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2 Answers

What coolant that can be applied to an existing metal roof? Cost a fortune to cool building.

Trying to cool my building. 15 yr old metal building for retail business.

In Energy efficiency and durability | Asked By amelia quinney | Feb 7 16
9 Answers

Plywood as exterior cladding

We are in the master planning phase of building a modern house in the PNW. We are in the Marine zone 4c. We would like a clean exterior that fades into the landscape and do not want a house that looks like it doesn't belong on the land. Considering this, I have a question.

Why isn't stained plywood used as exterior cladding? Will it work if we have good roof overhangs and a 1" ventilated rain screen? We are researching this as we would like an organic looking exterior that is clean. It seems like this practice is prevalent in Australia and NZ but not here in the US.

In General questions | Asked By Jay Raja | Feb 6 16
1 Answer

Are back flow dampers needed for intake on ERV?

I am installing a couple of the panasonic spot ERV's. One of them will use two matching wall exhaust hoods with the the flapper removed on one for the intake. Should I install a back flow damper just inside of this? Or would this be pointless because any breeze blowing in the duct would be strong enough to open it?

On the second ERV I am installing one of Panasonic's "Y" combiners that combine both 4" ducts to one 5"duct and intake/exhaust hood. This is what it looks like.

In Mechanicals | Asked By Kail Zuschlag | Feb 5 16
1 Answer

Bathroom ceiling

I am going to be installing t&g pine (sealed all 4 sides and ends) on a bathroom ceiling. The ceiling is below an unvented roof and conditioned attic space (8" closed cell foam in rafter bays). Climate zone 8.

I want to know if I should install the t&g directly to the framing members or to put up drywall first. I already have an ignition barrier over the foam. Will drywall just be a surface for mold and mildew? I have a Panasonic whisper green vent fan and a window in this 72sq ft bathroom.

Thanks

In GBA Pro help | Asked By Jon Patrick | Feb 6 16
1 Answer

How to fix shoddy garage addition?

This past summer I bought a house in SE Michigan (Zone 5a) that was built in 1978; we had an energy audit done and the auditor alerted me to a host of issues included that when they built out into the garage to expand the kitchen & laundry room they left the top of the walls and ceiling open to the unheated garage.

My question is what is the best way to go about fixing this issue from a cost standpoint. I'm concerned if I just seal the top off the wall with XPS & Great Stuff that condensation will collect since there will be colder air inside the wall from the uninstalled garage.

In General questions | Asked By Patrick B | Feb 6 16
2 Answers

Fireplace insert or glass doors + outside air intake?

I have a rather large fireplace that can clear the house of all heat, so I am never really using it. Would be nice to make it functional source of heat and have it as a backup for those times in winter we lose power or when minisplits can't cover entire heating load.

Question: do I have to go the expensive fireplace insert + outside air supply route, or going with the proper glass doors + outside air supply would give me good return on investment?

In Energy efficiency and durability | Asked By Apollo S | Feb 6 16
1 Answer

Concrete sealer needed before finishing basement?

I live in a home in Zone 5a that was built in 1978 with a poured concrete basement, our house sits relatively high with ground sloping away from the foundation. We are planning on finishing out basement it with XPS and then metal framing/drywall.

In General questions | Asked By Patrick B | Feb 6 16
1 Answer

Does plywood flooring have to be removed before adding insulation?

My attic currently has a settled 8" of blow in insulation. I am adding more batts at an R-30 value. Previous owners installed plywood on joists for storage and nailed it every 6". Can the batts I'm addind be placed over plywood or must it be removed?

In General questions | Asked By Dan Dadario | Feb 6 16
25 Answers

Final advice on insulating a basement correctly

Hi I’ve read the great articles here on how to insulate the basement correctly - I just want to make sure I'm going to do the work right and I trust the folks at GBA

Overview

• Southern exposure home – south has 2x6 pt walls with a few windows and doors (basement level)
• North has an 8ft concrete wall that behaves like a huge cooler – it also has a 24inch 2x6 pt wall on top of that, so the basement ceiling height is 10ft.
• In the worst heat in summer 90 degrees + the basement is extremely cool with the windows closed – just like air conditioning

In GBA Pro help | Asked By Robert Metelsky | Aug 4 15
9 Answers

Roxul comfort board in basement?

I spoke to someone at the Roxul company the other day who recommended the following basement insulation. First, tyvek or similar against the concrete basement wall, then 1 1/4 " roxul comfort board for a thermal break, then a stud wall filled with roxul batts--- sheetrock. Do you see a real problem with water condensing on the concrete with the comfort board and tyvek there? Still seems like too much work but I am curious performance wise.

In Energy efficiency and durability | Asked By Nyle Phillips | Sep 27 12
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