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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
8 Answers

Which surface is most effective for low-e coating in 2-ply laminated glass?

Which surface is most effective for low-e coating in 2-ply laminated glass. I am using it in Thailand (sunny and hot). Some says that I should use on surface 4 because low-e can not work if it does not contact to the air. But there are some cases that use on surface 2. Which surface is better?. I also would like to know how the kinds of coating (soft coat and hard coat) affect in this case?

In Green building techniques | Asked By Puri Tammarongtam | Mar 26 12
1 Answer

Covering Paint with Non-VOC Paint?

My painter used regular paint instead of the no-voc product we picked. Is it worth having him cover it with the no-voc paint? Or is it better to just leave it as is. Given that "no-voc" paint probably still has some VOCs, we don't want to add more VOCs unless it would provide some type of sealing benefit over the VOC paint. thanks

In General questions | Asked By Brian Jackson | Mar 28 12
1 Answer

Redwood siding corrodes building paper?

I recently moved into a redwood-sided house built ca. 1992 in climate area 5A (midwest). I have have problems with leaking roofs - i thought - until the roofer took off some of the siding below an area where two parts of the house come together - to find that the building paper was corroded, the sheathing completely rotten, and studs and sill plate partially rotten too.

In GBA Pro help | Asked By Katie Grigg | Mar 28 12
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