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3 Answers

We live in Massachusetts and recently replaced our roof with Ecostar plastic shingles and the rep forced the roofer to expand our soffit vents and ridge vents as part of the installation. We had a much delayed energy audit in the midst of the installation and the recommendations have put us in the middle of what seems to be an experts' dispute. The energy consultant says seal the soffits, spray foam and dense pack the closed rafter area leading from the second floor knee wall to the attic flat.

In Green building techniques | Asked By Stuart Warner | Nov 16 11
6 Answers

I've been chasing a low-cost flow hood for monitoring performance of my ventilation system for some time now, hoping to get one used, or through my HERS rater, and recently discovered a comment made by Martin here on June 15th '09 referring to a way of making a homemade flow hood "from a cardboard box and a $90 digital anemometer". (Right under my nose)

Can you give us an updated design for such an elegant contraption and recommendations for what anemometer to buy and what other diagnostic tests we might be able to accomplish with it? the choices on these things is overwhelming.

In Mechanicals | Asked By Michael Chandler | Nov 15 11
49 Answers

I thought I recently read an article on the Building Science website talking about problems installing batt insulation over spray foam - moving the dewpoint to the spray foam layer and causing the batt to get moist where it meets the foam. Now I can't find it anywhere and am wondering if I understood it correctly.
Can anyone explain this to me better or point me to more information. Thank you so much.

In GBA Pro help | Asked By Amanda Evans | Jun 23 09
5 Answers

My home is a 1985 passive solar timber frame with wrap and strap construction located in southeastern MA. The roof deck is 1x6 TandG followed by a plastic sheet ->3in polyiso ->1in polyiso ->plywood-> shingles(no paper). The shingles are ready for replacement and there is known rot at the sheathing around the vent stack which was never sealed(spray Foamed). In replacing some siding (2in polyiso w/vented rain space and clapboard) I noticed that there is no tape or other air sealing.

In Green building techniques | Asked By T White | Nov 10 11
5 Answers

My main roof is hipped, with cornice all sides. Can i use the iso board with paper face to insulate the rafter bays from inside?

I would lay it against the sheeting, leaving 1'' of air space, and seal with 2" of foil faced foam board sealed with foil tape. Strap with 1x and finish with 5/8 drywall, creating habitable space. Roof has new light colored dimensional shingle.

In Energy efficiency and durability | Asked By richard miller | Nov 15 11
3 Answers

I am investigating/interviewing contractors to build our new construction in central North Carolina, near Winston-Salem, where temperatures and conditions are milder than in the mountains. We are considering a hybrid timber frame with exterior SIP walls and roofing SIPs. Simply put, what would you recommend as the construction sequence and materials for the walls? We've been told that an R-22 wall system would be sufficient with a strong focus on preventing air leakage.

In Energy efficiency and durability | Asked By Tom Gagnier | Nov 15 11
7 Answers

Good evening,

My wife and I are building a new home in Wyoming. It is something we have always wanted to do and we are trying to be as green as possible within our budget. It is about as close as we could get to being a passive house, but we do have an in floor heat system on the first floor with exposed slab covering an open living room and kitchen. This is where my question begins...

In Energy efficiency and durability | Asked By Paul Treide | Nov 13 11
4 Answers

Hi all,

A friend has left over rigid backed foam insulation and asked me my thoughts on using it to completely fill the rafter space (no air space) for a portion of a roof on small houseboat. He want to use two layers of the foam (both foil backed). Orientation of foil? Bad idea altogether?



In Green building techniques | Asked By Daniel Weaver | Nov 15 11
1 Answer

I've read several postings in your blog on the subject of roof venting and cathedraled ceilings but haven't found an answer yet for my project. It's a half story room above a garage that is completely unfinished on the second story. It has 5' tall walls on the eave sides, built on top of a wooden I-joist floor system which is insulated with R-38 fiberglass. The roof is a 10/12 pitch, gable end on one side and attached to the existing house on the other.

In General questions | Asked By Marc Beatty | Nov 15 11
1 Answer

Can anyone recommend an affordable device to record temperatures?
Want more than just the daily high and low, maybe once per hour.
I have built several passive solar homes, some with high thermal mass
and some with no additional mass. Would like to monitor temerature swings.


In General questions | Asked By Richard Patterman | Nov 15 11
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