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!

6 Answers

Question on ballpark renovation costs

I know it varies and there are a lot of variables, however.....
Anyone give me a ballpark cost to totally gut my 1 1/2 story , 2 bedroom cape cod style house? Everyroom except the only bathroom, upstairs?
It is 850 square feet, and I am looking to have all drywall replaced, baseboards, trim, ceilings. In the kitchen, when gutted, I might as well have new cabinets, counter, and back splash, with middle grade cabinets, no granite, etc.. currently there are only 7 uppers, and 5 lowers (cabinets).

In General questions | Asked By Dave Mac | Feb 14 17
2 Answers

Open cell vs. closed cell for hot roof in Florida

I just bought a 25 year old home in Jacksonville. 2 Story framed home off grade. We are considering replacing the fiberglass insulation in the attic with spray foam on the underside of the roof sheathing. My goal is to move make the attic more of conditioned space because 1) the air handler and all the A/C ducts are in the attic 2) We're just finishing install a number of recessed cans in second floor ceiling.

In Green products and materials | Asked By Paul Tasillo | Feb 14 17
11 Answers

Questions about furnace air returns

Regarding furnace air returns.
1. Can I get central air installed, have a gas forced air furnace?
2. Would I benefit from fresher air in the home if I had an air exchanger installed?

House built 1920, had coal furnace, converted to gas, had the big octopus in the basement with gravity heat.
Because of that only one duct upstairs in hallway,
None in 2 bedrooms, doors were kept open.
Only one return in living room floor.

Have had forced air furnace for 17 years, live in a electric municipality where electric rates are low, 20-30/month.

In General questions | Asked By Dave Mac | Feb 12 17
10 Answers

Metal standing-seam hot roof

Hi I'm building a new home for our family and wanted to run our roof design by you as my concern is moisture/ condensation. Essentially we have 2x12 members on a low-sloped 2 5/8" over 12 large 3500 square foot roof. I'm planning on insulating with 7" of closed cell (More if recommended) and no vapor barrier because of closed cell not needing it. The roof deck will be covered with Ice and Water HT and then have a standing seam metal roof installed on top of the ice and water. We are located in Massachusetts. One debate is do i use CDX , OSB Standard or advantech.

In GBA Pro help | Asked By Michael Carreiro | Feb 12 17
4 Answers

How do I insulate an unsheathed exterior wall that has 6" stone veneer?


I am in the process of renovating a 1920 bungalow in Kansas City, MO., zone 4 or 5. I wish to make it as tight and efficient as possible, maybe even net-zero with a 6.3 KW grid tied PV system. I have it gutted now as the combination of neglect, a failed tile roof and unique original construction shortcomings made saving any of the interior impossible.

In Green building techniques | Asked By Jim Gottsch | Feb 13 17
14 Answers

GBA blog dated 2015: "How to Insulate a Foundation"

I've read many articles from various reputable sources as well as this one from GBA http://bit.ly/2lAt69b and I have a follow up question...

Martin, you've recently replied to my retrofitting basement questions regarding insulating a 1974 bungalow in climate zone 7a, so thank you.

In General questions | Asked By Todd | Feb 10 17
1 Answer

Stone veneer or XPS?

Question I am building new house and have XPS 2" on exterior on foundation wall running below grade and above grade was wondering if anyone can give me some Technique
Was thinking about using a stone veneer on the concrete that is above grade anyone that I ask says need to remove the xps from the foundation wall on exterior to attach stone veneer question is there a way to attach stone veneer leaving xps on wall Thank you

In General questions | Asked By Boris Rubinstein | Feb 14 17
4 Answers

Multi-speed inline exhaust fan

Is anyone aware of an inline exhaust fan that has multiple speeds so it can do low continuous ventilation and on-demand ventilation?


In Mechanicals | Asked By John Ranson | Feb 12 17
9 Answers

Best way to reduce interior humidity in tight house?

I have been building and refining my "best practice" for 20+ years. I have built a house with walls wrapped in XPS foam (sheetrock-->2x6 with fiberglass batt--> osb--> XPS--> rain screen--> cladding). All XPS joints are taped. The roof is TJI cathedral with blown in open cell foam under plywood, under shingles. The sheetrock finishers had turned up the heat inside to 71 degrees and the temperature dropped last night to the upper 20's. I'm building in zone 4A. There is a conventional HVAC system with fresh air intake motorized damper.

In Green building techniques | Asked By mtndrew | Feb 9 17
3 Answers

Where is the best place to go to get a building science education?

I am a young builder looking to learn more about building science. I do a lot of research on the internet but I think my time could be better spent in a classroom, virtual or otherwise.. I've looked in to yestermorrow but would like something geared more specifically to building science. I subscribe to the fine Homebuilding podcast and building science corporation. They have really opened my eyes but I would like a more formal education.

In General questions | Asked By Spencer Shemwell | Feb 12 17
Register for a free account and join the conversation

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