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80 Answers

Two condensation questions

I have a newly foamed attic with open-cell foam (average 8 inches or so with rafters covered) and a brand new AC unit with furnace. I had thought that lowering the temperature of the attic would take away the need for insulation on the condensate drain line, but it is still sweating. The upstairs temperature is in the 75 degree range in the Attic is in the 81 degree range, but the Attic humidity has gone from being in the thirties or forties when it was a vented attic to being about 70% now, so I guess the dew point is still high enough to necessitate insulating the drain line.

Asked By John Sexton | Aug 7 16
18 Answers

Log wall spray foam insulation: closed or open cell?

Hi - Man, I'm glad I found your site because I'm torn and need advice for this unusual situation.

Asked By Dave Beller | Aug 30 16
0 Answers

Through-Fastened Metal Roof Issue / Standing Seam Option


In this post:


and in this:


you talk about the merits of through-fastened metal roofing. I agree on most aspects.

Asked By Pat Kiernan | Aug 31 16
7 Answers

Water between the bottom of the window and rough opening?

Building a home in zone 4A and we done with framing and setting the windows and house wrap. The windows have been flashed and the house wrap is taped to the window on all 4 sides.

This morning, the builder needed to take a window out, and when he did he noticed a lot of water under the window between the window and the rough opening. He said it was a lot of water.

Asked By Clay Whitenack | Aug 25 16
5 Answers

Can bees damage a structure if they get behind the siding?

If bees/wasps/ect get behind the siding of the house such as in a rain screen detail, can they cause structural damage?
If just a straight fiberglass insect screen is installed against the wall sheathing and folded up over the furing strips, is this sufficient or should it be wrapped over something solid like the cor a vent product? I know it used to be detailed this way before products like cor a vent, but were there legitimate issues with bees/wasps?

Asked By eric Mikkelsen | Aug 31 16
13 Answers

What would you do?

Forgive me for the vague title and the long post but I am lost in possibilities... all expensive!

Oh and its complicated because I am forced into a decision NOW that will heat my 850 sq ft house AND be adequate to heat in a year (or two) when I add 1000 sq ft. The math gets fuzzier when I tell you the plan is to add 4 inches of EPS to ALL the exterior walls (including existing) and 6 inches under the NEW basement concrete).

No one here (Canukistan) is able or willing to do a manual J to size a unit for a two fold job...

I live in Kenora Ontario Canada (zone 7);

Asked By tim brown | Aug 17 16
31 Answers

While I love radiators, I hate using fossil fuels

I live in an 1890 Victorian in Southern Pennsylvania, heated by oil. While I love radiators, I hate using fossil fuels! Is there a way to use green technology to use less oil? My methods to date have been uncomfortable - installing a wood stove.

Is there a way of boosting the boiler with green energy? Would geothermal help? I'm newly divorced and ignorant about systems!
Thanks, Susan

Asked By Susan Hanway | Aug 28 16
1 Answer

How many minisplits for an old house?

I have a three story brick duplex built in 1925. There is currently no ductwork (steam heat) and I doubt that it's feasible to install. Windows are wooden double hung with storm glass, they are in fantastic shape and I'm not particularly interested in replacing them.

Unfinished basement, 1st and 2nd floors are all 1380 sq ft, but I'm not concerned about conditioning the basement. 1st and 2nd floors have 3 bedrooms, living room open to dining room standard doorway to kitchen. 3rd floor is 690 sq ft split into 2 rooms.

Asked By Aaron McMillin | Aug 31 16
13 Answers

Best HVAC system and suggested improvements

My wife and I are seriously considering building a home on a large lot in a rural area near Rochester, NY (Zone 5). Our general plan is a single story house slab-on-grade house with a partially enclosed courtyard. It poses some challenges, because for its floor area, it has a large and long footprint. I've attached my rough plan for the house, with the hope that I can get some good insight from the GBA crowd.

Asked By John Ranson | Aug 30 16
1 Answer

How do I insulate the attic stairs to R-38?

According to 2015 IRC Section N1102.2.4:
“Access doors from conditioned spaces to unconditioned spaces such as attics and crawl spaces shall be weatherstripped and insulated to a level equivalent to the insulation on the surrounding surfaces.”

Asked By Dylan Hillman | Aug 31 16
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