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18 Answers

Can a foundation drain to daylight double as a radon vent?

Ok this is probably a dumb question, but I'm looking at putting in an addition this spring, and was looking at ways of draining it and stumbled onto radon mitigation. So now I'm not sure how it would all fit together.

Asked By Terry Sharpe | Dec 15 15
1 Answer

Floor register location in relation to the return register

Hello all,

I have been working really hard to finish up a Florida renovation, but I have ran into another small hurdle. I have floor register (2-1/4x14) that will be installed over hardwood flooring and high wall return register(10x10) in each room. One room in particular, a 13'-9"x 9'-10" room, the 7in duct is positioned to a have the floor register directly across from the return register.

Asked By Jimmy Miller | Dec 18 15
18 Answers

Calculating the ROI of polyiso under siding vs. just doing PV instead

My pre-war Cape is getting more and more livable and less expensive to heat (I am about 1/4th the cost from when we dumped oil and got heatpumps). I got airsealing and attic blown in with cellulose last year by MassSave. They did dense pack rafters behind knee-walls and brought them into house thermal envelope, thought those areas of the roof are now unvented, so there is that.

Asked By Apollo | Dec 14 15
3 Answers

HRV/Air exchanger connections with forced air duct system and interlock

Hello, I recently bought a townhouse (2 stories + basement). There is a furnace and a heat pump (HVAC system) and there are ducts everywhere except the basement.

I want to improve ventilation using an HRV. I had several ventilation specialists come in and they all seem to think that putting in separate ductwork is not a consideration in my house. They all seem to suggest attaching the HRV unit to the furnace.

Asked By Mikhail Kadychevitch | Dec 15 15
1 Answer

Proper venting for 12 pitch hip roof with soffits on only 2 sides

My 3rd floor was already a finished, conditioned living area when we bought the home. The furnace that was located above the ceiling joists had to be removed. Upon removal of all plaster and lathe we discovered that not only is there no ridge vent but only the front and back of the house have soffits (which are vented). There was blown in insulation above the ceiling and batts on exposed roof slope and behind knee walls.

Asked By Anne Thies | Dec 12 15
8 Answers

SIP rot and remedy

I have had to recently address a SIP panel issue, installed 7 years ago, on a timber frame building. The issue being, that the spline joiners between the panels, seem to have had a "chimney " effect resulting in moisture/heat travelling to the peak area. Combined with a butyl membrane encapusulating the entire exterior surface, the SIP's had zero permeability for the panels to breathe. The equation ended up with roof rot of the exterior SIP's OSB panel, and rot of the joining headers.

Asked By Mark | Dec 2 15
4 Answers

Vinyl siding over rigid insulation

I have a multi family project that needs to be resided. Unfortunately we cannot afford to use cement board siding and are using vinyl. Is it possible to attach vinyl directly over rigid anchoring to the sheathing? It doesn't seem to be an acceptable attachment method from the vinyl siding manufacturers. Is it worth installing sheathing over the rigid, perhaps a taped zip system? Thanks.

Asked By Julie | Nov 25 15
7 Answers

ComfortTherm plastic-enclosed batting above radon retarder sheathing in crawlspace?

I have encapsulated my crawlspace (5-7' tall walls) with proper poly I got from radon mitigation specialist. Everything all the way to band joist is encapsulated. I also have good above code level ventilation going between crawlspace and basement. Basement walls I was able to cover in polyiso, but I don't have large enough access hole to the crawlspace to get even 1/4 size sheets of polysio.

Would attaching ComfortTherm plastic-enclosed batting work in that kind of situation? I am in Zone 5.

Asked By Apollo S | Nov 30 15
21 Answers

ZIP R-Sheathing Climate Zone 5?

I am considering ZIP R-sheathing for a home in Climate Zone 5. The wall assembly would be a ventilated rainscreen as follows (exterior to interior)

1. Hardie Panel siding
2. 3/4" furring/airspace
3. ZIP 1.5" R-sheathing (R6.6 total, 12-16 perms for the OSB, <1.0 perm for the polyiso)
4. 2x6 studs
5. Icynene Low Density (5.5" thick R-20, 11 perms)
6. 1/2" gypsum

Asked By Joseph Yount | May 12 15
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