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.
How to insulate an exterior wall in a bathroom.
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.
Seal the gap between the bottom plate of the wall and the floor with acoustical sealant or caulk.
Liquid barriers may also be used to prevent moisture from getting into the walls.
When you reach the end of the wall cut off the insulation.
There are two ways to fix this problem.
Weave loosely to fill the cavity but tightly enough so you won t have to compress the insulation when you install drywall.
Press the poly into the sealant.
When moisture becomes trapped in walls mold and mildew can grow damaging your home and presenting a potential health danger.
They are painted on surfaces and form a waterproof seal over 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.
Proper insulation will help keep your bathrooms a comfortable temperature year round.
That will reduce its r value.
Buy unfaced friction fit batts and seal the walls with a 4 mil poly vapor retarder.
The batt should not be tightly compressed against the studs.
Bathroom projects need special consideration because of the humidity and moisture that bathrooms generate.
In an older home there s a good chance that no one insulated the exterior wall before installing the shower.
Use special airtight electrical boxes see photo tip 5 or seal the poly to the electrical box with acoustical sealant.