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10 Answers

Replace AC with a heat pump?

I've recently inherited a house in Virginia mountains, climate zone 6, that's been used as a three-season retreat. I want to keep it open in winter. Heating is via coal-guzzling electric baseboards. Conventional AC w/ exchanger in unconditioned 3rd floor attic and flexiducts.
1) Can i replace the AC w/ newest generation heat pump like those used in mini-splits? Local HVAC folks are not familiar w/ the technology, since climate is too cold for conventional heat pumps

In Energy efficiency and durability | Asked By Jerry Knight | Apr 1 15
4 Answers

Does 1x3 strapping reduce thermal bridging?

For those not familiar with the term strapping it is 1x3 boards.
It seems to be a New England thing to install 1x3 perpendicular to ceiling joists prior to installing drywall on the ceiling.
Does this practice significantly reduce thermal bridging of Rafter/ceiling joists in a cathedral ceiling application?

In GBA Pro help | Asked By Dirk Gently | Apr 3 15
6 Answers

Question re furring strips, XP drywall, and finishing basement over 3" of polyiso

I have used recycled roofing polyiso panels (1.5" stuff), staggered them, and going to foam the gaps where I can and use acoustic sealant ("the black death") on gaps too small for foam.

Here is a big question, I want to put furring strips horizontally and just mount drywall over that:
1. Is it OK to just go with furring strips and not build out full 2X3 or 2X4 framing. Wasn't planning to fill the gap with anything between drywall and polyiso

In GBA Pro help | Asked By Apollo S | Mar 23 15
3 Answers

Is it wise to put a product like Drainwrap behind a layer of rigid insulation?

We are getting ready to remove the existing layers of siding from an old (100yrs. +) home that appears to have diagonal board sheathing attached to the studs.

Our intention is to blow cellulose into the stud bays, then cover the board sheathing with Drainwrap integrating the window flashing into this layer, then adding 1" rigid foam with seams taped, and finally adding 1x furring strips and either Hardi or Lp lap siding.

The project is waterfront on a coastal bay in Maryland. The windows in the home are vinyl replacements in original wood frames.

In GBA Pro help | Asked By mike labesky | Apr 1 15
4 Answers

Holding back cellulose

I'm just about done air sealing our attic and getting ready to blow in cellulose. For a few sections I need to make a vertical "wall" of it. One part is where the stairs are. As discussed in another thread part is a flat ceiling, then a vertical slope down to the stair ceiling. I'm going to put fiberglass batts on the vertical sections, but want to blow in cellulose on the flat part. I'm thinking of stapling window screening to the top plate of the actual wall and then staple it to the ridge beam of the house.

In Green products and materials | Asked By Jeremy M | Apr 2 15
1 Answer

Looking for information on Apex Block. Is the company still in business?

Has anyone used Apex Block? Can you recommend an alternative, since I can get nowhere trying to contact them?

In General questions | Asked By Jonathan Bankert | Apr 3 15
2 Answers

Softlite and Quaker Windows

So I've got some quotes on the above two brands and about crapped my pants when I saw the difference in prices. Neither window is something super spectacular, but when you have over 200 sq. ft. of glass on one wall alone, it's kind of hard to justify $100 a sq. ft on glazing.

The Softlite's from what I can tell have the following ratings for a double hung window:
U-.27,
air leakage .02 scfm @ 25mph,
SGHC of .28.
Cost for a 3050 Twin: ~$920 each

The Quakers have these for a double hung : U-.26
air leakage .16 scfm @ 25 mph
SGHC as low as .21
Cost for a 3050 Twin: ~$340 each

In Energy efficiency and durability | Asked By Michael McArdle | Apr 2 15
6 Answers

With taped exterior sheathing, is there any benefit to caulking each stud bay?

I have 1/2 cdx sheathing taped with zip tape. I takes the sheathing to all window rough openings as well. I was planning on caulking or applying acoustic sealant to the crack between the sill plate and the bottom of the sheathing and again at the top plates. The sheathing was not glued or gasketed at these joints.

Since all of the other sheathing joints are securely nailed to blocking and taped with ZIP tape I presume there is no point to caulking the stud bays?

In Energy efficiency and durability | Asked By Rick Van Handel | Mar 31 15
5 Answers

Gravel under concrete footing

I am trying to finalize several aspects of the foundation design for the high-performance house we’ll be building in central Vermont starting in May. Typical of the region, our house site, which has a 7% slope, is near the bottom of 600 foot ‘mountain’ and we expect it to be moderately wet (Buckland very fine sandy loam soil that is only “moderately well drained”).

In Energy efficiency and durability | Asked By Timothy Denny | Apr 1 15
4 Answers

Tyvek and / or fanfold insulation under siding

I have a 1950s home and am adding new vinyl siding.

There is an option for Tyvek and / or fanfold insulation under the siding. My understanding is water will get through the siding so the main goal is to prevent water from reaching the sheathing. Tyvek seems to accomplish this. Is fanfold better or would both be better?

I have heavily insulated on the inside. I think the main potential problem with fanfold is to prevent possible moisture on the sheathing or between the studs. This is Iowa, hot humid summers with cold snowy winters.

In General questions | Asked By Erich Riesenberg | Apr 2 15
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