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3 Answers

Are these calculations wrong?

Hi all; we're building a 2300 sqft ranch with a basement for a total of 4600 sqft of conditioned space in climate zone 4-A. The slab is 4" concrete with R15 under it. The foundation walls are 8" concrete with R15 against them. The rest of the walls are aerated concrete with insulation for a minimum of R21.5 - 11.5 for the block and another 10 for the foam. The windows have a low .20s U-factor and a SHGC of .26. Most of the windows face East with a few facing West and North. There is only one small South facing window. We will be using an ERV for ventilation.

Asked By Michael Grundvig | Apr 22 18
0 Answers

Sloped ceiling insulation

I have a story and a half home that we are remodeling. We also added a garage with bonus rooms above. We are climate zone 6 in Gillette WY. We taped all OSB seams, are adding 2” of rockboard insulation with 3/4 rain screen and Lp smartside lap siding to the exterior and used ThermalBuck to fur out our windows. We will also be using Ecoseal Plus to air seal interior framing.

To the point:

Asked By user-7005570 | Apr 22 18
8 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
10 Answers

Small addition with helical pile foundation in Toronto Canada

Hi GBA,

I am an architect in Toronto. My client is a contractor who wants to build a small one storey addition using helical pile foundation instead of continuous foundation to save on cost.

The finished floor is raised above the grade by about 21".

My questions:

-Can I use chicken wire to support the fibreglass insulation in the floor joists as it would be difficult to finish the underside of the floor with plywood I think
-Do I need a air-barrier like tyvek under the fibreglass insulation

Asked By Lowell Lo | Apr 22 18
3 Answers

Can Housewrap 'melt' under steel siding?

I am installing metal siding on a new construction Home and planned on installing Hydrogap by Benjamin Obdyke underneath. The siding contractor has expressed concern that the paper or the dimples on it may melt.
Has anyone ever experienced housewrap 'melting' from the suns heat.

Asked By user-7015584 | Apr 22 18
6 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
0 Answers

Inadvertent vapor barrier?

I live in MN and have a 12'x16' porch addition that I'm about to insulate the vaulted ceiling. I'm calling the porch a 3-1/2 season porch since I'm installing electric base board heat which allows me to heat the room, but only when I intend to use the room, which may not be that often in the dead of winter. The scissor trusses are just 4/12 exterior pitch with a 2/12 vaulted ceiling and 7" heel height at the wall line, so not a lot of room to meet R value requirements here.

Asked By BobPv | Apr 22 18
6 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
9 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
8 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
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