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

Siding house in Maine

I am stripping and resideing my house I was looking at a product called prodex insulation it says it works as a vapor barrier as well as a high r-value what do you think of this type of product thanks

In Energy efficiency and durability | Asked By David Bernard | Feb 4 16
4 Answers

Waterproof, durable and easily removable panels?

Hello! First time here :)

I'm 25 years old, own 4 rental properties which i do all repairs and maintenance myself. As i have become more fluent in everything that comes along with doing that, i am now ready to do a fix and flip. Or i like to think of it more as a conversion. I have many questions and would love some dialogue in the future of what i want to accomplish.

My main focus is going to be making the house as maintenance free as possible. Super functional, strong and smart.

In Green products and materials | Asked By Silas De Vries | Feb 3 16
35 Answers

To crawlspace or not to crawlspace?

We are a group of four builders in Quebec breaking ground on a new construction this summer. We’ve been arguing over the niggly details for three years as we try to cobble together the most common sense, super-efficient, affordable house possible. As we seem to be proving, the discussions on how to build can go on forever...

In General questions | Asked By William | Jan 20 16
5 Answers

Wall assembly

I am not sure this is the correct place to ask this question but here it is. I am building a new home in NW Wyoming. I will have a sealed and conditions crawlspace under half the house. I have installed a radon system. The crawlspace has a poly sheet under a rat slab. The hvac is located in the crawlspace. Would it be a good idea to have the returns for the bedrooms and baths to vent into this crawlspace. It will also be insulated on the walls internally with rigid foam.

In Mechanicals | Asked By Charles Cloud | Jan 29 16
30 Answers

How to reduce radon level in my house?

When I first bought my house a couple of years ago the radon test was conducted in the first floor (bi-level house on concrete slab, all above grade) showed 3.5. A couple of years have now passed and I have since replaced all the windows and sealed all the gaps I could possibly find. Last week I did the same test again (using the same setup as my home inspector) and it was 12.1, ouch! Does it mean I made the first level too tight? What are my options to fix it?

In General questions | Asked By Joe Blanco | Jan 22 16
31 Answers

Which Weather Resistive Barrier behind new masonry?

I'm coming up on a project involving cladding Structural Insulated Panels (SIPs) with a full-thickness veneer natural stone wall. So, from the outside in, it will be stone - 1" gap - WRB - 6.5" SIP panel.

Question: Which WRB is preferable?
Context: I am in northwest Ohio.

The following page on this site's Product Guide lists a number of products, but links only to manufacturers' info: http://www.greenbuildingadvisor.com/product-guide/cat/water-resistive-ba...

In Green products and materials | Asked By Andy Chappell-Dick | Jun 11 13
10 Answers

Blower Door Results -- room for improvement?

Hi,

I had a blower door test performed as well as thermal imaging taken.

My home is 3300 sq ft of finished living space, 1600 sq ft of unconditioned basement and about 1200 sq feet of unconditioned attic (the remaining roof is cathedral ceiling).

My blower door test came back at 3050 cfm. The tech said that to get down to 2350 cfm would be "perfect" and that I was about 30% above optimal but that it, in his estimation, we were at the point of diminishing returns outside of caulking some areas we identified as leakage sites.

In Energy efficiency and durability | Asked By Justin Brown | Feb 2 16
3 Answers

open cell or closed cell

I have a pole barn that is covered in metal . It has a cement floor,insulated garage door,it will be a/c only ,an its in central fla. One contractor wants to use closed cell at 11/2''. Number 2 guy wants to do closed cell on roof an open cell on walls [2x6]. Number three guy wants to do the entire building in open cell. I,ve read alot of info on these products, I,ve talk to guys about it an I,m still unsure. I,m leaning towards the closed cell but iI,m not sure about the thickness of it. also the closed cell is the lowest price [still pricey] I,d your thoughts on this ..

In Energy efficiency and durability | Asked By bill metzger | Feb 2 16
12 Answers

New home HRV with massive shower/hot tub and range hood

I am building a new 3500 sq/foot home in New England. Well the 3500 does not count the finished basement of another 1000 nor does it over the "attic" space. The house is being framed now and we plan on spray forming the rafters. It has zip system on the exterior sheathing & taped. So the house will be tight.
Here is my issue... the house will have a "gourmet" kitchen which translates to a 48" range with a crazy 150,000 btu cook top. If you use the standard rule of thumb if 100cfm for 1kbtu.. that is a 1500 cfm externally mounted blower for the range hood.... yea..

In Energy efficiency and durability | Asked By Ken Leach | Jan 31 16
11 Answers

Fastening strapping for steel roof

For my simple gable roof, I will be installing exposed-fastener steel roofing atop 2x4 strapping atop Grace Tri-Flex underlayment atop OSB sheathing atop trusses 24" oc. Everything I've read indicates that screws would be best for fastening the strapping, as they offer far greater withdrawal resistance than nails, but I haven't found any recommendations on the best fastening pattern. Would using two 3-1/2" exterior deck screws at each intersection between the strapping (laid broad side down) and the truss top chords be best?

In General questions | Asked By Jeff Cooper | Feb 1 16
Register for a free account and join the conversation


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