Told By Whom? lol

[homebild]

The information I have given is correct according to established building codes.

No vapor barriers are required when the wall or ceiling assembly vents to the outside and no vapor barriers are required when spray on foam is used because it prevents the surface temperatures from ever falling below the dew pont, therefore no condensation occurs.

International residential Code 2003:

“R318.1 Moisture Control. In all framed walls, floors and roof/ceilings comprising elements of the the building thermal envelope, a vapor retarder shall be installed on the warm-in-winter side of the insulation.

Exceptions:

1. In construction where moisture or freezing will not damage the materials.

2. Where the framed cavity or space is ventilated to allow moisture to escape.

3. In counties identified with footnote a in table N1101.2″

In this case, no vapor barrier is required for an attic space that is ventilated to the outside AND because the spray insulation type prevents condensation from occuring to even damage the materials.