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9 Answers

Retrofit / renovation to bring heating costs under control

Hi folks,

Thanks for creating this great resource for newbies like me to learn!

We're actually near Toronto, Canada, but I think you could consider us Zone 6A for your purposes. We bought our ~2000 ft^2 1981 home last year and suffered a horribly cold and expensive winter, so we'd like to take steps to bring that back in control.

Asked By Justin Allport | Aug 20 15
5 Answers

Do I need to follow the insulation code in any circumstance?

I am converting the sun room to bedroom.
The room is isolated from main building and faced with garage. Only 200sqft room.. no bathroom will be installed in the room.

The room have nothing but the roof above.

Asked By mansig yoon | Aug 26 15
5 Answers

Attic Ductwork

I live in Nashville, TN climate area 4A

My issue is my attic gets so hot in the summer months and my heat pump runs a lot but does not cool very well. This is a duplex home with each side having around 980 sq foot living space.

Asked By Janice West | Jul 11 15
8 Answers

Does leaving a service cavity on the inside of a double stud wall make sense?

Would there be anything wrong with the following assembly? From exterior to interior: Siding, furring, rigid insulation, sheathing (air seal and WRB), 2x4 stud wall, gap, netting stapled to inner studs. 2x4 stud wall, and finally drywall. The outer 2x4 stud wall and the gap would be filled with cellulose, but the inner 2x4 stud wall would be empty to allow easy wiring and plumbing.

This design seems to have some clear perks. Removed thermal bridges. You get a service cavity. The inner wall supports the netting, so it won't need excessive stapling.

Asked By John Ranson | Aug 27 15
9 Answers

Wall stack up opinions - using rigid foam as air barrier between double stud wall?

Hi,

I'm in climate zone 6A looking to build a partition wall between an attic bonus room. One side of the bonus room will remain as cold storage, and the other side will be heated by minisplits and resistance backup. I'm looking at building a double 2x4 wall separated by rigid foam. The exterior wall would be framed 24" o.c. to maximize insulation. There will be no plumbing or wires in the exterior wall. The interior framed 2x4 wall will be framed 16" o.c. and will contain wiring, and will possibly be plumbed for a sink.

From cold to warm, here is what I'm proposing:

Asked By Rick Van Handel | Aug 24 15
7 Answers

Zola Windows

Hello,

Asked By william dempsey | Aug 25 15
4 Answers

Advice needed to insulate an existing block wall from the exterior

The local parish hall has a 40' x 44' addition with exterior walls of 8" concrete block and a bow truss roof/ceiling that was built in the 60's. On the interior, there is no additional wall build-out or insulation, just exposed block. We are planning on insulating the exterior walls and adding blown in cellulose to the existing fiberglass roof insulation after air sealing all penetrations.

Asked By Jon Michael Wyman | Aug 25 15
17 Answers

Is it advisable to use nail base insulation panels over a roof insulated with closed cell spray foam?

We are renovating an old railroad station, turning it into a residence and are gearing up to put new roofing on the building. Built in 1888, the building has massive overhangs on all sides and the rafters are mostly 2x6s with 4x6s spaced about 8' apart supported by large brackets. We had planned to use closed-cell spray foam insulation in order to get the maximum r-value in the relatively shallow rafter bays. Also, we want to maximize the available head room in the second floor rooms. The underside of the roof will also be the ceiling with t&g beadboard installed directly to the rafters.

Asked By Jodi Gunderson | May 29 15
1 Answer

Add external rigid insulation to a roof over a cathedral ceiling?

Yes, I know there are many resources on this topic. I’ve done a lot of reading on Fine Homebuilding and Green Building Advisor. I just can’t put all the pieces together.

We have a 30’x33’ 1-1/2 story cape cod with first floor living space, 2nd floor unconditioned space with knee walls and 2 doghouse dormers along the front. 25 years ago we added an extensive low-pitch shed dormer at the back vented to the ridge vent and installed drywall cathedral ceilings in order to add 2 bedrooms and a bath upstairs. No skylights, no recessed lights. We are in southwestern PA, climate zone 5.

Asked By Carolynn Friday | Aug 24 15
13 Answers

How can I solve an uninsulated basement slab energy loss?

I built a supper insulated house on a foundation that was not. I currently live in climate zone 5A in central Illinois, the house itself has R30 basement walls, R40 first floor walls and R60 attic. Double stud framing, air barrier is at the house sheathing. The house itself is 4400 sq ft total of enclosed space, 2100 first floor and 2300 basement. At the moment my home is heated and cooled with a single point source ductless mini split on the main level with a Zhender ERV for mechanical ventilation. It performed pretty well this past winter and does well this summer.

Asked By Joseph Betz | Aug 19 15
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