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2 Answers

Foundation Waterproofing & Insulation Treatment

My new home design has an 8' basement and an attached garage with a 4' foundation. Is the garage foundation poured at the same time as the house or separately? On the basement foundation walls I'm planning to use spray-on waterproofing, board insulation, and a dimple mat. I'm not sure how to treat the vertical edge condition where those materials would start/stop. I used Sketchup to help myself visualize what's happening. Do basement exterior materials wrap under the garage footings and continue along the basement under the garage slab?

Asked By Bryanw511 | Apr 20 18
27 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
0 Answers

Basic vapor barriers question (kneewalls)

I've been reading GBA on air barriers.

Basic building science question that I'm hoping you can help me understand:

From a vapor/moisture perspective (ie, ignoring the 2x thermal barrier), what are risks to hanging polyiso on kneewall AND on roofline in a kneewall space? How much airflow is needed to reduce those risks of 2x vapor barrier?


Asked By Emerson | Apr 20 18
14 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
7 Answers

Mini-split energy usage

I thought I would offer some energy usage I had this winter with my Mitsubishi mini-split. Some info

Units: Mitsubishi MSZ-FH12NA H2i and MZ-FH15NA H2i heat pumps.
Location: Just North of NYC
99% outdoor temp - 12 degrees F
Heat load - 26,000 BTU

Month Degree Days KWh KWh/Degree day
Apr 12, 2018 824 997 1.20
Mar 14, 2018 817 978 1.19
Feb 12, 2018 1035 1450 1.40
Jan 11, 2018 1248 1773 1.42
Dec 11, 2017 751 870 1.15

Asked By WPmichael | Apr 20 18
1 Answer

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).

Asked By Irene3 | Apr 20 18
4 Answers

ECO Insulating Glass

Does anybody know anything about ECO Insulating Glass or had experience with their product?

Asked By Lucas Durand | May 1 10
10 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
24 Answers

Roof underlayment for vented roof with standing-seam metal roofing

Im nearing the end of construction of a high efficiency timber frame hybrid house I'm building for my self and have a low slope roof question that I would like some opinions on. Roof pitch is 1.5/12 (7 degrees)

Our main roof structure consists of timber rafters, 20" I-joists, dense pack cellulose, 1/2" plywood sheathing taped to the walls as air barrier. We drilled holes all over the roof to dense pack the cellulose from above (as our interior finish was installed on top of the timber beams as soon as they were installed.

Asked By Scott Benson Climate Zone 7A | Apr 9 18
13 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
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