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3 Answers

Housewrap on the gable (non-living attic walls) or not?

My framer will not put Tyvek, house wrap on an gable wall where there is no conditioned air. (non living space above the house. I have found proper attic sealing, venting, insolated articles to back this and to dispute it. Please advise.

In Green building techniques | Asked By william trent | Jul 26 15
2 Answers

Another solar pumping question

Hey there,
I would like to use solar power to pump around 10.000 L of water/day from a well into a reservoir that I could use for gravity fed irrigation via a drip system. Please give me your thoughts on this, I would like to know if it's doable. I'm a newbie so please bare with me if I ask something outrageous
The specs on the pump:
At 45 volts DC the peak efficiency point is 18 GPM at 45 feet of head..
Max Current: 8.5 Amps
Max Power: 380 Watts
My question is:
Is it possible to run this pump directly from solar panels with an LCB? Would 2 x 250W panels wired in series do the job?

In Energy efficiency and durability | Asked By lee alice | Jul 24 15
5 Answers

Kerdi shower system vs. concrete board

Builder recommends the Kerdi shower system applied over the dry wall and that's what the local tile people use too.

One of the bids from an out of town tiler, who works on high ends houses, recommended cement board instead of dry wall?

This is in regards to the shower area in the bathrooms.

Please advice


In General questions | Asked By Yasir Khan | Jul 25 15
4 Answers

Best practice/advice- Three insulation assemblies

I need guidance/advice on insulating three separate assemblies as I finish the space on the 2nd floor of our 1952 Cape Cod.

The space: Total 2nd floor square footage equals 960- all conditioned space
No dormers on the front, single shed dormer spans nearly the entire backside of the house.
Williamsburg VA- Climate Zone 4A- more hot & humid than you might imagine.

Here is what we are starting with:

1. Exterior wall on either end (facing North & South) is constructed as follows- Brick, 1" airspace, #15 felt, 1/2" insulating (asbestos?) sheathing, 2x4 studs

In Energy efficiency and durability | Asked By Chris Kolloff | Jul 24 15
1 Answer

I was interested in Air Krete and wonder how good a product it is to have injected inside my exterior walls from outside

I have a 1960s home without much insulation and at first thought some foam might be good. Now

I hear about Air Krete which claims to be a soft and better injected insulation.

Can I get anyone with experience in using this on an older home or any details about its pros and


Anything about what or whether it is a good material to fill the exterior walls of my home.

Thank you for any information. I don't know anyone to contact.

Tom Mc

In GBA Pro help | Asked By Tom McAuliffe | Jul 24 15
7 Answers

Cut-and-cobble polyiso, then spray foam?

Hello everyone,

In Energy efficiency and durability | Asked By Jason Hood | Jun 28 15
1 Answer

Additional question on rim joist setup

Hi... I recently asked a question about insulating rim joists, and thanks for the response. In my case, because of my brick siding my back side of the house has a setup where there is a small sill within that space, making a bit of an awkward "L" shape enclosure. I have been cutting down polyiso board to 14.5x9" squares to fit a rectangular area but wonder about the space behind it. Is it possible to fill it with fiberglass (with vapor barrier removed) and then the polyiso/foam? It seems relatively water-free but of course air gets in there.

In General questions | Asked By G S | Jul 24 15
7 Answers

Unvented cathedral ceiling assembly for Florida

Hi All,
I've read a lot on this site to learn as much as I can, but I still have some persistent questions about the particulars of my situation.
I've gutted a 325sqft room. It's down to the concrete block walls, slab floor, and existing roof assembly(2x4 rafters, 1x4 decking, felt, metal roof).

In Energy efficiency and durability | Asked By Daniel Alves | Jul 23 15
4 Answers

Insulating interior wall over brick in Phoenix

I have a home in Phoenix built in 1958. All exterior walls are brick and there is exposed brick for interior wall surfaces of those walls.

This is fine, except in one bedroom which gets alot of sun on its two brick walls (the other two walls are interior and are stud/drywall). In summer this bedroom is 5-10° hotter than the rest of the house, and the walls are warm to the touch. I've even tried putting a special vent fan faceplate to move more cold air in there- it only helped slightly.

I'm considering insulating the interior of the two brick walls in this room. Two questions:

In Energy efficiency and durability | Asked By Shawn Us | Jul 23 15
1 Answer

Gray/ grey water system in Southern California

I am new to GBA so bear with me if this has come up before. I am in Southern California with severe drought conditions. I think I have a good arrangement for a greywater system- One story house on a medium slope hillside so my crawl space tapers from 2 ft. to 8 ft. Great for dealing with the utilities. It also might be great for natural drainage of a greywater system. I was wondering if I put a large pool size sand filter inline if I could let the water drain through into a say 100 gallon holding tank and use a submersible pump attached to the drip system and/ or perforated pipe drainage.

In Green building techniques | Asked By Richard Stutsman | Jul 23 15
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