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4 Answers

Foam over Platon dimple mat on foundation

We are stumped at a stage in our building process. Winter is here and we need to deal with our foundation. Our site is dry dry dry, but we are not ready to just attach foam to the cement and backfill without any effort to damp/water proof the foundation.

We are essentially forced to use a mechanical system as the weather and temperatures (-10 degrees celcius and wet) are making any other sort of damp/water proofing impossible (as far as we know).

In Green building techniques | Asked By jessie pratt | Dec 11 12
4 Answers

Best waterproofing to be used over ICF walls

Just put up the ICF walls and filled with concrete on our well insulated house in Zone 7. Was planning on using Grace Bituthene. It seemed to work well on another storage building constructed with the same ICF walls.

The area is properly drain tiled, and the house is in a fairly well drained area to boot.

Just wondering if there is maybe something better out there?



In Energy efficiency and durability | Asked By Steve Lenertz | Jun 29 17
7 Answers

Housewrap under outsulation foam

Can you tell me if the housewrap actually serves a purpose underneath foam board?

In Green building techniques | Asked By Joshua Terry | Aug 3 17
4 Answers

Turning a barn into a house: Roof quandary

Hi GBA community!
I am in the midst of converting a not too old timber framed barn into a house for a friend/client. It's going well, and we have a good plan for the thermal enclosure, in my opinion. There's a small matter of the roof, though.

In Energy efficiency and durability | Asked By David Bailey | Aug 16 17
2 Answers

Average quality built homes needing makeup air because they are airtight

I have a question in regards to homes being built (not necessarily green homes) that are subject to the new energy code with air sealing and blower door tests. These homes are being built with average, code minimum building materials and after a blower door test it is showing the house is tight enough to require make up air.

Seeing as these are not green homes, there was no plan in place ahead of time for a system to bring fresh air into the house. Are you seeing this as a problem in other states as well?

In Energy efficiency and durability | Asked By Brian Ducharme | Aug 17 17
4 Answers

Flat residential roof?

Residential architecture has been leaning towards flat roofs, from what I've seen they always leak!! What is the best way to insulate, and protect from ice & water breaching the asphalt torch down?
Zone 3

In Energy efficiency and durability | Asked By Kris Currie | Aug 17 17
6 Answers

Advice on tight building

I have my house rough framed, we are framing out the roof now. Climate Zone 2 ( Just north of Austin). 2x6 conventional framing 16 on center, and has the typical double headers around windows etc. I am nearing having to lock down my decisions on sheething, insulation etc. I have been considering using Zip R for a couple reasons.

1. breaks my thermal mass, that I have plenty of
2. Weather and air seal.

It is anything but cheap, I am looking probably 7000 for the 1inch.

However I am looking at other options

In Energy efficiency and durability | Asked By Sleaton | Aug 15 17
5 Answers

Interior window shutter/slider

Newbie here. Planning a new house in zone 10-high desert of California. Going with cmu exterior wall with separate 2x4 stud wall. Double wall basicsally, instead of strapping onto cmu for drywall. Thinking of leaving a 1-2" gap between the 2 walls and using that gap to house a sliding/pocket shutter to greatly increase the effective R value if all windows. Haven't seen any good commercially available products and I don't want to Mickey Mouse a diy shutter. Anybody try this? Any insights?


In Green products and materials | Asked By keithtom | Aug 17 17
9 Answers

Interior Rigid Foam on Solid Masonry Walls--Am I Going to be Okay?

I have bought a home with solid masonry walls (CMU block interior wythe, concrete "crick" exterior wythe, plaster on the interior of the wall). I would like to add rigid foam insulation to the interior, with a gypsum board interior finish. The foam would be 1.5" XPS (caulk around sheet perimeter, foam and/or tape between sheets) , then 3/4" furring strips 24"OC, affixed with Tapcons to the block, with 3/4" XPS between the furring strips. Attach drywall to the furring strips.
The home is near Dayton, Oh (extreme southern part of Zone 5).

In Energy efficiency and durability | Asked By Mark Waldron | Aug 15 17
4 Answers

How do I solve a backdraft issue in an airtight house with a three flue chimney?

There is a wood stove in the basement, a fireplace in the living room and a BBQ place in the kitchen. Each has their own flue. When I light a fire in the fireplace, it draws air back into the house through the BBQ flue. If I open a window in the dining room, it stops drawing air down that flue. Unless there is a wind out of the North West, then it is still a problem. Smoke from the chimney flue goes up and out and then gets sucked back in the BBQ flue and comes out in the kitchen.

In GBA Pro help | Asked By Luke Thompson | Jul 30 17
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