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14 Answers

Are "Energy Nerds" in agreement on this?

"PV's are cheap enough now to remove the need to super insulated houses"

Asked By tech1234 | Apr 19 18
9 Answers

Furr-UP instead of furr-down to include ducts in the envelope?

Hi all,

I'm building a new home in south Louisiana and I've been lurking here for a few week soaking up some energy efficiency building techniques.

One of the biggest points I see on here is to include the HVAC system in the insulation envelope. But, that isn't standard practice in Louisiana for new construction ( as in, NO ONE does it in my area). I get the deer-in-the headlights when I even mention a closet unit with ducts installed in furr downs. This also goes for Framers and Home Designers

Asked By Jiggernaut | Apr 18 18
3 Answers

Open cell vs closed cell in a basement?

Hi All!
I am looking to insulate the basements worth of band joists in Northern Vermont (climate zone 6A). There's a couple different things going on here and I want to be sure I'm not goofing it up.

Asked By David Bailey | Apr 19 18
2 Answers

After the fact roof air sealing

Hello all,

Asked By Randy Williams | Apr 20 18
12 Answers

Wall assembly for an old church in Vermont

A client has an old un-insulated church in Central Vermont. She want to insulate the whole thing and turn it into a house. The builder wants to do this wall- assembly. I am concerned about dew point issues and trapped moisture. The walls are currently 2x5 studs with no insulation. Thoughts?

Asked By Robert Swinburne | Apr 18 18
11 Answers

Minisplit for a small room

I'm considering a mini-split install in our house. I'm in Austin TX, so it's a climate that requires significant cooling. I have calculated loads and I have questions about what happens if one has a mini-split running in a low load room. It's a child's bedroom and the doors are closed all night.

The room has internal walls on 3 sides and just one 3x5 window. Currently the load calc shows it at about 3300 BTU (of course that is at design temperatures of nearly 100°F and 72°F inside).

Asked By James Howison | Apr 18 18
5 Answers

Frustrated with local HVAC contractors - should I outsource the design?

Hi everyone. We're building a pretty large house here in the SF Bay Area, and having a devil of a time trying to find an HVAC contractor who'll actually design things using calcs and not eyeballing it. When I finally got one to do a manual J, he had to quit the program due to a family member with a terminal illness.

Asked By mike myers | Apr 18 18
23 Answers

Insulating kneewall slopes from above

Unfortunately we are having to fix some poor quality work by insulation contractors.

How should we build baffles, or what kind of baffles/vents should we buy, to maintain >1” vent for 5’ sloped ceilings above a kneewall, which can only be accessed from the top attic?

Asked By Emerson | Apr 17 18
12 Answers

Mini Split sizing feedback

Howdy all wanted to gauge your thoughts on Mini Split sizing

House facts:
- Built in 1955
- 1008sqft feet
- Single level ranch
- Poured concrete foundation with full basement, unfinished.
- First generation Corning/Owen Fiberglass batt insulation in walls, probably r-11
- r-30 batt insulation in ceiling installed within the last decade..
- White Cedar siding, laid over some kind of particle like panel material coated in black as sheathing.
- Multiple single pane windows with older retrofitted storm windows, two newer double paned windows.
- Ellenville, NY

Asked By evantful | Apr 14 18
1 Answer

2 or 3 Coat Traditional Stucco Application with Drain Cavity

Mineral wool outside insulation is becoming more common in residential in my location. I favour this over rigid insulation by far for many reasons, but I'm trying to figure out a best approach for traditional stucco applications.

Asked By DarrenKC | Apr 19 18
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