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2 Answers

Heat sink to absorb heat from asphalt shingles (sealed attic)?

Creating sealed attic would prefer to avoid a vented nailed assembly etc. above deck and at same time find a way to use all that heat that the asphalt shingles absorb which shortens their life even more with a sealed attic.

So supposed there was some kind of thin mesh (or foil?) to put between the shingles and underlayment that would connect to one or two conduits that could divert heat away and maybe even be somehow connected to the domestic hot water system. Seems like those 170 degree summer peak shingle temps could be harnessed. (??)

In Green building techniques | Asked By David Goldman | Mar 31 12
6 Answers

Can you apply spray polyurethane foam over mold in a cathedral ceiling?

I am renovating my second floor bedrooms and plan to apply spray foam to the 2x6 ceilings (cathedral). The old batt and baffle system was not installed properly and there is some mold in the sheathing and the 2x6's. I've read that the heat generated from the spray foam kills the mold.


In Energy efficiency and durability | Asked By Jim Rogers | Mar 29 12
4 Answers

Dow SIS (Structural Insulated Sheathing) provide structural stability?

Does anyone have field performance data/experience with the Dow SIS (Structural Insulated Sheathing) product as it relates to lateral stability and transverse load? I've read the ICC reports but continue to be skeptical. Concerned about house creaking and racking, especially in high wind conditions.

In Energy efficiency and durability | Asked By DENNIS MCKENNA | Mar 24 12
2 Answers

Insulation of copper pipes

Regarding a new home in HH climate (2B) with non-vented attic. All ducts and pipes are within the conditioned space. No pipe in exterior walls. Copper pipe was used for pressured water service (1" and below), and it's routed overhead (attic, between floors, etc).

I insulated the hot water pipe with 1/2' thick polyethylene foam split tubes for energy conservation.The seams are sealed with self-sticking adhesive. The ends and fittings were sort of haphazardly taped with PVC tape.

I was thinking of insulating the cold water pipe in a similar manner just for noise control.

In Energy efficiency and durability | Asked By john walls | Mar 30 12
3 Answers

Drywall clips

Regarding a new 1 1/2 story home in a hot humid climate (2B), 2-stud corners at outside walls, spray polyurethane foam insulation, non-vented attic:
I need to use drywall clips for the corners and some other places.


1) There appears to be 2 basic clip types. One screws to the framing, and the drywall just slips into a U shaped clip. The other requires a screw in both framing and drywall. The first seems like it would be simpler to use. Any advice on the best type to use.

2) Any particular manufacturers that stand out for quality/ease of use/or whatever?

In GBA Pro help | Asked By john walls | Mar 25 12
4 Answers

Existing Swimming Pool

Hello All,

I realize that swimming pools aren't necessarily green but I have some potential clients that just moved into a home and they would like to find the most "green" way to heat their existing swimming pool. Can someone point me in some possible direction that might be worth looking at?

They have good solar exposure and they live in an area about an hour north of San Francisco that has hot summers and pretty mild winters.



In Mechanicals | Asked By Daniel Weaver | Mar 30 12
6 Answers

Cathedral ceiling reinsulation

I am in zone 8. One cathedral ceiling I have to rebuild consists of 2"x6" rafters with 2 layers of 1.5" of white expanded polystyrene sandwiching a layer of aluminum foil paper attached to the underside ,or interior side.Old pest damaged fiberglass insulation is between the rafters. Plywood and shingle is on the exterior of the rafters. There is no other structure to the interior of the rafters other than the polystyrene.
The plan is to remove the shingles, plywood,old fiberglass insulation and reinsulate.

In Green building techniques | Asked By Brian de Gruchy | Mar 26 12
1 Answer

What kind of flashing should be provided under trim at interior and exterior building corners?

I have been investigating details for flashing at exterior and interior corners for wood frame residential buildings with vinyl siding and pvc trim boards. I found an article, “Details that Keep Walls Watertight” which recommends a double layer of house wrap at the corners. CertainTeed’s vinyl installation manual recommends a 20 inch wide aluminum coil be run up the full length of the corners, for both vinyl and pvc trim. Do you think that is necessary or desirable? Thanks for your help!

In Energy efficiency and durability | Asked By josef chalat | Mar 30 12
9 Answers

Improving attic insulation in 1.5 story Cape


I just bought a Cape in zone 5A in NH which has two rooms upstairs, splitting the attic into three zones. The side attics, and the space above the rooms. The space above the rooms is vented with gable vents on the ends and a continuous ridge vent. The side attics are my concern. One side appears to be completely sealed, and has 'balsam wool' insulation in the rafters, completely filling the rafter depth. It seems to be in decent shape but there are some holes and insulation falling out here and there. Under the floor boards there are some batts but the coverage isn't perfect.

In Energy efficiency and durability | Asked By Dustin Hotaling | Mar 29 12
5 Answers

What are the pros and cons of using PVC trim on the entire house as opposed to a quality wood product?

What are the pros and cons of using PVC trim on the entire house as opposed to a quality wood product? If wood, what species?
I'm not sure of what type to use. Hearing different opinions in regards to movement and times of seasons to install due to movement etc....

In General questions | Asked By Timothy Hickey | Mar 17 12
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