Comments on: A Fun Visualization of Air Leakage During a Blower Door Test

By: Ecohome insulation

Ecohome insulation — Mon, 16 Jul 2012 02:27:47 +0000

Very interesting, I have not
Very interesting, I have not seen this captured on camera before. Thanks

By: Ecohome insulation

Ecohome insulation — Mon, 16 Jul 2012 02:27:38 +0000

Very interesting, I have not
Very interesting, I have not seen this captured on camera before. Thanks

By: Gene Wilhoit

Gene Wilhoit — Sun, 10 Jun 2012 00:55:43 +0000

Allison,

Allison,

I had a problem getting the ACH down in a two story home on a crawl space that had carpet and wood in the kitchen on a weatherization project.

The plastic billowed up like the picture.

We had rim joists issues on the second floor system.

After 27 years of running framing crews and understanding if you run 48 inches of subfloor adhesive at each run of plywood and use your 2x4 bumper stick to drive the t&g; closed, you will quickly get adhesive all over your bumper stick and your hands every time you pick it up and move it to the next piece. the solution to this problem is to run a 40 to 44 inch run of adhesive and it will not squirt out from under the plywood when you lay it, or get glue all over your hands.

There is a tremendous amount of air moving through the t&g; of each piece of plywood under the carpet.

Crawl space or floor system encapsulation is about the only way to cure it that I could figure out.

Any ideas?

Thanks,

Gene Wilhoit

By: John Ring

John Ring — Sat, 09 Jun 2012 23:54:07 +0000
David,

David,
Look closely at the picture, the plastic that is not lifting seems to be a perimeter lay-down of the sticky-backed plastic used for protecting stairs and walk paths.. The lifting center is simply a piece of standard plastic. I believe that accounts for what we see and does not indicate segmented pressurization.
John

By: David Fay

David Fay — Sat, 09 Jun 2012 01:15:30 +0000
What's odd is that the
What's odd is that the plastic balloons only in one section of the floor. Does this mean that there is a hole in the floor/carpet under that section of the floor that connects to outside? Or could pressurized air be trapped only in that section of the floor? If the latter, ballooning means only that the room is depressurized relative to the trapped air, not that there is a leak in the building envelope.

David

By: M. Johnson

M. Johnson — Sat, 09 Jun 2012 00:27:03 +0000
The above comment makes a
The above comment makes a good observation about master bedroom suites without a return. My own airflow was measured at 1450 CFM total, of which 680 CFM was behind the bedroom door without any return provision in the original house. I made sure there was a return path added.

By: Debbie

Debbie — Fri, 08 Jun 2012 21:56:48 +0000
sole plate of walls not
sole plate of walls not sealed to subfloor.

air leaks under sole plate. to caulk or use sill seal stops this leakage.

in homes on slabs the sheetrock leaves dust trails on hardwood or ceramic tile floors. if carpet then the air is filtered thru carpet.

when hvac folk talk about ghosting from candles it is this leakage site (sole plate) and the room going negative. not candles. dirt is filtered thru carpet leaving dirt trail usually due to lack of return air. usually master bedroom suites with 2 supplies in bedroom, supplies in closets and master bath. door undercut 1" is insufficient for return of 5+ supplies.

By: Thomas Anreise

Thomas Anreise — Fri, 08 Jun 2012 20:49:20 +0000
This is also a great one to
This is also a great one to show homeowners who paid a little extra for the "100%" glue-down option on their new kitchen vinyl.

By: John Semmelhack

John Semmelhack — Fri, 08 Jun 2012 20:29:24 +0000
This is always fun to show
This is always fun to show off to the owner/builder. I had a cool one recently with an impeccably installed crawlspace vapor barrier. The VB lifted up about 18 inches off the dirt, but virtually no air was getting through.

By: Andrew Herren

Andrew Herren — Fri, 08 Jun 2012 19:42:24 +0000
This happened in most every
This happened in most every mobile home I monitored in the WX Program. I stopped the test may times for fear that the vinyl would be damaged! I was never really sure where this was coming from in a doublewide...the center seam between the two halves maybe?