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24 Answers

Exposed Wigluv tape

The spec sheet for Siga Wigluv tape claims that it is "UV stable". Does
this imply that it's appropriate for little seal-up jobs on the exterior?
There are a couple of funky end-cap joints on my metal roof which could
let water in if windblown rain arrives horizontally, and I'm thinking
a slap of Wigluv over the slots would be an acceptable fix if it's
likely to last more than a couple of years under sun exposure.

Or are any of these products too new to really know? Did any of the
Siga offerings make it into the "backyard tape test"?


In Green products and materials | Asked By Hobbit | May 9 15
3 Answers

Poor man's spray foam help

Newbie here:

I am rehabbing a stickbuilt cottage in FL. It was torn back to studs by the previous owner. I obtained permits and am actively getting through the inspections and such. Next step is insulation. I discussed the process of foaming in cut foamboards and the county seemed ok with it. I bought 1 1/2 inch polyiso board from a recycle group that is in great shape. I have close to 200 4' x 8' boards.

In GBA Pro help | Asked By Ferrell Brown | May 14 15
9 Answers

Window replacement

Hi. I need to replace a 5 1/2 foot x 22 inch window in my kitchen . It is 16 years old, has had foggy streaks in it for over 5 years (gets lots of sunlight) and I am told it can't be repaired.
I called two companies to ask for quotes. They replied with quotes over the phone. There was a price difference of over $100.
Turns out one quoted 3 mm thick glass, one quoted 4 mm. thick glass.
Don't they need to know the thickness of my current glass, and match that?

Is there anything else I should specify in the quote? If so, in your view, is it a 'nice to have' or a 'must have'?

In General questions | Asked By Ann Piece | May 14 15
2 Answers

Foamboard and creep deformation

I have been trying to find a way to insulate a brick ledge on the north side of my home. I am planning a large insulation upgrade to help get my floor heat somewhat working and seal up the house some.

In General questions | Asked By Mike M | May 11 15
3 Answers

Insulating rafter bays with sistered roof rafters

I have a newly constructed home in Massachusetts, built to minimum energy standards (or maybe a little below).

The attic is unfinished, but the builder planned to finish it one day so he insulated the 2x10 rafters with a "flash & batt" approach. There are 4 inches of a sprayed on foam in the rafter bays (I would guess R-24 to R-28) and 3.5 inches of R-15 fiberglass. The fiberglass is held in place with vinyl straps and a layer of Membrain vapor barrier. There are soffit vents and a ridge vent, but these appear to be unused and blocked by the foam, at least in the rafter bays.

In Energy efficiency and durability | Asked By David Lewinnek | May 14 15
1 Answer

Wall system for recording studio / home. Vapor questions?

Hello, thanks in advance for your time and knowledge. This site is a great resource.

I am building a home / recording studio in Murfreesboro, TN (zone 4A) and have some questions about my wall system. My plan is to build my walls in the studio as such: vinyl lap siding, 1" xps foam taped at all seams, osb taped at seams, 2x4 walls with rock wool batts, 5/8 drywall, 1/2" sound stop fiberboard and finally one more layer of 5/8 drywall painted. All air sealed as best I can. My question / concern is about vapor.

Does this wall system pose any issues with vapor?

In General questions | Asked By JOE ROBERTS | May 13 15
6 Answers

Flat roof advice needed

I’m building a carport and breezeway in southeastern Michigan and I’m struggling with construction methodology and products for the proposed flat roof.

Flat roof? I know…Martin's Ten Rules…But… I would like to use all this roof real estate. This roof will cover a substantial portion of my small urban lot and I think, in the future, this could be valuable space. A Small Deck, a Modular Green Roof, Potted Gardens, Solar Panels…

In General questions | Asked By Howard Road | May 11 15
3 Answers

Spraying foam into stud bays without any kind of barrier

One of my clients has a pre-war home, (Civil War, that is), and would like to spray foam into the stud bays, although there is no barrier of any kind. Just old pine siding nailed to the studs.
I told him first that he should re-naill the siding using splitless ring shank nails to secure the siding.
Without any kind of barrier, I envision foam squirting out between the gaps.
Short of removing all the siding, and installing a vapor barrier, I suggested lining the stud bays from the inside using roofing felt stapled to the studs encapsulating the stud bays.
Any better ideas?

In General questions | Asked By roger steinbrink | May 13 15
2 Answers

Moisture protection in the crawl space

Does the moisture protection in the crawl space ever need replacing. The one under my house is 12 years old and I was told that moisture protection covers need replacing at least every seven years. Is this true or is it a ploy for business?

In General questions | Asked By Janet Swope | May 13 15
1 Answer

Are Europly, Appleply or good Baltic Birch plywood available in Vermont?

I am specifying materials for millwork and want to use a good baltic birch plywood so I can expose the edges (rather than edgebanding). What is available and a good/not too pricy choice in Vermont?

In Green products and materials | Asked By Anke Tremback | May 13 15
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