If there is no vent in the vicinity, check the band joists and, if they are not fully insulated, please do so by placing R-19 fiberglass or Roxul insulation tightly against the band joists throughout the crawl space and staple a plastic vapor retarder
to the floor sheathing, the sides of the joists and the mud sill in each space to protect the insulation from moisture migration.
The code language states "in Climate Zones 5, 6, 7 and 8 any air-impermeable insulation shall be a Class II vapor retarder
now offers Wall Guardian FW-100A, a liquid-applied fibered acrylic air barrier that also acts as a water/weather barrier and vapor retarder
Later he joined the JM Roofing Division, where he received a patent for a fire-rated vapor retarder
system and co-developed other patented products.
The plywood that is likely to be the subfloor under the hardwood floor is an effective vapor retarder
and all you need.
From the exterior to the interior, the studied wood-framed wall, shown in Figure 3, is comprised of cement based plaster, a layer of wall membrane, oriented strand board (OSB), cellulose fiber, a layer of vapor retarder
and gypsum board.
One common insulation system is a layer of fiberglass insulation laminated to a water vapor retarder
that is pulled across the top of the purlins (or outside of the girts)--conventionally referred to as "over-the-purlin" or "over-the-girt" (OP or OG) systems (also, "single layer" systems) within Standard 90.
We recommend filling the stud spaces with friction-fit fiberglass batts, covering the walls and ceiling with a 4-mil poly vapor retarder
, and blowing insulation (cellulose insulation is a good choice) into the attic after the ceiling drywall is installed.
To preserve the vapor retarder
while housing the building's heating, power and communications distribution systems, an interior utility chase is provided within the exterior walls.
The change allows unvented roof assemblies if two conditions are met: there's no vapor retarder
between the attic and the home's living space, and the builder insulates between the rafters with air-impermeable insulation.
The analyses even returned one situation where the vapor barrier needed to be a vapor retarder
Should the vapor retarder
be placed next to or external to the insulation?