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1 Answer

Patio roof on top of insulated roof detail?

Zone 4A, hip roof with 4:12 pitch; spray foam insulation to be on the interior side of the roof deck (not ventilated). I will be adjoining a new roof out over a patio, placing the new ridge and rafters on top of the existing zip sheathing . The patio roof will have exposed rafters, and the wall of the house will extend up to the new ridge, so the part behind this vertical wall that joins with the existing roof will create a dead space.

Question: is the dead space between insulated roof deck and addition an issue?

In GBA Pro help | Asked By David McNeely | Apr 29 16
7 Answers

Why are my windows wet?

4 year-old 2800 SF home in Duluth (zone 7A). Very tight construction, Well insulated etc. Using a Venmar HE1.8 HRV running full blast. We still have 1-2 inches of condensation and some ice along the bottom of our windows when the temp is <0F at night. (low-E H-windows).

Is our HRV sized too small, or am I doing something wrong?

In Mechanicals | Asked By Jeffrey Lyon | Dec 11 13
2 Answers

What is the safest (healthwise) roller blind I can buy?

What materials would it be made of. I can find one made of linen but with an acrylic foam backing.

In Interior design | Asked By Angela Weber | Apr 29 16
2 Answers

In process of utilizing 5/8" fiberglass shell for a small building

Is wrapping in EPS or XPS advisable; should foil surface (vapor barrier) face inward to building or outward to ambient? Is Ceramic Paint a viable alternative since Fiberglass Shell is a homogeneous structure. Electrical and plumbing to be installed on interior side of shell. if so referral to independent (i.e ASTM) applicable studies is appreciated...Thank you, Tim

In Energy efficiency and durability | Asked By Tim Boyle | Apr 27 16
8 Answers

Insulating exterior wall where it meets partition wall

NH here.

I was planning on using rigid foam insulation in a stud bay where a partition wall for a shower begins.

The rest of the bays use un-faced fiberglass batts and a plastic sheeting as a vapor barrier.

The exterior wall is OSB.

I want to go with the rigid foam because I feel it will be easier to piece around the framing I am adding in the bay to support the partition wall - going above and beyond to make sure there is no movement (in aspects I can control) given that the wall will be tiled.

In General questions | Asked By Sam Smith | Apr 9 16
7 Answers

Does PVC really offgas sufficiently to be a concern for ventilation returns?

Just wondering...does PVC pipe really off gas sufficiently to be a concern in the supply air returns of HRV/ERVs?

In General questions | Asked By Eric Mikkelsen | Apr 28 16
2 Answers

Best adhesive for Visqueen lapped to concrete block?

Looking for an adhesive to stick my 6 mil visqueen vapor barrier to the concrete block stem wall. I want to lap the visqueen up about 6 inches. I have tried duct mastic which sticks well to the block but readily peels from the visqueen. Something other than Tremco?

In General questions | Asked By Robert Holland | Apr 28 16
3 Answers

Hot water to toilet

Hi, I had this idea that I could purposely run the hot water to the toilets in the home to help heat the small bathrooms which by design have no supplemental heat source except a ceiling heat lamp on a timer. The homes are 900 sq.ft single heat source via direct vent gas wall heater (Rinai). My question is why not use a bit of hot water to heat up the toilet and create some extra heat for the bathroom and make a nice warm seat.

In General questions | Asked By MURRAY bANTING | Apr 28 16
2 Answers

Ways to cool in Hawaii

Hello, I'm in a zone-1 area, specifically, the Leeward side (hot dry!) of Oahu. My house was built in the 80's, has minimal to no insulation and none in the attic, and only has window-unit AC (mounted in the wall). I prefer not to use the AC when at all possible, but as the summer comes on, it ends up getting hotter inside than outside with a breeze despite having the windows and garage open.

In General questions | Asked By Josh Lavender | Apr 28 16
44 Answers

Inexpensive exterior insulation stand-off — Critiques?

I am trying to come up with some inexpensive, and sensible details to accommodate a 6" layer of exterior Roxul Comfortboard IS comprised of two layers of 3", 2' x 4' batts. See attached PDF for details. My concern is that with such a substantial thickness of Comfortboard, the potential for faster "sag" through this, or durability issues during seismic events is problematic. On many of our projects, we have screwed our vertical cedar 1x3 rain screen material directly through a single, thinner layer of the Comfortboard directly into the framing.

In Green building techniques | Asked By Burke Stoller | Apr 19 16
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