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32 Answers

Unvented 5/12 pitch slate roof built with Zip sheathing and closed-cell spray foam insulation

Hello,
I am Homeowner building house in Port Washington , NY, ( Long Island )
My Architect will try to go for passive house certification , so "She" needs to be air tight and super insulated .
"She " will have ERV system and attic floor will not have any insulation , so temperature will be balanced throughout interior of the house
Exterior walls is constructed with 3/4" zip sheathing over 5-1/2" LSL Versa studs ,
Interior cavity of wall studs will be 3" of closed cell spray foam and balance of 2-1/2" will be open cell spray foam

In Energy efficiency and durability | Asked By Joe B | May 15 16
5 Answers

EPA study finds induction cooktops to be no more energy efficient than regular electric cooktops

I was reading this review: http://thesweethome.com/reviews/best-portable-induction-cooktop/ and it mentioned this study from the EPA in 2014: https://www.gpo.gov/fdsys/pkg/FR-2014-12-03/pdf/2014-28212.pdf

It appears that induction is right around the same efficiency level of regular electric cooktops. This also calls into question the frequent claim of induction giving off less waste heat -- that would be impossible, if it's no more efficient.

This would remove induction from the list of energy efficient technologies, and relegate it to basically a luxury/convenience.

In Energy efficiency and durability | Asked By Nick Welch | May 17 16
4 Answers

Adding insulation to stucco wall in Los Angeles area home

I'm retrofitting a home near Pasadena, CA and am beginning to look at options for insulating the currently-uninsulated exterior walls and could use some advice. The home was built in 1963, and the wall assembly appears to just be stucco on lath, then building paper, then studs, then drywall. There's no sheathing and no lateral bracing except for some diagonal 2x4s at the corners. (please see photos)

In GBA Pro help | Asked By Chris Stratton | May 17 16
11 Answers

Revisiting a wall in Climate Zone 5A

Construction is on the horizon in our "pretty good house" in Iowa, Climate zone 5A.

Although I know our wall isn't perfect, we have chosen the materials for a variety of reasons. Currently from exterior to interior we have:
-Hardi-plank siding
-1x4 furring strips for rain screen
-Tyvek WRB
-2" rigid insulation, currently XPS
-Sheathing, currently OSB, taped
-2x6 framing, open cell spray foam in cavity
-drywall, with latex paint

My questions after reading and re-reading the prevailing thoughts on this site are:

In Green building techniques | Asked By Thomas R | May 10 16
1 Answer

What should be done to replace siding but leave window?

The original windows on this project were attached to the building by face nailing through an integral brick-mold. The windows were subsequently replaced with "replacement" windows, which left the existing window frame and brick-mold in place. The brick mold was wrapped in coil stock and fastened with nails along the edge of the brick mold perpendicular to the sheathing. The facilities manger wants to replace the existing ugly and degraded siding with a quality vinyl.

In General questions | Asked By josef chalat | May 17 16
2 Answers

I am giving up in Illinois

For the past 6 months we've been trying to find a qualified contractor who can design and install a Mitsubishi hyper heat system for a 3K sqft gut rehab home.

We are trying very hard to break away from the traditional horse cart technology of a furnace and blower.

It's practically impossible to find someone who works on these new inverter-based systems. First off is the issue with Manual J and Manual S. The city requires this, and I understand that the inverter systems may not fully align with the Manual J/S norm.

In GBA Pro help | Asked By Ismail Mohammed | May 16 16
8 Answers

Soffit vent screen size?

I am at the tail end of a major remodel / expansion, and my soffit vents are a detail yet to be completed. As built, the framers simply drilled 1.3" holes in the vertical board between the rafters sufficient to meet Accuvent's recommendation for vent area.

The house is in Southern California, so we not only have bees and flying termites, but a variety of other critters that could cause trouble.

The smaller I go on the mesh size the better it is at screening out small insects, but it comes with a cost: reduced airflow.

Can anyone comment on a good screen size for this instance?

In General questions | Asked By Mike Simanyi | May 11 16
6 Answers

Electric radiant heat, extra insulation

Hello. I've installed electric radiant heat in a customer's kitchen which is partially over a laundry room and partially over a crawl space. Crawl space is well insulated with 2" xps on the floor and closed cell spray foam on the walls. The customer still feels that the in floor warning over the crawl space is cooler. Think it would be worth while to install the foil backed insulation that's used with hydronic in-floor heating to help? Besides putting a heater in the crawl space, I can't think of much else can be done.

In Energy efficiency and durability | Asked By Daniel Chidley | May 15 16
2 Answers

Toolbase.org guide to FPSF

http://www.toolbase.org/PDF/DesignGuides/revisedFPSFguide.pdf

Does anybody know why this site is down or where it moved to?

John

In General questions | Asked By John Burk | May 15 16
3 Answers

Using polyiso and XPS rigid insulation in a vented vaulted ceiling

We are considering using cut-and-cobble rigid insulation in a small 4'x15' vaulted ceiling. This is a small part of a larger roof replacement. The contractor who originally finished this bonus room did not insulate it well.

In General questions | Asked By Rick C | May 16 16
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