How To Insulate An Exterior Wall In A Bathroom

When moisture becomes trapped in walls mold and mildew can grow damaging your home and presenting a potential health danger.

How to insulate an exterior wall in a bathroom.

Bathroom projects need special consideration because of the humidity and moisture that bathrooms generate. Seal the gap between the bottom plate of the wall and the floor with acoustical sealant or caulk. Tuck the insulation into the cavity snug against the top of the stud bay and edges flush with the studs. Handy homeowners can rent an insulation blower.

When you reach the end of the wall cut off the insulation. Use special airtight electrical boxes see photo tip 5 or seal the poly to the electrical box with acoustical sealant. They are painted on surfaces and form a waterproof seal over drywall. Weave loosely to fill the cavity but tightly enough so you won t have to compress the insulation when you install drywall.

Add soundproofing to add soundproofing weave a continuous roll of fiberglass insulation between staggered studs using insulation designed for 2x4 walls. Install vapor barriers after the bathroom s plumbing electrical and insulation are complete. If the whole batt cannot fit inside the cavity cut off the excess material with a scalpel knife leaving a couple of centimeters over on each side to ensure a tight fit. That will reduce its r value.

The batt should not be tightly compressed against the studs. There are two ways to fix this problem. Press the poly into the sealant. For an accurate fit against the bottom of the cavity let the insulation run long then cut it against the bottom plate of the wall framing with your utility knife.

Liquid barriers may also be used to prevent moisture from getting into the walls. Place the insulation slabs or batts inside the wall cavity between the studs.