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2 Answers

Insulating exterior electrical box from inside

In my laundry room wall is the electrical box for one of my exterior lights. That wall cavity is open and I would like to insulate it from the inside. Getting it from the outside is difficult for me because of obstacles.

Asked By JakeNY | Feb 20 18
8 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 Zane Bridgers | Feb 19 18
24 Answers

Insulation upgrades

Hi Everyone.

Thank you in advance for your feedback, you have all been so helpful.

Zone 5A (coastal Mass) house.

I have an older 3200 sq ft home with a mix of well-pointed fieldstone foundation and poured concrete. The 1000 sq ft attic is currently air-sealed in most places, and has a mix of fiberglass batts and cellulose for about R-30. I have 10 recessed lights in attic, which have the LED airtight retrofits with gaskets, but are not covered in cellulose. The recessed fixtures are IC-rated. The remainder of the home has vented cathedral ceilings (sigh).

Asked By Justin Brown | Jan 22 18
0 Answers

Mitsubishi minisplit secret advanced settings

This is more an invitation to share than a question per se. I recently installed a two-zone Mitsubishi minisplit system in our home. One of the two indoor units is ducted and its blower continued to run even after the temperature set point had been reached. I understand this is normal operation for these units (and maybe for all/most minisplits?). I also realize there is a reasonable to case to be made to run the fan continuously even when heat/coolth is not being provided. However, I didn't want the fan when the heat/cooling is not on.

Asked By Chris Stratton | Feb 20 18
22 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
8 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
6 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
2 Answers

Fiberglass window choices for new build in Colorado

Hi everyone,

We are building a new home in Colorado, 7100 ft, south facing, energy efficient, single story. That is the short story. We are only considering fiberglass windows. The choices are Alpen 525, Marvin Integrity, Miguard Ultra and new to list Kolbe Forgent. In terms of energy efficiency: U, SHGC, VT the best is Alpen, made just outside of Denver, but no local vendor. The rest have local vendors for support.

Asked By LYDIA SEGAL | Feb 19 18
19 Answers

Cold climate basement insulation and code questions

I live in SE Wisconsin (Climate Zone 6) in a 1930s house that has a currently unfinished cinder block basement with a concrete slab floor. The basement is unconditioned but stays at or above 55 degrees in the dead of winter. Basement walls are 95% below grade, and there are some small windows at the top of the walls. The house is heated with hot water radiant heat but there are no radiators or other heat / HVAC sources in basement.

Asked By Navigator16171 | Feb 19 18
7 Answers

Insulating an unfinished basement ceiling in a 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
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