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4 Answers

Re-siding / re-sheathing a 30-year-old double-stud house

I'm in Zone 6. My mother's house was built from the late 70s to the early 80s (not a guess -- it took that long).

Walls are 2x6 and 2x4 staggered studs with pink glass, poly, and sheetrock on the inside, rough-sawn board sheathing, rough-sawn board-and-batten siding. Andersen 2-pane casement low-e windows.

It's time to replace a bunch of siding, as the bottom is rotting where it is close to the deck (rain splashing up in the summer, and constant snow contact in the winter, my guess).

In Energy efficiency and durability | Asked By Trevor Chadwick | Jun 19 16
3 Answers

Solutions for rain screen strapping "sucking in" rigid foam?

During installation of 1X4 strapping (fir) over rigid foam (EPS) with Headlok screws, my builder has been remarking about the Headlok screws tendency to "suck in" and compress the foam.

Anybody have creative solutions for this?

In Green building techniques | Asked By Thomas R | Jun 12 16
9 Answers

Unvented low-slope roof: Do I need a vapor barrier or an air barrier?

I am looking to increase the installation in a bedroom in an early Mid-Century modern home (built 1949).

We are in Zone 3. Roof is low slope 1:12

The house was re-roofed approximately three years ago with a IB Roofing Systems 80 mil PVC membrane in Dark Brown.

I have attached a rough diagram of the roofing layers in this area of the house

In General questions | Asked By Dan Dutcher | Jun 18 16
10 Answers

How can I stop the mold recurring in my wall?

I have a bonus room over my garage with a double window at the gable end. The outside of the wall is brick faced, wrapped in Tyvek over OSB. The inside has fiberglass insulation, and drywall. The house is 12 years old, located in the Midwest.

In GBA Pro help | Asked By Carr Bruton | Jun 18 16
9 Answers

Slab insulation - do I understand the code requirements?

Question about slab insulation. The current slab has zero insulation on each side. That was no issue until now because it always an unheated garage. The slab is just that, a slab. No footing, no drainage.

Living in zone 5A and using the table Martin gave me in another thread I conclude I need:
- R-10 on the edge. --> 2.38" EPS or XPS*
- R-30 on top of the floor indoor. --> 7.14" EPS or XPS*

*= I use R4.2 for both EPS and XPS because I will use reclaimed foam. From what's I've understood XPS outgasses and it's R-value drops to that of EPS over time.

In Building Code Questions | Asked By Tony Tibbar | Jun 18 16
7 Answers

HVAC system sizing

Good day everyone. I'm in the process of building a new custom home in northern NJ. I'm trying to be as energy efficient as possible within budget. It's approximately 5000 Sqft under air, 2.5-story home with a finished basement (included in total sqft calc). I'm trying to properly estimate my HVAC system. The house has R19 insulation on the walls, and R30 in the attic. It has poured concrete foundation. There are 35 (Pella proline) windows in the house, all double-pane, along with 2 glass sliding doors. Exterior walls are 2x6 construction. Front door is R16 rated.

In Energy efficiency and durability | Asked By Eugene Shebayev | Jun 16 16
1 Answer

Enclosing the space under a deck

I have an interesting situation I'm trying to resolve. The home is in southern NY & my client had a deck built about 5 years ago which is fully enclosed below with concrete block walls & stone veneer. The space underneath the deck is unfinished & has at least 8'-9' of headroom & is just used for storage of outdoor furniture in the off season. The space has a few inches of gravel over earth.

In General questions | Asked By Brad DeMotte | Jun 17 16
2 Answers

Am I making a mistake building my house with a sealed attic?

I am building my own home and I want it to last for my son, and be energy efficient. My plan is to build it with a sealed attic with spray foam on the underside of the roof decking. On the top side I want to use a synthetic roof paper covered with a preferred radiant barrier. Then put down 1x4 vertical battens, and then a layer of 2x4 horizontal battens, and finally my metal roof.

In Energy efficiency and durability | Asked By Eric Dawson | Jun 16 16
3 Answers

Frigidaire Mini Split a good deal?

Looking at options for a 12,000 BTU mini split, I find the Firgidaire is about 1/2 the price of a Mitsubishi or Fujitsu. Does the price reflect quality?

In Green products and materials | Asked By David McNeely | Jun 16 16
5 Answers

Does sub-slab insulation need to be secured and where does plastic go when concrete is the finish material?

I am using two 1" layers of reclaimed xps insulation under my slab, and it does not lay really flat. Is there a way to secure it to the gravel layer, and does it need to be? The concrete slab will have radiant heat in it.

In Green building techniques | Asked By Steve Wilson | Jun 16 16
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