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!


3 Answers

Zone 3/Central GA 12x32 weekend cabin on 36" above grade piers

Building Envelope Critique Please/Materials purchased and we're about to begin:
1) From interior: 1x6 T&G pine fastened directly to 2x6 studs 24" OC; R-19 fiberglass batts/caulked gaps & seams; 1/2" plywood sheathing; one layer 1/2" pink foam board/taped seams; 4x8 exterior panels. Where is best positioning for my WeatherMate Plus wrap?

In Energy efficiency and durability | Asked By Brad Skeeters | Mar 14 14
4 Answers

What is the best insulation for an unfinished work/craft room in the basement?

I have a basement workroom that I'd like to expand to a craft room for our kids, but it's currently uninsulated poured concrete and freezing in the winter. I was hoping to slap up something like a rigid board insulation, that could be left uncovered, but it seems even polyisocyanurate needs a gypsum board layer.

In Green products and materials | Asked By Laura Braceland | Mar 16 14
3 Answers

Trash organization?

Right now I have, in the kitchen, a roll-out cabinet thing with a trash can and recycling can. I also have a standalone "dual recycler" that I use as two compost bins, one for back yard compost and one for city compost (which can take things like meat). I'm not really thrilled with this mishmash arrangement, but there isn't a lot of space to steal another cabinet. The compost can currently blocks a small cabinet. Glass just sits on the counter by the sink, since there usually isn't much, and there's nowhere else for it to go.

In Green products and materials | Asked By Nick Welch | Mar 14 14
2 Answers

Are you familiar with the ducting option for heat-pump water heaters?

Since Alex has been pointing out the energy advantages of using a heat pump water heater (HPWH), I thought some readers might be interested in the approach I've taken with the technology. Instead of just scavenging heat from where this unit is located, I added duct work and a centrifugal fan to draw air from the two upper level bathrooms in my home so that the heat pump was "seeing" air from the occupied space. I also added duct work on the discharge side. In this installation, in addition to the energy savings, the following benefits accrue:

In Green building techniques | Asked By David Bearg, PE, CIH | Mar 15 14
1 Answer

2015 Solar Decathlon Latin America

I’m really excited that my hometown in Cali, Colombia was selected by DOE to host the first Solar Decathlon in Latin America in 2015. All the buzz is going to help promote sustainable construction to a much higher level.
http://www.energy.gov/articles/us-and-colombia-collaborate-first-solar-d...
http://www.solardecathlon.gov/blog/archives/category/solar-decathlon-lat...

In General questions | Asked By Armando Cobo | Mar 15 14
5 Answers

Insulating 1950's Tectum roof from exterior - Air barrier ?

I have a house built in 1957 that was originally a summer place on a lake. Climate zone 5, just outside of Chicago, IL. Roof is a timber (3.5"x5") frame at 32" o.c. with what appears to be Tectum I, 2" thick structural roof deck panels (2'x8' long). Current roof assembly yields me a whopping R3.5, which naturally means ice dam-nation every winter as we melt everything that lands on our roof. Apparently all previous owners did not care or did not know how to remedy.

In Energy efficiency and durability | Asked By Scott Grobarek | Feb 28 14
5 Answers

Bath fan ductwork - material and insulation (revisited) -

First, apologies if this should be under the "general questions" category

I saw some information from Riversong in response to a bath fan duct question asked quite a while ago (posted by Chris Johnston - Thu, 08/26/2010 - 14:57). The essence of the response was that plastic duct (glued, sloped) was somewhat insulative, and condensation would drip out (sloped out to vent cap) via the 1/4" per foot slope.

In Green building techniques | Asked By Randy Toni | Mar 13 14
1 Answer

Flat roof, non vented — What about furred space for slope?

I am building a non-vented flat roof in CEC zone 8/ DOE zone 3-92705. Roof structure will be structural sheathing on 12" I-joist. For slope, sheathing over 2x furring strips (1/4"/12"). I have read all the posts about various ways to insulate.

If the actual roof is something like a 2-ply SBS membrane and the insulation under the structural sheathing is a closed-cell flash-and-batt system, should I worry about the spaces between the 2x furring strips used over the structural sheathing for slope?

This space will not be vented. Will this space trap moisture?

In Building Code Questions | Asked By keith messick | Mar 14 14
1 Answer

Looking for a fire rated garage door

I’m building a new home in Everett Washington area and I’m looking for a source for a fire core (man) door from the garage into the house.
I’m looking for one that is 30x80 and that will pass a blower door test, possible passive house rated. Studio on top of garage design does not allow for a detached garage.

In Green products and materials | Asked By Paul Huntman | Mar 14 14
2 Answers

If you were to replace your windows what material would you use for the frame?

If you were to replace your windows what material would you use for the frame? And would you use a double pane with argon?

These are replacement windows for a hot climate.

In Energy efficiency and durability | Asked By Janet DeMars | Mar 13 14
Register for a free account and join the conversation


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