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5 Answers

Slab on grade house and garage : can I pour the floors once the shell is up?

I currently have the footings frost walls (4'), and the sandy base filled in and tamped for the slab. The house is roughly 50'X30', 2 storey, and the floor joists can technically span 30' (24" deep trusses), but the plan has a "supporting" wall roughly in the middle of the width to keep the floor span at 15-17'.

The garage is 30'X40', with no supporting walls (wide open).

Asked By Mai Tai | Apr 21 18
1 Answer

Is this a vapor-permeable air barrier?

1960's home... wall construction is as shown, with face brick on the back side. Silver faced material is thin (maybe 1/8" thick).

I did not notice originally, but in good light, once can see what may be perforations in the surface.

Does anyone recognize if this is a vapor permeable sheathing material?

Asked By Rossn1 | Apr 21 18
2 Answers

Details for 4-foot-wide brow roof?

CZ6A, 45 degrees Lat., Ottawa ON

Finishing up the details of our new build. I'm going over my plans with my Engineer and he has concerns about the integrity of my brow roof design. Specifically, he's worried about snow load and sag (creep) over time. This is for the south facing wall and its large windows.

Do any of the builders here have experience with design details for a 4ft deep brow roof on a flat two story wall?

Asked By Lance Peters | Apr 22 18
5 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).

Asked By Irene3 | Apr 20 18
6 Answers

Need to replace clothes dryer - what technology?

My wife informs me that our electric clothes dryer is nearly kaput. Should I replace it with the same kind?... as I understand the technology hasn't changed in years. I also hear of newfangled tech like condensing (ductless) dryers, heat pump dryers, and of course gas dryers.

What is a efficiency / cost savings / payback period of these alternatives? We live in New Hampshire, so heating-dominant climate. Electricity costs me $0.17/kWh, propane is currently going for $1.90. Would probably cost $200 to bring a line over to that side of the basement.

Asked By Tyler Davis | Apr 21 18
11 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

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?

Thanks.

Asked By Emerson | Apr 20 18
5 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
30 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
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
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