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13 Answers

Laminate my 2 x 4‘s with another 2 inches or more insulation?

I have a table saw and can rip all day long, plus I have the time, so I was thinking of upping the exterior insulation thickness.
I am insulating the exterior wall in my laundry room plus the framed area above the finder block wall in the corner of my basement that is above ground.
Between the Roxul and the drywall I am putting into those exterior walls I am planning to use Membrain vapor barrier, with staples and acoustic sealant of course. The laundry room is on a slab in my large 50’s split-level home.

Asked By JakeNY | Feb 16 18
0 Answers

Maximizing Thermal Mass in Passive Solar High Desert Home

Hello -

My partner and I are building a small (600 sq ft) house in climate zone 5B (NM/CO border). When we lived in Colorado, we had friends who built commercial passive solar greenhouses using south-facing glazing and water tanks for thermal mass. Using their formula, we calculated that we would need approximately 1500 gallons of water to meet their design specs for a self regulating high desert (7k ft elevation) house of this size.

Asked By ztrain727 | Feb 19 18
0 Answers

Retrofit existing 2x4 uninsulated stucco wall

I’m looking at a conversion of a free standing garage into conditioned (heated) space. The structure has stucco over tar paper, directly over 2x4 studs, no insulation, no sheathing. The goal is to have a painted drywall interior.

Asked By Phil Boutelle | Feb 19 18
6 Answers

Mitsubishi heat pump defrost mode

I just had a Mitsubishi MXZ-4C36NAHZ with a 24kbtu and 9 kbtu unit installed in my house in Vermont. When the temp drops below freezing, my indoor units blow cold air (as in really cold. Not just a fan circulating air, but COLD). This is a quote from the brochure: "and because the system fan turns on only after the target temperature is reached, it NEVER BLOWS COLD AIR."

1. First if that's true, what's happening?

Asked By Joey | Dec 22 15
6 Answers

Radon system design with drain tile to daylight

We are in the process of remodeling our basement and will be pouring a new concrete slab. The house was built in the 1940’s and sits on very dense clay soil. The old concrete has just been removed and we’ve dug down 4” below the top of the footings so that 2” of stone can be placed followed by 2” of EPS, a poly vapor barrier and new concrete. A one year radon test was completed two weeks ago and the average value was 6.6 pCi/l (test completed with all old concrete in place); we will be installing a radon vent prior to pouring the new slab.

Asked By Andy Freeman | Feb 16 18
6 Answers

Insulating Unfinished Basement Ceiling in Flood Plain

Hello, I tried to find an answer to this but couldn't, apologies if I missed it. Our house in upstate NY was built out of an old carriage house (in the 40s). Our subfloor is thick, wide and uneven barn beams, with gaps varying up to 1/2inch in between them. We have an unfinished, full basement. It would get damp, but we have a humidifier that keeps it at 50 humidity. We also live in a flood plain. The house has gotten water into the first floor during a major flood, but in a 100 year flood scenario it will likely stay in the basement.

Asked By Joseph McGrail | Feb 18 18
13 Answers

Crawlspace Beam Layout

Hi Friends,

Long time reader, first time poster. I'm looking for some feedback on my plans on fixing some floor bounce/sag.

House layout is pretty simple, 62x32 with one corner consisting of a 20x20 slab garage. Floor Joists are 2x10s, spaced 16" on center. They span almost 16'. The house has long been neglected, and the crawl was filled with moisture for years. Poor landscape drainage, washing machine leak, and a dryer vented to the crawlspace led to sagging floor joists and a main beam with rotten ends. Plus plenty of mold.

Asked By alexallo | Feb 16 18
6 Answers

How exterior air seal at chimney to wall interface? Chimney spalling.

Hello,

Using a FLIR One, I've found a major source of air leakage into my house from around the fireplace mantel. Using a homemade blower door and a smoke pen I've discovered that the air is in fact entering from the exterior chimney to sheathing interface. While I've been able to find extensive discussion and documentation on this site how to handle through attic air gaps for a chimney, it's been less clear to me how to handle this detail on the exterior wall to chimney brick intersection.

Asked By Mike McLaine | Feb 18 18
7 Answers

Insulating a raised slab

Alright, so here’s one that I can’t find in the great treasure troves of this site: how to handle insulating my raised slab on our new house. Quick details on the project: climate zone 6, 3500sqft, two story, zip-r external insulation/sheeting (R6), fiberglass batts in 2x6 walls, combination vented roof w/ R60 cellulose and unvented roof with R50 foam, low U 4th surface fiberglass windows, and a combination of slab on grade and vented crawl w/ R48 foam. The concrete will be polished as finish floor in slab areas. Heating is entirely mini-split, no in floor radiant.

Asked By User-6804212 | Feb 17 18
30 Answers

Cold weather performance reports from minisplit owners

This morning I drove to town for a dentist appointment, and the digital outdoor thermometer on my Subaru bottomed out at -28°F as I drove through Lyndonville, Vermont.

During the past week, the thermometer at our house hasn't risen about 0°F, even during the afternoon hours. Of course, all of northern New England and the upper Midwest has been experiencing similar temperatures this past week.

So I'm taking this opportunity to ask owners of minisplits to report on how well their systems are working during the recent cold snap.

Asked By Martin Holladay | Jan 2 18
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