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3 Answers

New construction in Madison, CT (Zone 5)

I'm reading conflicting opinions on (central) humidifiers. New construction with open-cell spray foam insulation. Is a humidifier needed or advisable?

In Energy efficiency and durability | Asked By Justin | Jan 6 16
16 Answers

Are indoor air monitors worthwhile?

I have recently gotten notices of the release of Blueair and Awair. I am sure there are others on the market as well. Are indoor air monitors worthwhile? Accurate? Useless? I know that inside a tight house air quality can be more of an issue than an old leaky house, but is monitoring the best way to address the potential problem or some other approach?

In Green products and materials | Asked By A Lange | Dec 25 15
2 Answers

How do I repair this mudsill joint?

It looks like there is some kind of parging that is now crumbling, i could break it apart with a screwdriver pretty easily.

In Energy efficiency and durability | Asked By Alan | 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!

In General questions | 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.

In General questions | 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?

In General questions | Asked By Mark | Jan 5 16
9 Answers

Light-weight thermal mass option for passive solar?

Hi, I am trying to design a single 40' long high cube storage container to be converted into a living space. It will be completely off-grid, insulated very well with closed cell insulation. I want to take advantage of as much passive solar heating as I can. The container will have great un-obstructed southern exposure. I want to keep construction weight down as much as I can.

In PassivHaus | Asked By Cameron | 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.

In General questions | Asked By Nick | Jan 5 16
1 Answer

Under-floor hot water coils

I have a hot water underfloor (pex tubing) loosely run in between the joists (as if you uncoiled a new hose) & not close to floor with a foam board attached at btm of joists. It is very slow to reach set points & will over ride up to 2-3 degrees. I was considering attaching the metal plates with the tubes touching the floor but labour intensive with 3 ft crawl space & folks say it will be noisy. Friend suggested to remove u clips that hold the coils & use bubble back insulation to push coils close to floor & then add more insulation Roxall R 20 to bottom & then finish off with the foam board.

In Energy efficiency and durability | Asked By Peter | Jan 5 16
80 Answers

Geothermal nightmare

We truly hope you can help us. We had a geo-thermal closed loop system (into the river) put in and it went online March 2012. WaterFurnace Super DeHeater, 4 Multi-Aqua mini-splits (included for AC) and an air-handler (included for AC). 3200 sq ft home with baseboard and in-floor radiant heating. $34,000 and we have had nothing but problems.

In GBA Pro help | Asked By Colleen Nicholson | May 30 13
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