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11 Answers

Is a capillary break between the footing and foundation wall really necessary?

We are meeting a lot of resistance from local concrete contractors & structural engineers when we tell them that we want a capillary break between the footing and the foundation wall. Are there any documented cases of this capillary action being a source of moisture/ mold / finish material problems? Are there any scientific studies that compare the moisture levels in foundations walls with and without a capillary break? The capillary break makes sense to me intuitively, but nobody wants to pay for it or change their ways unless we can show them proof that it is necessary.

In Green building techniques | Asked By Eric Stear | Jul 31 14
7 Answers

Insulating basement walls of old home in a cold climate

I live in a 1911 home in Duluth, Minnesota (Climate Zone 7A). I have started to insulate my basement walls to R-15 using 3 inches of XPS foam board. Because of the age of the home, our cold climate, and the presence of clay soils, the building inspector recommend that I remove the bottom two feet of insulation in the basement so that the walls are exposed near the basement floor to keep the concrete warm during the winter.

In General questions | Asked By Brad Leick | Aug 31 15
8 Answers

Attic Ductwork

I live in Nashville, TN climate area 4A

My issue is my attic gets so hot in the summer months and my heat pump runs a lot but does not cool very well. This is a duplex home with each side having around 980 sq foot living space.

In Energy efficiency and durability | Asked By Janice West | Jul 11 15
11 Answers

Best strategy for waterproofing and insulating a half block/half brick basement?

I live in a 1920's home in Central Ohio (Climate Zone 5A). The basement has an exposed French drain (ie, the weeping holes, trench, gravel and tile are there, but have not been covered with concrete) with sump pump. The basement is 2/3rds below ground, with the walls made up of half cement block (bottom portion) and half brick and mortar (top portion). The brick and mortar is partially above ground and is covered on the exterior with a stone and mortar veneer.

In Plans Review | Asked By Matt Bierlein | Jul 13 15
1 Answer

Spray foaming around windows

When you spray foam (interior) around a window, is it best to try and not fill the area were the nailing flange hits the WRB? Wouldn't this be true because if the window ever did leak the water would have some place to go? An example is a youtube video I saw were they fully spay foam the four corners with Pur Black - but if water gets in were will it go - it will sit on top of the pur balck - unable to escape.

So it seems to me that I should only spray foam only about half way into the rough opening - thus leaving an escape path for any water intrusion if that were to occur.

In Energy efficiency and durability | Asked By Randy Mason | Sep 1 15
6 Answers

REMOTE walls using Roxul products

I've been on here previously to gauge everyone's thoughts on the building plan for our new house, and I was curious about the opinions out there on what we are currently thinking. We're building in northern Oakland county Michigan climate zone 5. The house is a 2357 sq ft ranch with a walkout basement. We've considered just about everything, but here's where our heads are at the moment:

1) I think we like the idea of doing superior walls for the backfilled foundation walls, with the exposed walls being wood framed (for ease of attaching cladding and framing windows and doors).

In Green building techniques | Asked By Brian W | Aug 30 15
4 Answers

Methods for air sealing the ceiling

Hello,

We are building in a cold climate, zone 7, using ICF walls. Because the walls are ICF, they act as an air barrier, but I'm trying to figure out the best way to air seal the ceiling. Based on what I've read on this site, I'm following a few guidelines:

  • Ceiling will be flat, using energy heel trusses
  • Using blown in cellulose, thinking around R-60
  • No recessed lighting (thanks Martin)
In Green building techniques | Asked By Nick Hall | Aug 28 15
11 Answers

Minisplit or furnace?

Hi, I know there is lots of discussion about this; however, our proposed new construction seems to be in unclear realm of which to use.

In Mechanicals | Asked By Mark Buckingham | Aug 28 15
3 Answers

Wood stove installation and exterior foam board insulation

If I want to install a wood stove through the wall or the roof and both have 6" of foam board on the exterior, are there additional precautions to prevent exhaust heat duct from melting or causing a fire around the insulation? For example, install one or more layers of cement board over the 6" of foam. Then install through the wall or roof duct work.

In Energy efficiency and durability | Asked By HORST SCHMIDT | Jun 30 12
3 Answers

CMU walls and rigid foam

Retrofit concrete block walls painted inside and out. Exterior foam then rainscreen then siding. Keeping painted block as interior walls.
Do I have to be concerned with the vapor permanence of the foam?
Also, would there be any benefit in using foil faced...other than R-value?
Southern Georgia coast.

In GBA Pro help | Asked By Robert Brown | Aug 29 15
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