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7 Answers

Where are commercially available VIG windows? Are they vaporware?

When I first read about vacuum-insulated glazing (VIG) several years ago, I got really excited; R-10+ windows!! I've been checking every couple of months since to see if they were commercially available and they STILL don't appear to be.

I've got my 100+ year old home almost up to passive house standards with air sealing/insulation. The foreclosed-upon house flippers that we bought our home from installed the cheapest builders grade dual pane windows they could. These are the weakest link in our home's energy efficency.

Asked By David D | Dec 12 13
14 Answers

What materials meet code for "flash and batt" on my ceiling?

I have an unfinished basement and I am looking to add about 5" of insulation to fill up the joist bays on the ceiling. The bays are 7 inches deep and will soon have around 2" of foam.

I am wondering if I would be able to fill the bays with Roxul and cover the entire ceiling with house wrap.

The reason for the roxul is that if necessary it would still be possible to access what's in my ceiling (wiring and some pipes), without the negative effects on air quality of the fiberglass.

I understand I can trim the roxul with a knife to match my very uneven 80 year old ceiling joist bays.

Asked By Robert Wan | Jan 12 18
2 Answers

Rim Joist External Insulation and Air Barrier - How To?


I plan to recess my rim joist so that 2" EPS can be added as a thermal break. This will be flush with the studs so my sheathing can cover the whole area. Pretty standard.

I want to bring my vapor retarder (Intello or Membrain) out and around the rim joist so it attaches with the vapor retarder on the inside walls. This should result in a seamless air seal from foundation to trusses. Again, pretty standard.

My first question is, does the 2" EPS go on the inside or outside of the vapor retarder and why?

Asked By Lance Peters | Jan 21 18
8 Answers

Radon 9.3 pCi/L even after radon mitigation-is this OK??

Hi. I am having elevated ( 9.3 pCi/L) radon after mitigation done. I have an encapsulated crawl space ( insulated, air sealed, dehumidifier ) with piping running under vapor barrier-which terminates to an outside radon fan connected with a 4"PVC pipe. Would like to find out if it's Ok to install drainage ( perforated black pipe) piping under vapor barrier ( in encapsulated crawl) for radon mitigation. The piping is spilt off of a main trunk ( no continuous circle) to different sections under the crawl.

Asked By hotandhumid | Jan 22 18
5 Answers

Where can I get a forced air heating wall vents that can be 100% sealed shut?

What's a good source for forced air wall/ceiling vents that can be 100% sealed off by the building residents (for example if a room is not in use)? The typical wall vent has lovers that only kinds sorta block flow and make a lot of noise doing it.

This would be for forced air systems, for example those with 4" metal ducting, or 4" flexible ducts.

Asked By Bryce Nesbitt | Jan 22 18
12 Answers

Header hangers vs. jack studs: Thermal bridging?

Advanced framing articles all seem to advise the use of header hangers instead of using jack studs. The idea is, less wood and more insulation in the wall, and better the thermal performance.

Has anyone studies whether the thermal bridge of a jack stud is better or worse than a header hanger? A jack stud is very large by comparison, but a header hanger is a relatively heavy gauge piece of steel that bridges right from sheething to drywall.

Beyond the thermal bridge, could a cold spot behind the drywall cause moisture issues or condensation on the interior surface of the wall?

Asked By Lance Peters | Jan 21 18
0 Answers

Finishing a finished basement

We purchased a brick veneered ranch home in the St Louis area about a year ago. The home is about 44 years old. The brick is in very good condition, but doesn't have weep holes at the bottom. In several areas that I can check there is an air gap between the brick and sheathing of the 2 x 4 framed wall of the house. This gap appears to be 3/4 to 1 inch. Currently the basement is finished except for 2 utility rooms. The finished areas have 1/2 inch drywall over 1 x 3 or 2 x 2 furring strips attached to the foundation wall.

Asked By Mark F | Jan 23 18
5 Answers

Minisplit vs Wall heater for raised ranch

Thanks to everyone who contributes to the blogs here, I have been reading everything on the site for years.

I have a friend with a small raised ranch which is heated with baseboard electric heat (!) and I'm helping him move toward something else. My suggestion is a minsplit with the head located in the living room which is fairly open to the dining area and kitchen. By locating it fairly centrally the head will also provide some heat to the three bedrooms and bath. The electric baseboards will supplement that - they are used to cold BRs (out of necessity).

Asked By Albany Landlord | Jan 22 18
8 Answers

Avoid higher SHGC windows?


Asked By user-6994996 | Jan 22 18
0 Answers

addition to half inch plywood battens for rain screen question

This is Craig again adding to info on question just asked. My siding will be lp smart side which is structurally strong enough according to some codes to be installed directly over studs with no sheathing. Eight inch lap with six and a half inch reveal. Also the studs are 16".

Asked By cragged | Jan 22 18
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