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

[Click map to enlarge]

drawing of climate zone map.gif

Advice can depend on climate -- Please specify in your question.

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

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!

Ask a Question >
2 Answers
Basement slab moisture barrier

I am finishing our 800 sq.ft. basement in Portland, OR (zone 4c). I am planning to lay a combination of carpet and linoleum and want to reduce the chances of mold from moisture that might seep up through the concrete slab, which varies in thickness from 2" - 4" in some spots. I have noticed a couple 6" diameter spots on the slab that seem moist during the rainy season, but no pooling of water.

Asked By Matty McDermott | May 16 13
8 Answers
How green is my cloud?

I can't verify, but I read sometime recently that there's less embodied energy in buying a CD than in storing it on-line. Which got me to thinking about these monster servers that must be sprouting like mushrooms. I have a vision of us all living in lovely net zero homes, served by our own individual off-site servers consuming a Fukushima's worth of juice.

No real question. Just wanted to share my cheerful thought before the weekend.

Asked By Dan Kolbert | May 17 13
27 Answers
I have narrowed my search for fiberglass triple-glazed windows to Fibertec and Thermotech — seeking comments about these two

I am building an Energy Star certified home with fiberglass, triple glazed, low e casement windows and slider/patio doors in Connecticut. I prefer using a Canadian company because of their expertise with fiberglass, triple glazed windows and sliders. I must have window specifications for the Energy Star certification, preferably NFRC ratings or at least independent U, SHGC and VT value ratings. Window ratings do not seem to be diificult to acquire but slider/patio door ratings can not be provided by some manufactures for fiberglass triple glazed sliders and French doors.

Asked By JOSEPH POLAND | Jan 15 13
19 Answers
Soundproofing Bedrooms

What's the general consensus for economically soundproofing bedrooms for guests/family comfort during normal daily life? I'm aware of using more than one layer of drywall, and would like to avoid this option.

Any ideas?

Thanks in advance for your advise,

Robert

Asked By Robert Car | Oct 15 10
3 Answers
Quickly listing neighborhood amenities by LEED category

I am working on several LEED for Homes Midrise projects which are pursuing points under LL5 Community Resources. LEED outlines several categories of resources, like:

Arts and entertainment center, Bank, Community or civic center, Convenience store, Daycare center, Fire station, etc.

Asked By Kris Knutson | May 17 13
5 Answers
Say you want a door but you also want to use it for solar gain. Is there a type of door style/material/size thats best?

I can't seem to get values for doors from manufacturers or when I do, the SHGC drops precipitously once you put the glazing in the door, e.g., Sungate 500 SHGC drops from .6 to less than .4 when put in a swinging fiberglass patio door. Of course glass size is limited to about 2 ft width, although the length is long. How I get what I need in SHGC in a south facing door. Do I change door style, size of door/glass, material, glazing brand, ? etc. Thanks

Asked By Lisa Young | May 16 13
3 Answers
Some help with estimation of wall assembly cost?

We are in the process of designing a passive house and are working with PH certified architect/consultant. But for now, builder's knowledge would be needed: a back of the envelope calculation for the cost /sf of this kind of wall assembly: fiber cement board w/ rain screen, fiber board, dense packed cellulose, OSB, dense packed cellulose, drywall. The wood framing will most likely be w/Larson trusses. The R-value we are trying to achieve is around 40. The house is a duplex with gross sf area of ~4500. Would be good to know the material & labor separately. Why do I need it?

Asked By Lucyna de Barbaro | May 16 13
2 Answers
Sealing a dry sump

My basement is fairly dry and well above the local water table
and hasn't had any water ingress over any of the major storm
events we've had, and has never had a sump pump. So I don't
really care about storm water; what worries me is the potential
for internal plumbing leaks as there's no way for the basement
to drain until it basically fills all the way up. So I'm
thinking of putting in a sump pump but into a small well that
*doesn't* connect to whatever gravel/earth/whatever is underneath
the slab -- it would be connected to the slab and sealed in and

Asked By Hobbit _ | May 16 13
14 Answers
Closed-cell foam on underside of roof with no AC: Do I need to vent?

I am working with a local energy efficiency contractor. They are replacing my old roof (which badly needs replacing) with a new roof. They will be spraying five or so inches of closed cell foam directly against the decking. This will fully seal my attic. My question is, how does this work if you do not have air conditioning in the house, other than window units in the bedrooms and one in the living room.

Asked By Rob Graff | May 7 13
1 Answer
Does anyone have experience with or an opinion of the Dow Powerhouse solar shingle and cathedral ceilings/ roofs?

The cathedral ceiling/roof is unvented, closed cell insulated. Will this solar shingle properly vent moisture upward from the plywood decking? Will there be any problems with running the multiple wiring conduits to the inverter in the basement?

Asked By JOSEPH POLAND | May 16 13
Register for a free account and join the conversation


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