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1 Answer

With a masonry exterior home, is "outsulation" the wrong way to go?

I am in the process of building a home in Zone 5, Northeast. The planned exterior is stone and stucco. Ideally I want to maximize the R-value of the wall, upwards of R-30 with an air tight, well sealed wall assembly. As it stands we have a traditional 2x6 wall on the prints. I have looked at various options, ICF, CMU, double 2x4 wall, etc.. Wanting to adhere to the "outsulation" concept, I find it challenging, expensive and questionable hanging a stone veneer wall 2 to 4 inches off the wall to accommodate 1 or 2 layers of taped, stepped rigid insulation.

In Energy efficiency and durability | Asked By Sal Lombardo | Apr 1 14
2 Answers

Shocked and dismayed by PHI Closure!

Not a question... just voicing my sadness at the news of Dr Feist closing the PHI.

It seems that "Wolfgang has left the building" albeit for one that has no interior volume and therefore no heating demand. Below is a quote from the announcement in Building Green. At least there is good news.

"Founding Sphere House Institute
Feist is turning his attention to a new project, he says, involving solid cubes of rigid insulation he has dubbed Sphärhäuser. The Sphärhaus Institut (SHI) promotes three simple metrics for its cubic structures, explained Feist:

0.0 m2 interior space

In PassivHaus | Asked By albert rooks | Apr 1 14
1 Answer

Green or LEED builders in zone 5B (Central Arizona)?

I'm building a home in the central part of Arizona (Sedona) in about a year. I'm currently under contract with a designer who appears to have some comfort and knowledge with Green/LEED design and is excited to design my home around these principals. He is somewhat reluctant, however, to give me names of builders he would recommend. I suspect this is because he doesn't wish to alienate any with whom he regularly works.

Is there a listing of builders in this area that are experienced with Green/LEED building principals?

In PassivHaus | Asked By scott schroeder | Mar 31 14
5 Answers

Question about ductless minisplit heat pumps


I live in a 1275 sq. ft. Cape Cod in southern New Jersey (zone 4A). My house was built in 1980, is two levels, is somewhat well insulated, has an unconditioned but insulated crawl space, has dual-pane Andersen windows (manufactured in the early 1980s), and it has asbestos shingle siding.

In General questions | Asked By Chris Poponak | Mar 30 14
1 Answer

Need impartial help sizing and choosing a brand of minisplit-ductless A/C

Let me thank you in advance for your advice.
We're putting a minisplit ductless system into 3 rooms. 1 compressor and 3 heads.
I've gone to 3 contractors and each has given me different information. 2 of the contractors use Mitsubishi and the third uses Fujitsu. Needless to say they all include heat pumps.

The house is a 1929 stucco structure

1st room is a bedroom on second floor
14'3"x 10'6" x 8' ceiling
exterior wall on one side and one end
18"x 2'9"

Office on third floor (no attic steep pitched roof)
9'9" x 10'8" x 8'10" ceiling

In Mechanicals | Asked By jon keller | Mar 31 14
1 Answer

Substitute for rigid foam on unconditioned attic wall?

I have a simple single story gable roof house with an unconditioned attic. I plan on adding some exterior rigid foam to the walls, but I don't need the foam's insulation value, or any air sealing details, on the gable walls of the attic. I figure I could put tyvek on the sheathing, lap it over the top of the rigid foam of the lower story, and then install some wood spacer blocks on the gable wall that are the same depth as the foam below, and screw the headloks through them when I attach furring strips. This would save me a couple hundred bucks on materials.

In Green building techniques | Asked By Nick Welch | Mar 31 14
0 Answers

New Home

My wife and I are contemplating building a new home. We are planning a small energy-efficient ranch, and are interested in the ideas discussed in the Pretty Good House thread. We live in central New York (near Syracuse), and wonder if anyone would know of either architects/designers or builders near us who have some experience and/or interest in this type of construction. Can answer here or email me at mjm275@cornell.edu.

I am new to this site, and have learned a lot from the material and discussion here. Very helpful!

In Project management | Asked By Michael Miller | Mar 31 14
1 Answer

Roof leak argument for open-cell vs. closed-cell under roof deck

I have heard the same general argument used by several insulation installers (even BPI certified ones). They say that the use of open cell foam affords better leak detection protection and drying to the inside when it sprayed under the roof deck rather than closed cell foam.

GBA seems to favor closed cell based on my reading of the site posts. The house is in Zone 4 and has a standing seam metal roof that is about 6 years old. Any additional thoughts?

In Energy efficiency and durability | Asked By Woody McMahon | Mar 31 14
1 Answer

If a home will run on 100% solar electricity, is it still wise to spend extra $$ to make the home LEED or Passive certified?

If a home I plan to build will run on 100% solar electricity from PV panels on its roof, is it still wise to spend extra $$ to make the home LEED or Passivhaus certified?

The house will be in southern Oregon.

In Energy efficiency and durability | Asked By Eddie Bautista | Mar 30 14
1 Answer

Is AquaPEX safe for drinkable water?

I need to replace existing PVC domestic water pipe with a new pipe.
AquaPEX and polypropylene can be considered.

In Green products and materials | Asked By Andrzej Porwit | Mar 30 14
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