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1 Answer

Concerns about backdraft and make up air

We're in the process of air sealing a mid-Atlantic house built in the mid-80s. (Today is a humid 94 degrees and in the winter we go below freezing.) We had low CFM-rated (OKNA-brand) windows installed recently. After we seal the rim joists and the attic, I am concerned about what make up air and backdraft situation will be. We will be installing a 300 CFM range hood soon, too. Our water heater was just replaced with a power vented model, and we expect to replace the furnace very soon. We do have a wood burning fireplace.

Asked By Forum User | Sep 3 15
1 Answer

Is this a risky wall assembly?

I am in the process of finalizing plans for a 2 story 2385 square foot home in Zone 6 WI 44.3353° N, 88.6389° W. I have been trying to get in the pretty goodish house category as far as insulation levels and while not where I'd like them to be am currently sitting with the following setup due to budget.

R10 EPS below slab insulation
R10 EPS exterior Foundation walls (will finish off basement later and can add interior insluation)
2x6 R20 damp spray cellulose with R7.5 Atlas Thermalstar LCI-SS EPS insulated sheathing
R55 blown cellulose attic insulation

Asked By Jeremy Coenen | Sep 3 15
3 Answers

Vented attic vs. a sealed, non-vented, airtight attic

I'm building a new home in Miami, Fla.

An insulation contractor advises me to eliminate the planned roof & soffit vents and seal the attic with foam.
What are the Pros and Cons for maintaining attiic ventilation, and eliminating it?

Asked By Calvin Smith | Sep 1 15
6 Answers

Penetrations in exterior foam and rainscreen

I will be installing 3 or 4" of exterior foam with a 3/4" rainscreen and installing new windows and siding. This will be my first retrofit of this type.

Asked By Brian Otten | Sep 3 15
10 Answers

Is it OK to step the slab thickness over the footings to accommodate insulation between the slab and the footings?

I am building an addition on my home near Ottawa and I am adding two new sections of full-foundation on either side of the existing foundation, which has no under-slab insulation. I am adding 3 inches of insulation under the new slab, however for various reasons it is not practical to bring the 3 inches of insulation over top of the footings and right to the inside edge of the foundation wall.

Asked By Chris Seligy | Sep 2 15
11 Answers

How can I properly vent my tiny house roof (it has cross member framing instead of rafters)?

I have the framing almost complete on my tiny house, but I have run into a stumbling block. Framing the roof with cross members instead of traditional rafters made a lot of sense because the shorter span allowed smaller lumber for more head space and less weight, but upon further research my plan for venting is not going to work (I know - proper planning prevents poor performance). See attached picture for framing structure.

Asked By Ryan Reed | Sep 2 15
4 Answers

New 20+ SEER Variable Carrier heat pump w/ Greenspeed Intelligence system creating moisture & performance problems in the crawl

I had to replace 2 -13 SEER HVAC split systems in my house about 2 years ago do to some Sandy storm damage. One split system was a 90% gas furnace with a 3 ton 13 SEER AC and the other was a 2 ton 13 SEER heat pump.

Asked By Bruce Howe | Sep 2 15
5 Answers

Building codes

I often see posters refer to building in areas with no codes. Here in Canada, although we have areas in which there are no permits or inspections, the building codes are enacted to cover the whole of each province or territory. People building in areas where the codes are not enforced have the same obligations to follow them as elsewhere.
Are there areas in the US where there are no codes and you are free to build as you like?

Asked By Malcolm Taylor | Sep 2 15
1 Answer

Can construction foot traffic on the roof dislodge or break the seal between the foam and the sheathing?

I am having the underside of my roof (flat roof-1/4"/12) sheathing sprayed with 2" of closed cell foam (flash/batt). I am concerned that construction foot traffic on the roof will dislodge or break the seal between the foam and the sheathing. There is quite a bit of flex in the roof sheathing. Is my concern valid?

Asked By keith messick | Sep 3 15
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