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5 Answers

Exterior Roxul batt insulation in semi-conditioned space?

I'm building a 10x14 timber frame shed in upstate NY climate zone 5. It's under 144 sq.ft. so doesn't require building permits or inspection. I have pine 2x T&G roofing and 1x wall cladding from a local mill. The building will be used occasionally as a workshop, including during winter. For this reason I'd like to insulate it. I'm grumpy about foam for various reasons including rampant carpenter ants around my property and so would like to use rock wool.

Asked By Michael | Nov 23 15
17 Answers

It seems the trap was left out on the shower drain on a slab house. Any way to fix that short of a jack hammer?

My son just moved into a slab house on a septic system. After using the washing machine, they noticed a sewer smell coming from the shower drain. They had showered the day before. If there is indeed no trap between the shower and the septic tank, is there a solution short of a jack hammer? Perhaps a valve? The drain is a trough style with a 1.5 inch opening.

I told him that maybe the washing machine had emptied the trap. There is a vent for the washing machine and behind the shower.

Is there a simple way to tell if there is a trap? Thanks

Asked By Tooger Smith | Nov 10 15
10 Answers

Closed-cell spray foam between studs with various exterior continuous insulations

I want to make a few questions very explicit to get some good solid answers.

Asked By Patrick | Nov 19 15
3 Answers

Installing rigid foam insulating board on the interior of an exterior wall

1890 house we've pulled the plaster and lathes off. Have access to exposed exterior wall between studs from the inside. Can we cut and tightly fit 2" board between the studs, Should it be snug to the exterior wall? Or will there be a moisture do we prevent moisture issues? If we double layer the board does it increase effintiency? do we need to tape the seams against the studs? We live in Maine.

Asked By Andrea | Nov 23 15
1 Answer

New HVAC problems

I recently had my hvac system and all flex duct replaced due to age of unit and mold throughout. I live in a Florida 1930's home and the ducts are in the crawl space under the house, also we have had a problem with critters making holes in the ducts.

Asked By Deidre Epperson | Nov 17 15
3 Answers

Downloading Details

Details will not open in Autocad LT 16
Any Advice?

Asked By Carole Coelho | Nov 18 15
9 Answers

How to excavate trench in gravel when foam is above?

New slab on grade in Zone 4A:

I plan to have about 8” of compacted 1/2” crushed stone (no fines) with 2” of XPS sheet foam, then poly of course, then 4” slab. I will need to have two trenches of a thickened-slab type footer for bearing walls.

Asked By David McNeely | Nov 16 15
19 Answers

Accidental deep energy retrofit


I'm doing a gut renovation of a stucco-sided house in the high desert. We changed most of the window sizes to improve the passive solar performance of the house, which means a lot of stucco repairs. Now my contractor is telling me we should remove all the stucco and start from scratch, rather than trying to tie new tar paper to old tar paper at the studs. It'll cost a little more, but we'll get a better result.

Asked By Reanna Alder | Nov 5 15
17 Answers

Proper metal roof installation.

We are building a new home in Southeastern Pennsylvania. We are having a Drexel Metal standing seam metal roof installed over plywood sheathing. The attic is unconditioned space with blown in insulation to a value of R-60 or so. Should the metal roofing be installed over strapping. We will have a vented soffit for air circulation.
when discussing with the roofing contractor he is adamant that this is not necessary or appropriate. My thought is that the metal should be separated from the plywood.

Asked By william dempsey | Nov 10 15
4 Answers

Retrofit unvented catherdral ceiling

Hello and thanks in advance for help ...

I am in zone 5 (by your map) Ohio and have a typical cathedral ceiling room addition from the late 70s. T&G knotty pine, followed by 6" fiberglass in 2 x 6 rafters and then the roof plywood ...of course now rotten and was previously replaced!. I am a senior lady trying to get the contractor to do it as correct as possible this time. None of the carpenters seem to know what to do with my situation so I have had to do the research.

Asked By Arlene | Nov 13 15
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