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3 Answers

Questions about humidity control in unconditioned space

Two locations: Zone 3A, coastal N.C. (fishing cabins converted to a non-profit retreat facility—insulated and heated, but no AC); and Deccan Plateau in central India —wet, continuously humid 3-month monsoon and scorching hot & dry 4-month summer (HVAC nonexistent).

Primary question: how can mold and mildew issues be prevented and/or managed in an unconditioned space?

In GBA Pro help | Asked By David McNeely | Oct 5 16
1 Answer

Control algae growth without harming bees?

I have a fountain, about 25 gallons, that's very popular with birds and, to my surprise, bees. What can I add to the water that will control algae growth but won't harm the bees?

In Green products and materials | Asked By Ray Sten | Oct 6 16
4 Answers

Mixing EPS and XPS--zone 5

I am currently building a house in zone 5. On the walls, I am doing 2x6 with cellulose and 3" of rigid insulation on the exterior. I couldn't decide between EPS(cost effective) and XPS, so I purchase enough for 1.5" layer of each. Since EPS is a little more vapor permeable does it matter if it's the inside layer or the top layer? I do plan to have a house wrap on the outside of the foam.


In Energy efficiency and durability | Asked By Michael Brackett | Oct 6 16
9 Answers

Off-grid weather station to measure build site conditions

I've purchased vacant land in hilly terrain and will be building a residence and workshop next summer.
I'd like to setup a solar or battery powered weather station to learn more about the microclimate.

Knowing, e.g., typical temperature and humidity swings on the site will help me answer questions like: "how much insulation does the workshop need to prevent condensation / rust on tools?"

Does anyone know of an off-the-shelf battery or solar powered weather station that can measure temperature, humidity, and wind speed?

In Green products and materials | Asked By Kevin Lynagh | Jul 26 16
1 Answer

Crawl space insulation climate zone 6B, 7000 feet elevation, low humidity.

I have a question regarding an existing home in climate zone 6B located about 7000 feet in elevation?

In GBA Pro help | Asked By Gary Macdonald | Oct 6 16
4 Answers

Basement wall insulation in Climate Zone 5


I am hoping someone can help me determine the correct way to insulate my basement. After reading many forums, completing a lot of research, and even contacting the builder of my home I am confused more than ever.

I'm located in central Illinois zone 5. The front of basement is fully below grade with poured concrete foundation. The back of the basement has daylight windows with standard 2x6 framing on top of a 3' foot foundation wall. The 2x6 framing is currently filled with unfaced fiberglass and poly on the interior side. The home was purchased new and was built late 2011.

In Energy efficiency and durability | Asked By Arthur Sperry | Oct 5 16
3 Answers

Finishing a basement room below grade in Climate Zone 5

Hello, I have a questions regarding finishing below grade walls in zone 5. We have been researching the correct steps to finishing these walls but seem to get different answers depending on whom we ask. I went to our county and state code websites but didn't get clear answers there either. I would love to get some feedback to hopefully simplify the answers for us. Thanks for your time!
Christy W. Madison WI

1. Is it best to leave a gap between the framing and the concrete below grade wall?
2. What kind of insulation is best, Styrofoam, spray foam, etc for below grade walls?

In Building Code Questions | Asked By Christen Ward | Oct 4 16
1 Answer

Rebuilding old passive hot air solar panels

I am trying to rebuild a passive hot air solar panel manufactured by Great Western Solar company (no longer in business under that name). The box is aluminium with lascalite fiberglass for the transparent cover. Because the cover, angle aluminum and fibeerglass sheet seems to be glued down and then riveted, for the life of me I can not get it off. So, my idea was to cut out the lascalite sheeting and install a new type of plastic cover and overlay new angle aluminium over the top of the old.

In GBA Pro help | Asked By Tom Gordy | Oct 5 16
3 Answers

Moving air from warm to cold room

Hello. I would like to move some of the warm air that builds in one southern exposure room on my second floor to my north end 1st floor. I am thinking of a simple 4" duct with inline fan that is piped from the source to the cold area. I was told to actually send the cold air upwards into the warm room which then would aid in drawing warm air downward. Any thoughts on how I should go about this? Thanks in advance.

In General questions | Asked By Matthew Michaud | Oct 5 16
5 Answers

Forming eaves vents with I-joists

My house's roof is going to be a shed roof formed with 14" i-joists. They'll sit on beveled plates on the attic floor. At the top and bottom, there will be LSL blocking angled perpendicular to the plane of the roof. The blocking has to be full height, and can only be v-cut in the center third for ventilation.

In Green building techniques | Asked By John Ranson | Oct 5 16
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