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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

Asked By Brian Keefe | Aug 26 16
2 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.

Asked By Ryan O'Rourke | Aug 27 16
1 Answer

“Smooth” flex duct

I understand that flex duct is bad in most situations--it decreases blower efficiency and just generally impedes air flow. That said, for a longish (25ft) run of 6" duct, I wonder if it wouldn't be okay to use one of the 'smooth wall' plastic ducts on the market (see http://www.flexaust.com/product/grass-collection-vacuum-hose/) for a good example of what I'm looking at. This would be in a relatively low-pressure type of situation (Minotair hybrid HVAC system installation).

Asked By Jonathan Nagar | Aug 26 16
4 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?

Asked By Linda Larochelle | Aug 26 16
2 Answers

Options to make space for exterior insulation

This is my first post so thanks in advance for any input. I’m finalizing the plans for our new home with in Kentucky, and I’m talking through the option of adding 2” of Roxul Comfortboard on the outside of ZIP wall sheathing with the builder. He has never done this before, and one of the objections he is raising is that it would require making the foundation/basement walls 2” thicker to make room for this since we are already planning on a brick cladding.

Asked By Brad White | 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.

Asked By John Sexton | Aug 7 16
5 Answers

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

Hi,

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?

Asked By Carolyn Farrow | Aug 25 16
10 Answers

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

Good evening,

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.

Asked By Clay Whitenack | Aug 25 16
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