Category Archives: Air Tightness

Foam Insulation Sprayed

Today, Home Energy Partners came out to spray the closed-cell insulation for the slab and exterior walls.

Click here to view the entire Nauhaus Prototype Construction Chronology.

Advantek sheathing and brick mold are installed first to stop the foam and eventually to support the Hemcrete.
Advantek sheathing and brick mold are installed first to stop the foam and eventually to support the Hemcrete.
Brick Mold Installation
Brick Mold Installation
Home Energy Partners Spraying North Wall
Home Energy Partners Spraying North Wall
Home Energy Partners Spraying North Wall
Home Energy Partners Spraying North Wall
Home Energy Partners Spraying Underslab Foam Insulation
Home Energy Partners Spraying Underslab Foam Insulation
Home Energy Partners Spraying Underslab Foam Insulation
Home Energy Partners Spraying Underslab Foam Insulation
Spray Foam Insulation around Ground Loop Stub-out
Spray Foam Insulation around Ground Loop Stub-out
Spray Foam Insulation on CMU
Spray Foam Insulation on CMU

Gravel and Vapor Barrier

Today, another 20 mil. vapor barrier was spread over gravel, in preparation for the insulation and concrete slab.

Click here to view the entire Nauhaus Prototype Construction Chronology.

Drain and Insulation with Gravel
Drain and Insulation with Gravel
Finished Gravel
Finished Gravel

Vapor Barrier at CMU
Vapor Barrier at CMU
All penetrations through the vapor barrier are carefully sealed.
All penetrations through the vapor barrier are carefully sealed.

Finished Vapor Barrier
Finished Vapor Barrier



Slab Edge Insulation and Drain

Today the foam insulation and drain were installed at the edges of the stem walls, and the CMU was sealed.

Click here to view the entire Nauhaus Prototype Construction Chronology.

This insulation will serve as a thermal break for the concrete slab.
This insulation will serve as a thermal break for the concrete slab.

The CMU is sealed to lock out moisture.
The CMU is sealed to lock out moisture.
These ties in the side of the CMU will serve a a mechanical connection to the spray foam insulation.
These ties in the side of the CMU will serve a a mechanical connection to the spray foam insulation.


Vapor Barrier Under Footers

Today a 20 mil. vapor barrier was laid in the trenches.  The concrete footers will be poured on top.   Radon pipes were installed for future venting if necessary, and greywater pipes were stubbed-out in hopes that one day a legal greywater system will be possible.

Click here to view the entire Nauhaus Prototype Construction Chronology.

View of Completed Vapor Barrier from Southwest
View of Completed Vapor Barrier from Southwest

tim vapor barrier
Tim Callahan
Stubbed-out Radon and Greywater Pipes
Stubbed-out Radon and Greywater Pipes

Furnace Free in Vermont

In 1998 Marc Rosenbaum was working on a 22 unit cohousing development in Harland, VT. Amory Lovins told the client that she should build a passive solar house without any backup heat. Marc didn’t buy it, and they went back and forth discussing how it could be done. Then Marc published their correspondence at BuildingGreen.com. It’s definitely worth reading.

:: The Furnace-free House in Vermont

Saul Griffith: Climate Change Recalculated

Saul Griffith is an inventor, and cofounder of Instructables and Makani Power, which is currently developing a high altitude wind generator.

About a year ago he examined how much power was required for each part of his life, and he was surprised at how big his footprint is. In this talk he examines the results and talks about the changes he’s made to reduce his impact.

Saul uploaded his Power Point slides to SlideShare.

Calculate your wattage at WattzOn.com

Soy Based Spray Foam

“I bought some cans of [soy based foam] from home depot. I also bought some “Great Stuff” spray foam. I tested them side by side and the Biobased foam failed. It might have been the cold but it dried dry and crumbly. In comparison the Great Stuff dried like hard chewing gum…

Biobased foam crumbled when touched. This could be because it was cold when we installed it. But Great Stuff was installed exactly at the same time in the same environment…

This is very important because the foam is used to fill cracks. Cracks often expand and contract. The Great Stuff has an elasticity to it that the Biobased does not. Also, I forsee the Biobased foam deteriorating and becoming dust over time.”

There are pictures at the site:  ecobrooklyn.com

Fog Testing for Air Leaks


Energy Design Update Page 7:

One fog-test fan is Marc Rosenbaum, an energy consultant and founder of Energysmiths in Meriden, New Hampshire. “My experience is that if you have a blower-door specification for new construction – so many cfm at 50 pascals – and the test comes in 10 percent more than the specification, the builder will usually ask, ‘Why isn’t that good enough?’ – especially if you are fairly far along in the construction process,” Rosenbaum recently told EDU. “But when you use a fog machine, and you have fog blowing out of a hole in the building, I’ve never had anyone point to it and say, ‘Why isn’t that good enough?’ ”