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5 Answers

Bathroom comfort

In Boston, zone 5A, in a 1100 ft^2 19th century condo.

We're turning a pantry into a second bathroom, a wetroom. The pantry is in a corner of the house that's currently pretty cold in the winter. Our home already has cellulose insulation, we spend only about $500/year on heating, and any large improvements would have to be coordinated with other condo owners, so I'm not sure we have much incentive to do a general energy retrofit.

In Energy efficiency and durability | Asked By Stephen Thrasher | Nov 1 13
1 Answer

Double stud wall & furring strips

Hi -

I am building a 900 sq ft house in south-central Maine. My wall bays are 10" deep (double 2"x4" stud walls with 1/2" plywood sheathing with Tyvek). There is no exterior insulation. I taped the sheathing seams and will be air sealing the stud bays, then filling with dense pack cellulose/drywall.

In Energy efficiency and durability | Asked By William Teer | Nov 2 13
1 Answer

Passive Solar & Thermal Mass

On the southern facing rooms having an exposed concrete slab works better for passive solar than a carpet covered floor during winter. Can one have too much exposed interior concrete or in other words, is too much interior thermal mass a bad thing?

During summer, is it beneficial to put down a throw rug of some sort to keep the sunlight from hitting the concrete floor and warming it? (Of course besides the exterior overhangs and window shades)

In PassivHaus | Asked By Peter L | Nov 2 13
5 Answers

Inground Gutter


I am finishing my basement and came across this article on inground gutters on Fine Homebuilding's site which Martin Holladay had contributed (and it is a new concept to me, but seems exactly what I need):


The description shows 6-mil plastic or better 1 foot below grade and attached to the basement wall with pressure treated furring and Tapcon screws. (See photo IngroundGutter.jpg)

In General questions | Asked By John Rousseau | Dec 26 11
5 Answers

Attic moisture problems

I live in Oakland, CA, near San Francisco. I have a 1920s building with a low-slope roof, 1.5” in 12, and an unvented attic with R-30 cellulose blown in. The ridge is roughly 3 feet high. A new roof was installed 8 years ago.

Recently I noticed mold in the attic on the roof sheathing and sides of the joists. There are no water leaks so I am lead to believe this is a condensation issue. I want to remediate the mold and want to make sure the mold does not come back.

I believe I have 3 options:
1) Re roof with foam board insulation

In GBA Pro help | Asked By Jeff Birnbaum | Oct 31 13
9 Answers

Dry unfinished basement subflooring: What is best method to avoid moisture problems?

Putting in a workout room. Floor is currently poured concrete and level.

What is the best way to mitigate possible moisture issues in the future? Some say 6mm plastic sheeting then underlayment then the click floating floor. To me this sounds like moisture will be trapped under the plastic and against the concrete into perpetuity. DriCORE has plywood on top of 1/4" waffled plastic problem w this is the plywood is susceptible to mold and rot.

What is the best approach. Want to use engineered hardwood or bamboo.

Thank you

In General questions | Asked By Pat Tucci | Oct 31 13
1 Answer

GBA website request: comment RSS feeds

If you look at almost any article here on GBA, you see a long string of comments that trickles in over a long period of time. There must be discussions going on in these threads all the time, that are completely hidden unless you happen to be looking at that article at that time. A comment RSS feed would allow this stream of buried comments to be easily followed. I recall seeing that this site is using Drupal, and it looks like there is a Drupal plugin that could be dropped in to enable comment RSS feeds: Comment RSS module.

In General questions | Asked By Nick Welch | Nov 1 13
8 Answers

Conditioned crawl insulation--best way to apply?

We are building a new home in NW Oregon (zone 4C) and I am planning a conditioned crawl. The design is based on a lot of reading here and elsewhere, hopefully it makes sense. We have carefully graded the crawl floor to a lowpoint drain and covered the floor with 2 inches of fine gravel. The vapor barrier (Moistop Ultra 6) will extend over the top of the stem wall and capillary barrier to be sandwiched by the mudsill. All the seams will be 6 inch minimum overlap and taped. I am installing 3 inch polyiso foam (R20) on the interior of the foundation wall, over the vapor barrier.

In Green building techniques | Asked By Dave Morgan | Oct 30 13
6 Answers

Spray foam fishy odor

Hello- We just had Gaco Western Wall spray foam installed last Wednesday. The first day it was installed it did not smell and the second day it still did not smell. Those two days the weather was cool and gray. On the 3rd day it was sunny and the house was heating up that is the day the smell started a fish odor. Our walls are not closed up yet. I have contacted the contractor he said this has never happened to him before. I also called Gaco and they said they would contact the sales rep in our area to come over to our house. The smell only happens in the midday.

In Green products and materials | Asked By Diane Fredricks | Oct 28 13
2 Answers

Pressure treated wood house framing

Are any homes built with pressure treated framing?

Is it allowed?

Any health issues?

There are parts of frames that do rot often enough to think PT framing would be useful. Showers toilet floors exterior wall plates window frame areas. Yes of course build right to start with but anyone who works on repairing these areas knows what and why I'm posting this.

Using a bit more PT wood per home would cost little to nothing.

In General questions | Asked By aj builder, Upstate NY Zone 6a | Nov 1 13
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