Community: Green building techniques

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3 Answers

Need Roxul cover be entire to act as a rain screen?

In Zone 4, (Lawrence Kansas) we are rebuilding an 1883 house. For reasons of cost we have chosen not to take off the exterior clapboard, instead we are fitting 1.5" of high density Roxul between the studs and against the back side of the sheathing to provide a rainscreen. On top of this we will spray a thin layer of high density foam before blowing in another layer of dense pack cellulose to slightly built out studs.

Asked By Sacie Lambertson | Mar 23 17
7 Answers

Building a house in Greenville, SC — insulation and air sealing questions

Building a house later this year. Plan to live in the home 30+ years. So I'm interested in the "long term."

The House: 3,350sf above grade. Very very little shade on this house. Kinda like building in the middle of a field. Lots of sunshine bearing down. Galvalume metal roof with 3/4" strapping between metal and synthetic felt (TBD). Zip System for exterior walls. 2x6 exterior walls. I'm planning on ponying up for the super efficient Trane XV20i heat pump. Cement fiber siding painted white.

The Plan:
Foam attic with open cell to 5.5-6".

Asked By Farm House | Mar 15 17
5 Answers

References for best practices for green building?

What best practices manuals for would people recommend incorporating by reference into a building spec? Rather than reinventing the wheel, where possible I would like to refer to existing documents.

For example, I don't think I can put together something half as good as The Hammer and Hand Best Practices Manual for rainscreen details.


For reference, I'm building a slab-on-grade with double walls and a trussed roof in zone 5 near Rochester, NY.

Asked By John Ranson | Mar 21 17
1 Answer

Spray foam attic with cathedral ceiling

I'm considering spray foaming my attic for energy efficiency and elimination of dust. The attic currently has blown in fiberglass insulation originally installed when the one-story house was built in 1993, which I plan to get vacuumed out prior to spray foaming. Last year I had a metal installed with synthetic underlayment on my A-frame roof. I have seven soffit vents on each side of my home. I also have a cathedral vault ceiling, which limits access in the attic. No ridge vents only a few 18"x 18"square style attic vents placed across the roof for attic ventilation.

Asked By uberaustin | Mar 22 17
4 Answers

With a drainage membrane on exterior of foundation walls, is backfilling with gravel still recommended?

We're in an area where gravel runs pretty high in cost (monopoly effect.) On the exterior of our basement walls we'll have sprayed in place Tremco Tuff'n'dry H8, with Tremco Warm'n'dri drainage board installed prior to back filling. So is it still a no brainer to backfill with gravel or might we be able to skip this and save some cash? We haven't excavated yet, but soil in this area is classified as "silt loam" - in other words it's not a heavy clay, but it's not light, sandy soil either.

Asked By William Costello | Mar 19 17
4 Answers

Polymer Siding

We're planning a 1200 sf addition on to a small brick ranch in zone 5. The plan is for 2 x 6 on 24" centers with dense pack cellulose insulation followed by zip system sheathing then 2" of rigid foam, probably polyiso. We want to side it with Certainteed's polymer siding in the double seven rough shake style. I've read Scott Gibson's post and other commentary regarding the attachment of vinyl siding and I've spoken with Certainteed. Normally I would think that furring strips would work but this particular style is odd that it comes 57" long and obviously not going to work on a normal layout.

Asked By Skip Ward | Mar 17 17
10 Answers

How to attach vertical siding with a rain screen?

Is there a ventilated furring strip for vertical wood siding? Or, are there clips available? How does a horizontal furring strip not interfere with air circulation when incorporating a rain screen?

This project is in Climate Zone 3C.

Asked By BILL WOLPERT | Mar 15 17
5 Answers

This building technique seems to be suffering for lack of a name.

Having read almost every article I can about ways to put together a passive/prettygood house... having dived deep into AAC and CLT... I finally have come upon a wall system which seems to combine the simplicity of AAC/CLT with external insulation, the effectiveness of a PERSIST wall, and the cost effectiveness of conventional/smart framing. It just seems that this wall doesn't have a name (perhaps it is a modified PERSIST?)

Asked By Ethan T ; Climate Zone 5A ; ~6000HDD | Mar 14 17
1 Answer

Spokane, WA zone 5B rigid foam and drying


I'm a long time subscriber to Fine Homebuilding and follower of the website, and finally I'm able to put all of the knowledge to work building my family's new house this summer.

Asked By Andy Huska | Mar 15 17
1 Answer

How to best attach siding through 1.5" polyiso?

With continuous 1.5" polyiso over 1/2" plywood sheathing, can I nail wood siding through the insulation to the studs? I was trying to eliminate another layer of plywood. I am planning to use "Hydrogap" by Benjamin Obdyke and not need furring strips.

Asked By BILL WOLPERT | Mar 13 17
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