sheathed in OSB. We plan on a wet spray application of cellulose in the wall cavities and adding foam to the exterior. My question is, what is the proper order of layers on the exterior wall after the OSB? We would like to use 2-3" of foam with a traditional

Asked By Theresa Hanacek | Jul 20 13
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