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15 Answers

Soffit framing after air barrier is complete

I have decided to use a Larsen truss wall detail on a small house that we are building. I was intrigued by an air-sealing detail I heard mentioned, perhaps on this site. The idea was to frame the house and most of the roof but to add the eave and rake overhangs after the building has been made airtight. Does anyone know of a drawing of this sort of detail?

In General questions | Asked By erik olofsson | Jul 10 12
2 Answers

Who provides plans/specs/design help to owner?

I love all the content here. Since I'm designing our new house right now, and trying to pick a builder, I'm near the point that I have to start providing plans/specs. Here's the issue; how do I find the person to draw plans/specify all these complex iissues? Especially concerned with solar PV/mini-split locations, or solar thermal vs heat pump water heater questions. LOcation is Calif zone 11, ie mild winter, hot summer, great solar incidence. So who and how do I find a designer/plan drawer/specifier?

In General questions | Asked By Michael McKinley | Jul 15 12
2 Answers

Heat pumps

What heat pump is best or more cost-effective and most energy-efficient? Direct earth contact or air circulation? Why? Where can I find the best info on these systems? Thanks.

In Mechanicals | Asked By Joe Ross | Jul 15 12
3 Answers

Are retrofit LED lamps for can lights a good alternative for new construction?

Retrofit LED and conventional can will cost about $85 apiece, dedicated LED cans are around $175. What are the advantages/disadvantages?

In Green products and materials | Asked By Terry Herschberger | Jul 15 12
66 Answers

The SunRise Home.

I have been cruising this presentation by Thorsten Chlupp and wanted to see if anyone who might have actualy seen it, might have some comments.
http://passivehouse.us/passiveHouse/2010_Passive_House_Conference_Presen...

In General questions | Asked By Lucas Durand - 7A | Feb 24 11
4 Answers

What is the best way to hold a double studded wall on a >R20 foundation with exterior insulation (ie rigid foam)?

We are aiming toward PassiveHaus standard and plan a double studded wall with dense pack cellulose for the main envelope sitting on top of a foundation preferably with deep exterior insulation (ie 4" rigid foam). The plan would be for the exterior 2x4 (or SIP) to be the roof loading wall (large snow load in northern NH). How do we best insulate the basement/ foundation to allow structural integrity and load and avoid the wall sitting inside of the foundation insulation?

In Green building techniques | Asked By Phil Lawson | Jul 12 12
10 Answers

Rigid Foam in between studs

I live and work in south-central Tennessee and Northern Alabama (Zone 3A). I am working on a wall insulation design for a group of houses that my company will build. We are going to manufacture the walls in our facility before they go to the site. We would like to build a standard stick frame (2x4 studs with sheathing). We would tape every seam on the outside and caulk seams on the inside. Between the studs, we are planning on installing rigid foam board instead of spray foam—we can make a very tight fit because of our jig. On the outside we will add 2” of rigid foam.

In Energy efficiency and durability | Asked By Bradley Bain | Jul 12 12
2 Answers

best way to flash this DEEP innie window....

I am working on a small commercial project, and I am trying to figure out the best way to install and flash this deep innie window. The design intent is to use a clip system vertical wood rainscreen. Since I want a 2' thickness to the wall, I am building 2 walls. An inner 6" metal bearing wall and an outer 2x4 wood wall that holds only the rainscreen. However closing off the gap is what i am trying to figure out. I am using ZIP sheathing with 1.5" XPS foam on the metal framed wall.

In General questions | Asked By Jesse Lizer | Jul 12 12
13 Answers

Exposed rafter tails, GBA CAD detail

I have some elementary (for you) questions that are not elementary to me.

First, the basics: we're going to be building a house in Oregon, Marine Zone 4c. I'm assuming a simple gable roof, shallow 3/12 pitch, California Bungalow style, with the rafter tails showing (no closed soffit). There'll be a raised heel truss, 16" heel to get R-49 in the attic--which will be vented. The walls will be 2x6 (Roxul R-23 mineral wool) with 2" of foam (or Roxul board) and vented rainscreen under 1/2" Nichiha fiber cement siding. Questions:

In General questions | Asked By Gordon Taylor | Jul 11 12
3 Answers

Shrink Wrap

Has anyone tried using shrink wrap under slab or to cover an entire building? I've used it to build temporary structures and cover boats. It's really strong, puncture resistant UV stable and the shrink wrap tape sticks really well. Once heated it conforms to almost any shape. I am thinking about using it under a slab with radiant heat as I have a partial roll lying around. Any thoughts?

In Energy efficiency and durability | Asked By John McCormack | Jul 13 12
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