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12 Answers

Blown in air duct sealing and individual run testing

My home has return air in the attic which is relatively accessible and supply air in the crawlspace, some of which isn't very accessible. I had a blower door and ducting tests that revealed huge leakage. we applied mastic to everything accessible and fixed a big leak. We retested and got down to about 25% leakage and at the point the contractor said it was the best they could do.

Asked By Mark Renfrow | Feb 5 11
3 Answers

~10 degree difference between upstairs and downstairs rooms

I live in a 2 story single family ~1700 sq foot home where there is an uncomfortable 10 degree difference between the floors in the winter (too cold upstairs) and the summer (hot as hell upstairs).

We have a single thermostat on the main floor. Setting it to 72 in the winter leaves the upstairs around 65 and a sole bedroom in the front corner of our house is a few degrees cooler than that. That bedroom is what I need to address and it only has a single duct running to it. The temp slowly drops as the night goes on, leaving it quite chilly the next morning.

Asked By Matt Duffey | Jan 6 16
8 Answers

How to improve insulation in the corners of the house?

I live in a 1987 bi-level house and recently a thermal scan showed some cold spots in the corners and between the walls and ceiling and floor (as in pictures attached). However those spots are very difficult to access from the attic due to the slope of the roof, on top of that the attic has blown-in cellulose installed a few years ago, so it's almost impossible to navigate there for me. I am just curious if there is any method to improve insulation from inside the house instead of from the attic. Any other suggestions are very welcome! Thanks!

Asked By Richard | Jan 5 16
3 Answers

Temporary cathedral ceiling improvement

I live in Nova Scotia, Canada (Climate zone 6) and I own a 1950’s cape style house. The roof line is insulated with very thin batts and a previous owner had cellulose blown into the small attic at the peak and into the floor area behind the knee walls. The knee walls also received R-20 fiberglass batts. These efforts appear to have helped, but the weak point is still the sloped ceiling. During the winter, there is often snow left on the top 2-3 feet of the roof and on the bottom 4-5 ft of the roof, but the area in between is always the first to melt. See attached image.

Asked By Mark Fredericks | Jan 6 16
4 Answers

Emercor insulated rim board: “Do not insulate”?

I'm finishing my walkout basement, so I've gone the route of 2" XPS direct on the poured concrete walls, framed off an inch, and then filled my stud bays with Roxul Comfortbatt. I've got some leftover bags of Roxul and was going to throw some up in the rim joist, but as I made my way up thereI noticed a stamp on the rim board that says "DO NOT INSULATE!". They're insulated rim boards made by Emercor and I believe they provide an R-20 rating. So my question - would it really be bad to place Roxul against the rim board?

Asked By Mark | Jan 5 16
3 Answers

I-cut vs. modified I-cut in housewrap for window installation

Preparing for window installation where the housewrap has already been installed and we will use Dupont FlexWrap for the sills.

Dupont's instructions specify a standard I-Cut in the housewrap where the bottom is cut flush with where the sill will be, but it says that a Modified I-Cut is also acceptable.

Asked By Nick | Jan 5 16
1 Answer

Good non-venting range hood?

I'm looking for a non venting hood for tight house with HRV exhaust in kitchen. Range is electric. Any ideas?

Asked By Ben | Jan 5 16
11 Answers

I have a new home under construction in NE South Dakota (cold Zone 6)

I have a new home under construction in NE South Dakota (cold Zone 6). Exterior walls are 2x6 with 1/2" 5-ply plywood.

My insulation contractor will be dense packing cellulose in the walls. He uses a 6 mil polyethylene for the netting. My concern is the netting is a vapor barrier, allowing very little wall drying to the inside, only to the outside. Your thoughts and comments would be appreciated, Thanks.


Asked By Matthew | Jan 4 16
19 Answers

Insulating ceiling during winter construction?

Our house is currently at the stage where they are about to start interior framing. Unfortunately this means that there is a giant hole in the envelope (the ceiling!) and they are wanting to run temporary heat as it is quite cold (a typical daytime temperature this time of year is about 15F). Of course you can pump a lot of heat into a structure and not have it get too warm when you have no ceiling and a vented attic.

Asked By Nick Hall | Jan 1 16
3 Answers

Insulating a truck roof

This is only a small 1940 Chevy cab roof- just bought some 1/4" closed cell foam w/alum on both sides- they claim its Low e, but I am not expecting it to be perfect, just maybe slow the suns rays a little and also to lower that roof bottom so the headliner material will blend into the sides better? My idea is that I will attach the cloth headliner material directly to this stuff, but my instinct tells me it would be best to have an air gap between the bottom of the steel roof and this foil/foam.

Asked By George | Jan 4 16
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