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14 Answers

Radon is 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.

In GBA Pro help | Asked By Hotandhumid | Jan 22 18
0 Answers

Kitchen Hood

I’m in BC. I’m trying to figure out if a kitchen range hood is compulsory as I have been led to believe. I tried reading some of the government building code docs but they are not written in plain English and I really couldn’t figure out what they were burbling on about.

In Building Code Questions | Asked By TracyPTM | Jan 23 18
4 Answers

Half inch plywood battens for rain screen?

My contractor put up the first three quarter inch 1x4s today and there isn't quite enough room for my siding around the windows and doors. If I had another quarter inch I'd be fine. My question is will I have a strong enough wall if I use 1x4 half inch 5 ply fir plywood battens over inch and a half roxul using the heco topix therm screws made for inch and a half foam board? I would use three inch siding nails that would go through the battens and into the studs a half inch.

In Green building techniques | Asked By Cragged | Jan 22 18
1 Answer

Composite Foundation Walls?

Hello all,
After belittling my state for it's poor building codes, builders and lack of innovation in my last question, I came across this product and am really intrigued:


In my state, erected in half a day with the sill plate and waterproofing. Cost is slightly higher than a poured foundation, but when I take into account the waterproofing is included, I think it will be a wash. It is fairly new though, and I like leading, not bleeding edge. Curious what Martin, Dana and the others think of it (or if you would use it).


In General questions | Asked By Michael | Jan 23 18
7 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.

In Green products and materials | Asked By Bryce Nesbitt | Jan 22 18
3 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.

In General questions | Asked By Mark F | Jan 23 18
6 Answers

BEopt results

Tried using BEopt for my house and the results were a shock, somewhat. I live in Zone 4 in Maryland and was concentrating on the things I know will be occurring in the near future, attic insulation and wall retrofit insulation.

According to BEopt, the biggest insulation bang for the buck was the wall insulation. Putting in R13 of cellulose with Grade 3 installation produced a drop of about 500 therms per year. (I assumed Grade 3 installation was appropriate, since 1) it will be a retrofit and 2) I have a severe lack of faith in contractors.)

In Energy efficiency and durability | Asked By Jeff Towson | Jan 22 18
17 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?

In Energy efficiency and durability | Asked By Lance Peters | Jan 21 18
8 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.

In Green products and materials | Asked By David D | Dec 12 13
9 Answers

New house CZ3, ducted HVAC & air handling design questions

2500sf single story 3 bedroom north bay, California house with conditioned rat slab crawlspace. 3 bathrooms, family rooms with a gas fireplace, "great room" kitchen/DR/LR is 30x42.

Plans call for 2x6 walls with 1" of well sealed foam (exact type still tbd), 500sf of casement windows and french doors with sub-.30 ufactor glazing, unvented 6/12 exterior pitch scissor trusses.

In Energy efficiency and durability | Asked By Rob Hunter | Jan 21 18
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