Attic Kraft Paper

Kraft paper the asphalt impregnated brown paper facing available on insulation is rarely called for these days.

Attic kraft paper. According to owens corning and certainteed makers of insulation kraft paper is a retarder not a barrier. Whether it is made from paper or plastic it always faces whichever space is typically warmest in winter. Do the air sealing. Attic insulation is available with and without a paper facing.

Some builders rely on batts with attached kraft paper facing to do that job but tom recommends unfaced batts covered in plastic with all the seams taped shut. As the kraft paper tabs on the existing insulation are stapled i inevitably ended up with a lot of tears around light junction boxes top plates etc. Kraft faced insulation includes a paper vapor retarder which helps prevent mold and mildew. The paper creates a vapor barrier that helps keep the water vapor in the warm moist heated indoor air from migrating outward into the wall or other structure.

When insulation was first developed it was only an inch or two thick and the attached kraft facing was stapled to studs to keep it from sagging. The house was built in 1967 so i had to pull up the existing insulation in order to air seal. Kraft faced insulation should be installed in exterior walls exterior basement walls and attic ceilings by pressing the product into the wall cavity with the paper side facing outward towards the installer. Paper faced insulation means that one side of the insulation material comes lined with paper.

This is usually kraft paper but sometimes other types of paper can be used. The facing on kraft faced insulation is made of kraft paper with an asphalt coating that makes the paper impermeable to water vapor. Batts in the rafters simply jamming batts between the rafters of a cathedral ceiling or insulated attic will interfere with the roof s ability to breathe. Stop worrying so much about vapor retarders.

First the kraft paper is a vapor retarder meant to reduce the potential for moisture problems caused by diffusion. It has to do with the way it is processed. The vapor retarder kraft paper is facing toward the conditioned side. The facing contains a thin layer of asphalt which acts as a vapor barrier to block moisture.

Sounds like a good idea but the vast majority of moisture problems are caused by air leakage not diffusion even in places like maine. Insulating attic floors unfinished or uninsulated attics need a layer of protection. They also state that the vapor retarder is a one way ticket to allow moisture out of the structure but not back in.