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2 Answers

Condensation on soffits after painting

I have a split-level house that has an second-floor overhang with soffits where the a/c ducts terminate to supply the 2nd floor with a/c and heat. We repainted the exterior of the house a week ago and now exterior condensation is forming on the soffits directly below the a/c vents. I've lived in the house for 10 years and we never had any issue like this that I'm aware of. This condensation keeps the paint from drying/curing. What should I do?

In GBA Pro help | Asked By Buzz Mershon | Aug 27 16
9 Answers

Insulating a finished garage with unvented cathedral ceiling

Hello -

I am hoping for any input/advice about insulating my garage, which I'm in the process of finishing. The details are:

This is a 20 x 20 garage, uninsulated concrete slab floor with an epoxy finish on it. Unvented roof which will have drywall up to the peak. The walls are ordinary 2x4, the ceiling is 2x6. The garage has several windows, all double-page argon/low-E and a insulated garage door that seals surprisingly well (but it's still a garage door).

This is in Denver, CO zone 5.

In Energy efficiency and durability | Asked By Dave H | Aug 9 16
6 Answers

Following up on the musty smell in our crawl space

Editor's note: This is a follow-up to a previous thread on GBA. The previous thread was Why do I have a musty mildew type smell in my conditioned crawl space?

In General questions | Asked By Linda Larochelle | Aug 26 16
3 Answers

Questions about minisplits and Manual J

Is it possible for someone to provide me with a a manual J online without visiting my home? I cannot find anyone in my area who I feel is qualified.

I can provide whatever info is needed. I've drawn details sketches of all measurements of my home. I've had a blower door test. I know the insulation levels.

We are planning on making improvements over time, however. But I'm interested in a current calculation based on what I have right now. And then as I make improvements I can see how it will adjust the load requirement.

In General questions | Asked By Ryan O'Rourke | Aug 27 16
2 Answers

Gluing polyiso to metal and plywood

Hey everyone -

I'm planning to convert the floor of a van, adding polyiso insulation and plywood

My question is about the best product(s) to use - I'd rather not screw the plywood into the van floor so glue will have to provide all the needed support (and survive through all of the vibrations and bumps)

First layer: 1/2" polyiso, glued to the van floor (metal)
Second layer: 1" polyiso glued to the bottom polyiso layer
Third layer: 1/2" plywood glued to the second polyiso layer

So far considering 3M 90, The Great Stuff, and / or the Loctite PL300 Foam Board Adhesive

In General questions | Asked By Brian Keefe | Aug 26 16
73 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.

In General questions | Asked By John Sexton | Aug 7 16
5 Answers

Cellulose over 1/2" drywall and 24" o.c. furring strips


In Energy efficiency and durability | Asked By Marc Delisle | Aug 26 16
7 Answers

Is there a way to seal VOCs?

We had our front stained. The company used DuraSeal stain. I know it isn't the most ecofriendly, but since it was exterior door we agreed because they said it was very durable. Well, they spilled the stain all over the subfloor and brand new drywall on the interior of the house. I am freaking out a little bit since we have a chemically sensitive child. We are installing hardwood floors (which will not create an air seal). I plan to have them pay to replace the drywall that is soiled. However, I don't know what to do about the subfloor. Is there a way to seal in the chemicals and VOCs?

In Green products and materials | Asked By Carolyn Farrow | Aug 25 16
10 Answers

What to do about stairs and doors during basement energy retrofit?

Good evening,

In General questions | Asked By adam stanton | Aug 24 16
5 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.

In General questions | Asked By Clay Whitenack | Aug 25 16
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