Plastic Vapor Barrier Bathroom Wall

Not every wall does.

Plastic vapor barrier bathroom wall.

Run the height of the vapor barrier from the top all the way down into the shower pan make sure not cut too short before the water barrier. A vapor retarder is a material used to prevent water vapor from diffusing into the wall ceiling or floor during the cold winter. Do not install a vapor barrier over an existing plastic sheeting this will promote condensation. Plastic sheeting is used because of its low level of water permeability.

Install vapor barriers after the bathroom s plumbing electrical and insulation are complete. Plastic specifically 6 mil polyethylene plastic is. They are required beneath your. Vapor barriers sheets of plastic or kraft paper keep water vapor out of the wall cavity so the insulation stays dry.

Use a minimal amount of staples to secure the vapor barrier to the walls studs. Not every type of insulation needs a vapor barrier. It s also a relatively easy option for diyers. Use special sealing tape to join sheets if polyethylene sheets are being used.

Liquid barriers may also be used to prevent moisture from getting into the walls. Illustration by ian worpole. Whether or not you need a vapor retarder hinges on three main factors your climate your home and the location of the wall you re insulating. Moisture barriers stop that water or vapor from getting any farther and potentially rotting your studs the drywall or greenboard installed behind the enclosure.

After the insulation is in place you will want to add a vapor retarder sometimes called a vapor barrier if you need one. Seal all wall cracks and holes in the wall being vapor proofed to block air gaps. Holes in the vapor barrier that allow humid air through may allow a lot more water vapor into an assembly than the vapor barrier is stopping. But if it does the barrier should face inside in northern heating climates and outside in humid southern climates.

A vapor barrier reduces the movement of water vapor by diffusion. Complete air blockage is essential to provide a satisfactory moisture barrier and will also maximize the wall s energy efficiency.