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!


1 Answer

Marc Rosenbaum will offer another online course

Marc Rosenbaum will offer his 10-week online course on Net Zero Energy Homes again, beginning on March 11.

Marc sent me an e-mail:

"The inaugural Zero Net Energy Homes online course had 50 students and was a great learning experience! We’re doing it again starting March 11th.

In General questions | Asked By Martin Holladay | Jan 29 13
4 Answers

Any recommendations for a particular type/brand of wall mounted electric radiator?

Is their a particular brand of wall mounted electric radiators that tend to be more efficient at distributing warm air into a room as compared to traditional floor mounted types? Thanks.

In Green products and materials | Asked By Matthew Michaud | Jan 27 13
11 Answers

Blower door testing with IR thermometer or smoke stick

Can I rely on using only an IR camera during a blower door test to find air leaks in the building envelope of a very tight new construction home?

We will be conduction our first of planned 2 or 3 blower door tests to achieve the Passive House standard of 0.6 ACH@50 in southern Maine. This first test will be done with the building envelop completed, windows and doors installed, air sealed all gaps, but before plumbing, electrical, insulation etc trades begin work.

In PassivHaus | Asked By Roger Normand | Jan 25 13
2 Answers

Deep Energy Retrofit

This isn't so much a question as a suggestion for those renting a basement apartment and looking for cheap approaches to a deep energy retrofit. The added bonus is we don't have to breath in fumes from the upstairs wood stove now! Images speak louder than words...

In Green building techniques | Asked By jessie pratt | Jan 29 13
0 Answers

Building Cost Estimator

Here is a free, easy-to-use, house building cost estimator. Asks a series of questions about size, material, finish, location, etc, then gives a breakdown of costs for each house component, for material, labor, equipment, and total.

http://www.building-cost.net/

Click on START CALCULATOR

Here's an sample result for a small simple house. The formatting is messed up, but you get the idea.

I would be curious if any professional contractors on this forum can vouch for whether it is roughly accurate or not?

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

In General questions | Asked By Jack Woolfe | Jan 29 13
1 Answer

Would this insulation method work?

I notice all the pictures of exterior rigid foam is overhanging the concrete foundation by the thickness of the foam. Is there any reason why it can not be installed flush with the concrete foundation,(the area where the bricks would normally go) and to just have the 1x4 strapping and siding overhang the foundation wall?
This way if you used metal flashing and insect screen it could be caulked right to the concrete foundation.

In Energy efficiency and durability | Asked By bert matter | Jan 29 13
3 Answers

Insulating a stepped foundation from the interior

I have a basement room that I'm planning to insulate. It's new 2x6 construction but the foundation is 15 years old. It's in zone 6. It's stepped with the west wall being half 8ft and half 4 ft of poured concrete, a south wall being 2ft and an east wall being a 1/2 ft off the floor. I insulated the exterior of west wall with 2in of XPS from the outside while digging it out for a drain. That wall had been getting wet, but is now very dry due to the drain work. I'll also be building a wall to seperate the garage from the room and insulating above the garage.

In General questions | Asked By stephen edge | Jan 28 13
3 Answers

What is the best method for insulating a crawlspace ceiling?

I have a vacation home in upstate NY, that has fiberglass batts in between the crawlspace ceiling joists. I want to remove the fiberglass and replace it with something less rodent friendly. The crawlspace floor and walls are encapsulated and the space is dry. Any suggestions?

Also should I spray foam the rim joist area?

In Energy efficiency and durability | Asked By David Jackson | Jan 29 13
13 Answers

Double Wall

I am planning on building a new house and am looking at using a double wall. Outside wall will be 2x6 studs on 16 centers with ½ plywood sheeting and rain screen. Roxul R24 in cavity’s. Inside wall I will use 2x4 on 16 centers. I will leave a 1 inch gap between both walls. Is this enough or two much? In the 2x4 wall cavities I will install Roxul R14. I have been doing some research hear on the internet and I have read that sometimes the 2x4 studs warp because of no sheeting on the opposite side of the drywall.

In Energy efficiency and durability | Asked By Sam Fowler | Jan 22 13
3 Answers

Protecting crawl space slab foam

We have a 4' crawl space that has eps foam+vapour retarder for a 'slab.' what are some cost-efficient options for protecting the foam and poly? i imagine the homeowner will want to use the space for some storage. p.s., concrete is not an option....thanks again, gba!

In General questions | Asked By erik olofsson | Jan 28 13
Register for a free account and join the conversation


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