Q&A: A Forum for Green Building Experts and Beginners

Q & A Instructions

[Click map to enlarge]

The GBAGreenBuildingAdvisor.com web site has a wealth of articles on a wide variety of construction topics. Before posting your question, you may want to check out the articles on this page: How To Do Everything. You just might discover an article there that provides the information you seek.

Please register for a free account or sign in to ask and answer green building questions.

If you want to post a question, the usual rules of courtesy apply:
1. Be nice.
2. If you can't be nice, be polite.
3. If you can't be nice or polite — well, please be brief.

To attach a photo or illustration: Under the box labeled “More explanation,” look for the words “File attachments.” Click that, and you should be able to attach a photo.

Thanks for joining the conversation!

22 Answers

HRV duct set up

I am getting ready to install my HRV. I have been contemplating exhaust in the two bathrooms, three bedrooms, and kitchen area, with only one supply duct in the great room near my mini-split. 1300 square feet, one level, 3 1/2" exterior foam, 6" fiberglass batts, unvented sealed crawl space. The design person at the HRV store is said I should have supply to all bedrooms and just exhaust the bathrooms/kitchen. Climate Zone 7, so I am a little concerned about supplying all that fresh air to the bedrooms in the dead of winter.

Asked By Steve Vigoren | Sep 6 16
4 Answers

Sun Bandit solar water heater

Hello. I was reading the article by Martin Holladay entitled "Solar Thermal is Really, Really Dead" and enjoyed the discussions going back and forth on the topic of solar water heating methods. I am planning on building a small 600sq' SIP cabin in the area of Nelson BC (climate zone 6) next year and I found this product listed as being one of the most efficient for heating domestic hot water on the Canada Energy Guide site. It says it can also be used for space heating via a radiant floor system or perhaps radiators.


Asked By Scott Wilson | Oct 21 16
2 Answers

Zone 3 minimum wall assembly

New construction proposed 2x4 wall assembly.
Latex paint, 1/2" Sheetrock, BIB fiberglass, OSB, Tyvek wb,1" gap, stone or smart siding.
Doesn't this just meet the minimum requirements in Zone 3?

Asked By Mike Beckham | Oct 22 16
11 Answers

Air to water heating: flat plate with water storage or long copper pipe in water storage?

in an effort to make our house more comfortable, and to eliminate the drift of air we currently are in the opportune to raise the living room floor with a sub-floor and by doing so, include in-floor radiant heat.

plan is to:

raise living room floor (440 SF) by about 14 inches, with standard plywood and 2x12 timber.

on top, install R10 EPS insulation with 5/8 PEX/O2 barrier 6 inches on center, encased in 2.5 inches of sand/cement and 15 mm laminate flooring

Asked By Kevin Kersten | Oct 22 16
1 Answer

Best practice for stone siding over stick built walls

We are planning to apply 4 inch thick rubble stone siding over the lower level of our daylight basement home. We had originally planned for ICF at the lower level walls, partly to mitigate rain water and inward vapor drive risk brought on from the stone (which is south facing). As it turns out the ICF represents a substantial cost increase and we are considering alternative wall options (stick-built) for the above grade portion of the lower level wall.

Asked By Sean Hembree | Oct 22 16
15 Answers

can you create a blog on infrared heating panels?

People would benefit from knowing how infrared heating panels are more efficient, comfortable, and safer than conventional heating methods.

Asked By Iona Jonasson | Oct 19 16
4 Answers

Zone 3 roof dampening concern unvented attic

New home construction - roof design
asphalt shingle, 30# felt, OSB, 5 1/2" open cell foam. Should I be concerned about the design causing moisture problems over time?


Asked By Mike Beckham | Oct 22 16
17 Answers

Best building envelope approach for an owner-built home in northern Wisconsin?

Setting the Stage:

My wife and I purchased a vacant farm (no buildings) with a south-slope in far Northern Wisconsin and have been planning our next home for a few months. We would like to build a "pretty good house" that finds that happy place between great energy efficiency and economy. This would be an owner-built home on a basement foundation. Our forest has plenty of millable pine and oak that we intend to use as much as possible for the build (framing, siding, flooring, etc.).

Asked By Michael Sterner | Oct 17 16
1 Answer

Domestic hot water power demand is no longer an issue?

Traditionally, heating and cooling requirements have been the largest energy draw in homes. The ability to relegate heating and cooling to 2nd or even 3rd place in a home energy draw hierarchy is now possible with better building techniques, such as PH. It has been generally agreed that the new king of the draw is DHW. However, I wonder if that is still the case now that HPHW systems have hit the market. I live in a heating dominated climate. The maximum heating demand allowed per PHI is 4.75 KBtu/SF or 5.2 KBtu/SF per PHIUS+ for my climate zone.

Asked By Jonathan Lawrence CZ 4A New Jersey | Oct 22 16
1 Answer

Reducing wintertime ventilation

I have an Ultra Aire ventilator and dehumidifier (80 cfm) and a Panasonic ERV (20 cfm) that deliver outdoor air into my 3,200 square foot home. The Ultra Aire is installed in the basement and dumps air into a space near the central air handler. The Panasonic is on the second floor.

During the cooling season, I can easily maintain indoor humidity between 40% and 50%. During the winter, levels typically are in the mid 20% to 30% range.

Asked By Steve Knapp | Oct 22 16
Register for a free account and join the conversation

Get a free account and join the conversation!
Become a GBA PRO!