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2 Answers

Moisture & mold


We have a high humidity and moisture in house.

Can gap in caulking causing the shower water to leak into crawl space and cause high humidity in the house.

We recently got a new washer and dryer so suspect that is the cause. But plumbers have ruled out any pipe leaks. We are not able to detect the source of water and everyone says gradual water seeping into crawl space can't cause moisture n mold. It has to be a lot of water. Is that true.

In General questions | Asked By Sim Singh | May 17 15
3 Answers

Do minimum thickness of foam rules still apply for the partition wall between an insulated attached garage and the house?

Climate zone 6 location near Green Bay, wi. Partition wall is advanced frame 2x6 wall construction with planned 2 lb density blown fiberglass. I would like to use 1" foil faced polyiso on the cold side of the wall to limit thermal bridging and also tape the panels for a primary air barrier.

In Energy efficiency and durability | Asked By Rick Van Handel | May 16 15
4 Answers

PV and EMF

I hope the title of this post isn't provocative, but I would like to ask an earnest question about photovoltaics and magnetic fields. The link below connects to a study of electric and magnetic fields near residential and commercial PV arrays.


In Green products and materials | Asked By Jeffrey S | May 15 15
1 Answer

Flashing best practices request

I have a 1965 home in Houston that I am doing a deep renovation on. One of the problem areas in the house is the intersection of the upstairs exterior walls with the downstairs roof. There was a vinyl siding with 1/4" foam sheathing.

Today I removed the vinyl siding and foam sheathing. I did not like the vinyl, did not like it's color, and had leaks where it met the roof.

In General questions | Asked By Brian Greul | May 16 15
10 Answers

Backup heat for mini-splits? Electric cove heaters?

I'm planning a house build and am seriously considering using mini-splits. The house will be in climate zone 7 with a -13F 99% design temperature, so I want to make sure I have a source of backup heat when the mini-splits turn off during really cold nights (-25F happens several nights a year), and also to make sure the bedrooms stay warm enough if the doors are closed.

In Mechanicals | Asked By Nick Hall | May 15 15
5 Answers

Garage mold: cause and design solutions?

I'm in Portland, Oregon, climate zone 4C. Last year we bought an existing house (vintage 1943), with an attached 2-car garage. The garage is unconditioned, uninsulated, and unfinished, with the exception of the wall connecting the garage to the house, which is finished, and presumably insulated. It originally was a 1-car detached garage, but in the late '90s, the previous, long-time owner built a kitchen addition connecting the garage to the house, and also expanded the garage to 2 stalls. The garage roof has ridge venting, as well as a few soffit vents.

In General questions | Asked By Doug Elliott | May 12 15
3 Answers

R-38 ceiling and spray foam

If one sprayed 5" of open cell spray foam on a ceiling area, that would equal to around R-17.5, correct?

Now code requires R-38 minimum for the ceiling in this area. There is no "performance value" of R-38 in 5 inches of open cell spray foam, right?

That would be a marketing line bunch of nonsense as 5" of open cell is R-18 avg. and anyone claiming it is performing like R-38 is lying. How would the code department buy into this nonsense?

In Building Code Questions | Asked By Peter L | May 15 15
5 Answers

How to tie in existing shingled roof when adding exterior foam?

I am adding 4" of rigid foam to my house and am looking for suggestions on how to flash where the adjacent wall ties into existing roof shingles. I am curious if there is a way to put the foam on top of the shingles and then flash. This would, of course, cover the existing step flashing and I am not sure if it is a good idea. My original thought was to remove the shingles close the wall and butt the foam straight to the roof underlayment and redo the connection on the outside of the foam with proper tape, peel and stick, and step flashing. Is there a better way?

In GBA Pro help | Asked By Brian Otten | May 14 15
2 Answers

Basement perimeter wall construction

My basement has a full perimeter sump pump; drainage mat on wall from 1 foot below ground level to loop into the plastic cove that empties to the sump drain below; limestone foundation walls; penetrating sealer on the concrete floor.

I plan on installing light steel perimeter walls where no steel will touch the limestone foundation walls. Closed cell spray foam, treated with a fire barrier, will be installed professionally after plumbing and electrical runs are completed.

In Building Code Questions | Asked By Donna Agah | May 15 15
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
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