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Discussion Starter #1 (Edited)
Hello all:
I have hired "some people" to insulate my 20' x 25' crawlspace. The crawlspace is about 3' high, has no moisture barrier, and I seem to remember seeing some ductwork running underneath with no insulation.

They brought the insulation over but I am concerned as it has NO PAPER BACKING and is R19.

I have never heard of insulation with no backer paper. The fact that I have no moisture barrier and they want to install this paperless insulation has raised a red flag.

I would appreciate some advise before they come back. They dropped the insulation off but due to the rainy weather, didn't show up today.

My house was built in 1975 and am not sure when this addition was added but the existing insulation is falling out. My heating bill has been very expensive in spite of installing a new heat pump.

As usual, many thanks for your response.

Donna in Fredericksburg, VA
 

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Asphalt paper-faced fibrous insulation is not required if in Zone 4a or 4b, see sentence above the map; http://www.buildingscience.com/docu...heet-310-vapor-control-layer-recommendations/

A plastic vapor barrier is required per code, on the exposed dirt, 6mill minimum. thickness. Second level of importance is air-sealing the crawl space of all holes from wiring/plumbing, chases, and voids (under tub) where air from crawlspace can mitigate up in to the walls and feed the attic due to a "stack effect"; http://www.wag-aic.org/1999/WAG_99_baker.pdf

If plywood on the floor, it acts similar (permeability) to asphalt kraft paper, slowing the vapor drive. If excessive vents are present or you want better R-value (wind-washing) from the insulation, cover the joist bottoms with housewrap. Remember to weatherstrip/insulate the crawl access door, if in the floor framing.

The premium way is to foamboard the joists, if a wet crawlspace; http://www.buildingscience.com/documents/insights/bsi-009-new-light-in-crawlspaces/

That may require an ignition barrier, check with local AHJ, if you go that way; http://www2.iccsafe.org/cs/committeeArea/pdf_file/RE_06_64_07.pdf

Air-seal with foil tape/mastic+fiber tape and insulate the ducting per minimum code or better as it is supplying the conditioned air to the house. I suggest an "extra" of foamboard the rims against air/moisture, Fig.2: http://www.buildingscience.com/documents/information-sheets/crawlspace-insulation/

Termites; move your cursor over your location on the map; http://www.termites101.org/termite-basics/termites-by-region Stop the ground plastic 1' up the walls for yearly visual termite inspections.

Radon; http://energy.cr.usgs.gov/radon/rnus.html

Gary
 

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Discussion Starter #3
Thank you so much!

Asphalt paper-faced fibrous insulation is not required if in Zone 4a or 4b, see sentence above the map; http://www.buildingscience.com/docu...heet-310-vapor-control-layer-recommendations/

A plastic vapor barrier is required per code, on the exposed dirt, 6mill minimum. thickness. Second level of importance is air-sealing the crawl space of all holes from wiring/plumbing, chases, and voids (under tub) where air from crawlspace can mitigate up in to the walls and feed the attic due to a "stack effect"; http://www.wag-aic.org/1999/WAG_99_baker.pdf

If plywood on the floor, it acts similar (permeability) to asphalt kraft paper, slowing the vapor drive. If excessive vents are present or you want better R-value (wind-washing) from the insulation, cover the joist bottoms with housewrap. Remember to weatherstrip/insulate the crawl access door, if in the floor framing.

The premium way is to foamboard the joists, if a wet crawlspace; http://www.buildingscience.com/documents/insights/bsi-009-new-light-in-crawlspaces/

That may require an ignition barrier, check with local AHJ, if you go that way; http://www2.iccsafe.org/cs/committeeArea/pdf_file/RE_06_64_07.pdf

Air-seal with foil tape/mastic+fiber tape and insulate the ducting per minimum code or better as it is supplying the conditioned air to the house. I suggest an "extra" of foamboard the rims against air/moisture, Fig.2: http://www.buildingscience.com/documents/information-sheets/crawlspace-insulation/

Termites; move your cursor over your location on the map; http://www.termites101.org/termite-basics/termites-by-region Stop the ground plastic 1' up the walls for yearly visual termite inspections.

Radon; http://energy.cr.usgs.gov/radon/rnus.html

Gary
Gary:
Now I'm ready to move :). I just bought my house in Dec '12 and have found so many gottchas (in spite of the home inspection).

How could the addition be built with so much wrong?

Heartfelt thanks for your answer.

Donna in Fredericksburg, VA
 

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Things that we can point out that are wrong. As to the science of building may not be wrong as to the code used at the time. There is code and then there is code or above code. It could have been ok at the time not to insulate or place a vapor barrier on the exposed dirt. Now it is code. Do you understand that now? I sure hope that helps. Listen to Gary he is a well of knowlege.
 
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