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 >
9 Answers

2/12 cathedral roof replacement

Hi,

I have a shingled 2/12 roof that needs to be replaced it is a cathedral ceiling. It has no dormers or right angles to it, the size is about 40' by 20'. I am in Vermont so i have serious ice dams which i would like to minimize but heres the catch i am not looking for the 15k to 30k option. I am looking for the most reasonable balanced option under 10k. I have received a few quotes.

1. Strip roof, ice and water shield, architectual shingle ~5500k

In GBA Pro help | Asked By mark kessler | Feb 23 15
1 Answer

Flash and batt in northern Iowa

We have a new post-and-beam home. We've put in 3" of ccSPF in the walls and are thinking at adding R-13 kraft-faced batts over this in the loft. Because of the way the exterior walks are framed, there is 2" of spray foam between the interior studs and the exterior sheathing, except at the posts and beams. Is there going to be a potential moisture problem with using the faced batts?

In Energy efficiency and durability | Asked By New House | Feb 23 15
9 Answers

Frost-Protected Shallow Foundation question

Hey,

I live in southern Vermont and am starting to build my home this summer. I'd like to build a FPSF and I am also planning on doing the build over a couple summers, starting this summer and continuing next year.

I haven't been able to find any info out there in regards to building a FPSF and not having a finished structure over it for the winter, as I know the system relies on the homes heat to some degree to keep it from heaving.

Any one know if this will be a problem, to have the foundation in place over winter without a house on it?

Thanks,

Moses

In General questions | Asked By Moses Draper | Feb 18 15
4 Answers

Old house, ice dam resolution

Hello There,

I have read with great interest many of articles and conversation with fellow readers. Here is a brief description of my situation.

I own half of a 1891 ballooned-framed duplex located in Saratoga Springs, NY. The building has a low slope roof with parapet front and side walls, and drainage in the back into gutter. Since it was built, the house has suffered from ice dams. In fact, when I purchased the house two years ago and performed renovation, the back side framing lumber had significant rot.

In Green building techniques | Asked By Sonia Yau | Feb 22 15
8 Answers

XPS or PVC under base plate

I'm looking to start framing in our basement. The house is 15 years old, and did have some water leakage (some small puddles could form during big rains... We had crack injections done this fall to alleviate the issue), but no flooding yet (knock on wood).

I thought I read somewhere that you could use XPS insulation to put under the base plate of the wall. It seems like a good idea (a 1" insurance policy should the basement begin to flood).

In Green building techniques | Asked By Andrew Wayland | Feb 22 15
6 Answers

Dipping a big toe in solar

I was wondering if there was a good guesstimate tool for helping to figure out "how much Solar I need"?

I am thinking about adding Solar to a spec. house and was interested in Solar since the price point has dropped so much. I will be doing the panel install myself with my crew and have the electrician wire it up.

In General questions | Asked By leo kloop | Feb 20 15
11 Answers

What is the best sealant to use for airsealing?

I know I want seal as many air paths as possible. Is there one particular sealant that works best for things like drywall to studs, spaces between double studs, rigid foam to studs and PE film?

In PassivHaus | Asked By Donald Lintner | Jul 28 09
12 Answers

EPS or polyiso? Layered, taped seams?

I have found a supplier for EPS (plain EPS, no coatings) or Polyiso (foil faced on one side, white non-reflective on the other side)

1.) The polyiso is double the price. However, it is effectively better at insulating to my knowledge. I assume it should be my pick?

2.) I don't want to use more than 2" of foam on the exterior. With either product, I believe it will be advantageous to layer two 1" thick pieces with staggered joints. If I don't have the time I will simply buy the 2" thick and call that good.

In Green products and materials | Asked By Nicholas C | Feb 22 15
4 Answers

Insulation help needed?

I am in the process of building a house and thought I had a good plan for insulating, but want to know if I can do better. My current method I planned on using will pass code, but i figured if I can increase R-value effectively, why not. Better to do it now. I live in zone 4a. We have hot summers and fairly cold winters.

1 story
2x6 construction
Vinyl siding
Tyvek house wrap
Osb sheathing
Fiberglass or denim batts in stud cavities for R-value of 21.
Drywall
Have a full basement, will be unfinished for awhile.
Attic will have like R 50 blown fiberglass

In Energy efficiency and durability | Asked By Nick Lynn | Feb 21 15
4 Answers

Possible electrical ground out or short?

On the 7th of January, my townhouse electricity started cutting out (around 7 times). There was some wind in the area and cold temperatures, near zero. It stopped and soon after I would get shocked if I touched a lightswitch or my pet's nose. My power usage has doubled, but that may be due to the temperature change. It is my first winter in this place. However in the past, I have never had such a huge increase in usage. It went from 537 kwh to 937 kwh and increased again this bill to 1087 kwh. Could a ground out cause the static buildup? (The floors are carpeted.)

Thanks.

In GBA Pro help | Asked By Sheleen Feldhaus | Feb 21 15
Register for a free account and join the conversation


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