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70 Answers

Why haven't steel-framed homes become more popular?

I am in the planning phase of building a home in the NJ-NY area, Climate zone 5. As I investigate my options; SIPS, double wall stick 2x4 wood, 2x6 wood, ICFs, CMU, Larsen trusses, etc.. and the myriad of permutations to insulate each one (spray foam, cellulose, hybrid batt & flash, exterior rigid foam/iso panels, etc....) I came across STEEL. My goal is as high R-value as I can get within reason $$, with hope of upwards of R-30 final values. That said, I need some objective input.

Asked By Sal Lombardo | Dec 27 12
4 Answers

Storage space in attic vs. living area

Hi.

I have an old, leaky house and dream of a new energy efficient home of about the same size (1200 sf). Right now we use the attic and knee walls for storage. From what I have read, it is no longer considered energy wise to use attics in new homes. But, if we loss that space (and won't have knee walls), we will have to build more square footage to accommodate our stuff. That does not seem particularly green. Please advise.

Asked By Jen Weaver | Jul 24 16
9 Answers

We are building a 700-sq.-ft. cottage on southern Vancouver Island, Zone 4 Marine

The plan is to use 4 inches polyisocyanurate - R22.6 - (glass fiber covering) exterior insulation no sheathing except for earthquake walls. No insulation in the 2x4 wall cavities, tyvek on the exterior of the foam and vapor barrier between the polyiso and the framing. ls this ok or will we have problems. We have to present our wall assembly plans to the city and the city wants a vapor barrier but we are not sure if this is necessary.
Sandra Garraway

Asked By Sandra Garraway | Jul 22 16
2 Answers

Replacing insulation in basement

Hello, I have a 3 year old basment with 8ft concrete walls that was finished with 2 by 4's that are about 1/2 inch off the concrete wall and fiberglass batting was used as insulation which I don't believe is the correct material. If i want to replace this should i go back to the studs and perhaps do a spray insulation or is it best to take everything out and start afresh. At this point i do not have any mold/smell issues but also think it could just be better insulated. I am in zone 5/6, right on the edge. Thank you.

Asked By J D | Jul 21 16
56 Answers

Transoms and Ductless Minisplits

Hello,

I am trying to heat and cool my second floor with one 12,000 btu ductless minisplit. I have heard that this is possible if I keep the bedroom doors open during the day to facilitate circulation of the hot or cool air.

However, does it get uncomfortable quickly in the night when the doors are closed. If so, I was thinking of putting in operable transoms over the doors. The only problem is they are kind of expensive (~$275 from transomsdirect.com). Attached is my floor plan. I will be putting ceiling fans in each bedroom so maybe the transoms would be overkill?

Asked By Jimmy Nguyen | Mar 10 16
10 Answers

R-35 wall assembly for a 4C Marine climate zone

I am about to build on a 85" rainfall, 6000 HDD and no cooling system (I can withstand a little heat in summer)
http://en.climate-data.org/location/147654/

I'm thinking of (from outside in)
* 1" wood siding
* 1" of air gap with 1x3" furring
* asphalt paper as WRB and air barrier
* 3" 2pcf EPS as R10 sheathing,
* A 10" double frame wall filled with a total * of R-24 polyester insulation
* asphalt paper as air barrier and vapor retarder
* 3-4" interior wood finish

(see attached image)

Asked By Jose Castro | Oct 29 14
3 Answers

Is an air space between a ceiling and SIPs a problem?

I have a timber roof system that goes like this.
timber rafters
plywood with a flooring glued to it and fastened down on top of the timber rafters
suredeck membrane (to protect the plywood) and double as vapour barrier
2x6 strapping on top of the plywood to facilitate electrical
8 1/8" sips
synthetic membrane and peel stick for eaves protection
laminated shingles
Should I be concerned about the 1.5" space between the top of plywood and bottom of sips.
We are going to be extra ornery about air sealing the sips.

Asked By Marty Munroe | Jul 20 16
10 Answers

Attaching Roxul (Comfortboard 80) to exterior foundation wall

My wife and I are building a "green" home (mix of Passive House, Pretty Good House, and Net Zero). For the basement foundation (9' basement) we intend to use spray-on waterproofing then two layers of Roxul Comfortboard 80 mineral wool (3" + 2" = 5" total) on the exterior side.

Asked By Eric Whetzel | Jul 14 16
7 Answers

Insulating a suspended floor: Caulk the seams or not, and is cellulose okay?

A friend of mine is building a tiny house on a trailer in Austin, TX (Climate Zone 2A), and has questions about insulating the floor.

First, should the seams of the floor framing be sealed with acoustical sealant before installing the insulation, to prevent air infiltration and increase insulation performance, or is some air movement good to prevent moisture accumulation and mold?

Asked By Michael Bluejay | Jul 16 16
6 Answers

SIP roof vs Truss roof

Trying to resolve a friendly dispute with a local carpenter friend.

On a 1,500 square foot roof area with 380 square feet of soffit overhang area (24" soffit).

If one would attempt this with trusses, OSB sheathing, 24" soffit overhang framing, sheathing the soffit, installing R-40 worth of insulation (spray foam). What would the ballpark cost of this be?

There is NO dispute on timeliness. The above SIP roof can be installed in 2 days and the SIP overhangs 24" on each side so it's an instant soffit. No way that a truss roof with all the above can be completed in just 2 days.

Asked By Peter L | Jul 16 16
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