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12 Answers

I will be having my attic sealed and insulated with closed-cell spray foam. However, the design of my house makes this a bit more complicated because my roof cuts into the second-story ceilings at the front and rear edges of the house (will make more sense if you look at the attached pic).

Above this part of the ceiling, there is only some very old batt insulation (less than R-8) and the roof deck. The house doesn't have eaves/soffits, so there is no venting in this area.

In Energy efficiency and durability | Asked By Matt Culik | Aug 14 14
5 Answers

For a large scissor truss (top chord 31" above bottom chord), we want around R-70 but no more. How do you 'contain' the blown in, or how would you use batts?


In GBA Pro help | Asked By David A Flannery | Aug 18 14
8 Answers

I want to install a secondary heating system (wood stove primary). Cold climate. What is best ductless heat pump for an open house plan, 2-story?
Are heat pumps better than ETS systems?



In Energy efficiency and durability | Asked By Kelly Mitchell | Aug 16 14
2 Answers

HI all

Thanks to Dana and Martin (and others) for earlier comments and guidance on my new house build. To be filed under the you cant make this $hit up, it burned down right before we moved in (VOC spontaneous combustion - re stain rags on the pine ceiling/walls really can occur).

soooo, we get to take apart what we just built and analyze it. and improve upon it the next time (deconstruction under way now, framing to start about labor day).

In Green products and materials | Asked By pat rowland | Aug 18 14
5 Answers

I was speaking with my passive house consultant the other week, and she expressed concerns about boring critters and subsurface rigid insulation. She had such an experience with some insulation in her garden (It was put in one season and removed at a later time as she got back to completing the project.)
Now, I know all about the ate/termite protection used in these insulation products, but what about larger critters that would love to have a warm dry home?

In General questions | Asked By Steve Young | Aug 16 14
5 Answers

I just stumbled upon a type of clay brick that is apparently gaining popularity in Europe but seems totally unknown here in the USA. Example: http://www.juwoporoton.com/products/

In Energy efficiency and durability | Asked By Nathaniel G | Aug 16 14
5 Answers

We are building a new house with geothermal heat and a lite form basement and lite deck first floor floor. The first floor wall assembly is board and batten cedar siding on Tyvek drainwrap on 7/16 OSB on 2x6 girts at 30" oc with 2x4 vertical framed walls. We have R40 SIPs panels on the roof under a metal roof. We are planning on 2" of closed cell insulation on the walls. I have been reading about including batt insulation as well and was wondering if anyone had a recommendation either way?

We are also including a fresh air exchange in the HVAC system.

In Energy efficiency and durability | Asked By Lori Loehr | Aug 13 14
6 Answers

Here's the scenario:

48' x 104' building in climate zone 5. 48' x 64' of that area will be unheated garage space. I'm still debating the merits of insulating this area. The other park of the building, 40' x 48' will be heated only (no a/c). The area above that is a room in attic area that will be conditioned year round. The room in attic area is 20' x 40', with two 10'x11' spur areas that were allowed by implementing a gable dormer on the main dormer roof line.

My proposed attic ventilation is as follows:

In Energy efficiency and durability | Asked By Rick Van Handel | Aug 11 14
5 Answers

I'm putting recycled 4" XPS under my slab. Zone 6. Do the joints need to be sealed with anything? I'll put poly on top, under the concrete.

In Energy efficiency and durability | Asked By stephen sheehy | Aug 11 14
1 Answer

A few days ago, the friendly folks on this site helped me come up with a basic attic insulation plan for my house. However, there's a potential issue that I could use additional input on.

First, a quick description of the house/project:

- House is in Northern NJ (climate zone 6A)
- Built in the mid-1940s
- Stick construction
- Relatively simple gable roof currently covered with asphalt shingles that will probably need to be replaced in the next five years
- The roof stops at the edge of the house - there are no eaves/soffits, and thus no eave/soffit vents

In Energy efficiency and durability | Asked By Matt Culik | Aug 11 14
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