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2 Answers

Foam Insulation on attic floor?

I'm about to insulate my attic. I've read a lot about insulating the attic rafters with foam to create an unvented attic. I've read about laying down a think layer of loose fill on the attic floor in a vented attic. I'm having difficulty deciding between them. And now am wondering about a third option.

Asked By Jason Crawford | May 3 15
4 Answers

Design Temperature

Design Temperature

It seems like most systems are designed around maintaining comfort on the coldest day of year. This can mean that the heating system is specified for 60,000 BTU but your average BTU requirement is 12,000 BTU. The mismatch likely adds quite a bit to the price tag of the boiler or possibly necessitates a boiler instead of something more economical?

Why wouldn’t a secondary heating system that can add heat to cope with the few days of the year where the heat requirements are at their highest be a more economical design?

Asked By M G | Apr 29 15
4 Answers

Need help puzzling through the details of outfitting my house with a mini-split system

Right now my house has a 19 year old 125,000 BTU 80% efficiency gas furnace with ducts in the unconditioned attic, partially buried under insulation. I'd like some help determining if mini-split heat pumps will work as replacements, and in what configuration.

Asked By Nathaniel G | May 2 15
2 Answers

Skip the plywood, go right ot the Comfortboard IS

I live in central Vermont, heating zone 6, hoping to get a little bit of feedback on the wall system I have in mind for a 4 season workshop (barn), with small efficiency apartment on the second floor.

Asked By Blake Olson | May 2 15
14 Answers

Need condensation control — Want a bath vent without another 4" hole outside

Any brainstorming helps.
Have "sealed" window in bath anyway but do not want to open in winter north Iowa.
Radon vent (other side house) condensates.
So I don't want to make another 4" hole for bath vent.
When I turn on radon fan I hear water slosh down in pipe that's horizontal.
And dryer is another 3" hole. That condensates too. (I tried manual fix. See pics.)
And vent stack is another 4" hole.
And gas water heater is another 3" hole out chimney.
And water pipe is another.

Asked By Charlie Darwin | Apr 30 15
0 Answers

How can I seal this space w/ moisture in mind?

Hi All,

I am working on renovating our second floor which includes putting in a master bathroom and gutting and redoing an existing 2nd floor bath. It is a 1952 cape with brick siding on concrete block. The masonry walls are completely uninsulated in most cases. I have taken advice from the GBA site while researching various issues associated with this project and figured this would be a good place to ask about this.

Asked By G S | May 2 15
13 Answers

Repairing notched bottom plate and floor joist

I am moving a cold air return before I insulate my home and as the title suggests, I'm looking for some advice "repairing" some of the notches.

Asked By Nathan Schulte | Apr 29 15
1 Answer

Small spots on inside of Weathershield double pane windows with argon gas

I purchased and installed vinyl clad Weathershield windows. They are showing spots on the inside of the window panes. Has this window failed or is this the result of the argon gas failing. I notice them at the bottom few inches. I am attempting to sell my home and buyers are concerned at what might be going on. They will rely on your opinion.

thank you, Gene.

Asked By Gene Schiferl | May 1 15
2 Answers

Did I build my roof incorrectly?

I am the Owner/ GC for my house. I also live outside of Austin, Texas. I directed my roofer to overlay the outside OSB decking, with StormShield, an adhesive water barrier, instead of felt. On the inside of the roof, I had Open-Cell foam sprayed 6 inches thick, and sealed the inside of the attic space.
When you look at my house from the outside, it's possible to see the 'outline' of the attic area. It's as if there is a visible temperature variation apparent, from the insulated portion of the house, than from areas where the spray foam is absent (like the garage).

Asked By STEPHEN VENSKI | Apr 30 15
3 Answers

Sealing around fire sprinklers in cathedral ceiling

I have a vaulted, insulated, cathedral ceiling in warm California (zone 3) and code required firesprinklers for my tiny guest house (5 total). My piping and sprinkler heads are installed in the center of my 2x12 bays, which will be filled with R-38 fiberglass batts. I have another R-18 of rigid insulation above the roof sheathing. Once insulation is in place, I will install drywall. The firesprinklers have covers for them (similar to photo) with fusible links that will open in extreme temperatures.

Asked By Dan Burgoyne | Apr 29 15
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