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7 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
7 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
1 Answer

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
1 Answer

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

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
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
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
2 Answers

Thermalbuck Insulated Window Bucks

A person on my thread about Roxul Comfortboard vs ZIP-R Sheathing suggested that I use this insulated window buck when using the Roxul system. I never knew this type of product existed, but I think they deserve their own thread.

Anyone have experience using them?

Asked By Scott Wilson | Apr 17 18
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