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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
7 Answers

Pier foundation - how much space would the plumber, HVAC people prefer?

We will be building a house for my brother in Upstate SC next year. We are currently in the design phase and having a disagreement on where to put the downstairs kitchen and bathroom with the plumbing lines.

I am thinking along the lines of what makes the house the most resilient and easiest to repair and who knows what he is thinking. The house will be on a pier foundation because it is near a flood zone. The land is sloped so that the piers at the driveway side will allow a crawl space of 3 feet or so and probably 6 feet at the other end near the pond and the flood zone.

In General questions | Asked By Lucy Foxworth | Mar 26 12
5 Answers

Website improvements

GBA is working on some website improvements, and we're encountering a few glitches on the way to a better future.

Today's problem includes the occasional blank line that appears (unwanted) in the middle of a sentence, usually after a glossary term. We're working on fixing the glitch.

Please bear with us as our team works on solving this software code problem. And if you want to draw our attention to any other irritating glitches, please do -- by posting a comment here, or by e-mailing me:
martin [at] greenbuildingadvisor [dot] com


In General questions | Asked By Martin Holladay | Mar 6 12
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