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7 Answers

Nits & grits redux

SPECIFICATIONS:
Climate zone 3A (Atlanta, GA)
3 levels with basement walk-out to rear
Bonfiglioli wall
2x6 studs
Batt insulation in 7.25" cavities, type TBD
Plywood sheathing
Seams taped, type TBD
Housewrap lapped, type TBD
No exterior insulation
Air gap to majority brick exterior wall veneer
Rainscreen to minority fiber cement siding
***VENTED UNCONDITIONED ATTIC***
Fluffy insulation above upper ceiling, type TBD
Site-built roof frame, 5:12 hipped upper roof with some 3:12 lower level roofs
Plywood sheathing roof deck ***NO INSULATION***
Peel & stick lapped, type TBD

In Energy efficiency and durability | Asked By PJ Clem | Jun 8 18
9 Answers

2x6 stem wall detail options

Hello everyone,

I'm in the early stages of designing my future home and ran into a situation where I'm looking for some input. I'm wondering what the best option for me would be at the intersection of the radiant floor slab, foundation stem wall and 2x6 exterior wall. I've attached the 3 options I'm considering.

In Plans Review | Asked By Sturg | Jun 7 18
7 Answers

Rain Screen: Horizontal furring strips with corrugated metal siding installed vertically

I am installing corrugated metal siding vertically over 1" Roxul Comfort Board exterior insulation, thereby necessitating a horizontal furring strip that can bear the weight of the siding. We originally furred the windows out by 2 3/4" with the idea that we would use 1 x something vertical furring strips to allow drainage, then 1 x something horizontal furring strips for the metal.

In General questions | Asked By Amy Hazeldine | May 28 14
5 Answers

Flat roof attic venting

My first question is.... can anyone recommend a home energy expert local to me in San Francisco Bay Area (zone 3c)?

My 1100 sqft flat roof has both roof joists and ceiling joists with blown-in cellulose filling the ceiling joist cavity, and about 15" of space between joists. I have 2 soffits (about 6x12" each) on one side of the house, one skylight is permanently vented and overlaps with attic space, and there is a louvre vent in an interior closet (which doubles as access hatch).

In General questions | Asked By DAVID BIANCO | Jun 7 18
1 Answer

Crawl space remediation

Young, dumb and broke, we built the original part of our house (CZ6) on pressure treated piers over bare ground 35 years ago. The floor was insulated with R-19 fiberglass covered with OSB. A few years later we replaced the piers with a shallow concrete block perimeter wall. The exterior from footing to house sidewall was covered with an inch of poly iso protected by a layer of pressure treated plywood.

In General questions | Asked By Ron Rosen | Jun 7 18
17 Answers

Rigid foam for hot roof

I am interested in converting our bungalow attic to finished space, and it was not designed for venting. I've heard I can do a hot roof insulation method using spray foam. However, I am a DIY guy by nature, and was interested in methods I've seen using closed-cell polyiso rigid foam and spray foam cans to achieve the same result, at least in walls. I am curious about using this method on a hot roof. Surely it would cause head-scratching with code officers. Would it work, though?

In Energy efficiency and durability | Asked By Asa Bradford | Jul 13 14
13 Answers

Using one minisplit head (wall unit) for two small rooms

Currently I have a ducted HVAC in my urban rowhouse condo (495 sq. ft total, living room is about 220 and bedroom 180), I have long wanted to install ductless A/C & heat to remove the large duct hanging from my living room and kitchen ceiling and give me an extra closet (worth about $100-$150 month to me). That old system finally died.

Installing ductless in the bedroom is not as easy as I thought - there is limited space above the ceiling &it's a historic facade; condensate will have to go through the entire wall of my apartment to the back.

In GBA Pro help | Asked By haiku_r | Jun 6 18
33 Answers

Heat runs to unfinished basement? Pacific NW area

I realize the basement is considered part of the conditioned space, but I was a little startled at an HVAC guy proposing to cut heat runs into the basement (which we do not plan ever to finish). It's a 1901 basement with concrete walls to ground height and wood joists above that. Previous owners had put fiberglass insulation in the joists, which was a really bad idea as one can see from old water stains. That's long gone, but when we first lived in the house we used to get water coming up through the floor drain during storms (no leaks through the walls that I am aware of).

In Energy efficiency and durability | Asked By Irene3 | Apr 20 18
2 Answers

Sump pump or no sump pump?

We are just breaking ground on our “final” home in Asheville, NC. We had spec’d out a sump pump in our bid, but our builder is saying he almost never installs them and doesn’t feel we need one. We’ve had sump pumps in all of our 7 previous house basements – so we’re a bit nervous about not having a sump pump. Some of those previous sump pumps would run every time there was a hard rain, some almost never ran (primarily when the house had an exposed basement).

In General questions | Asked By Nancy Broadbear | Jun 7 18
2 Answers

Looking for storm window recommendations

Our old farmhouse had the sash in the original double hung windows replaced about 15 or more years ago. Some of the windows also have old cheap aluminum framed storm windows. We are considering putting new storm windows on all the double hung windows in the house and I have more questions the more I look. For example, Larson makes a couple of lines of aluminum framed storm windows that look better than what are on our house now. They are also promoting the use of low-e glass in the storm windows. Is it worth getting low-e glass in this kind of window?

In Energy efficiency and durability | Asked By Jim Erdman | Jun 6 18
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