Roxul Vapor Barrier Attic

Vapor barriers installed on the interior side of assemblies impede them from drying toward the interior this is a problem for air conditioned spaces and can be an issue when there is also a vapor impermeable material installed on the assembly s exterior creating a double vapor barrier wall assembly.

Roxul vapor barrier attic.

I am doing a complete renovation of my house right now and i ve chosen to insulate with roxul comfort batts. Roxul batts are made of mineral wool and don t support moisture like say recycled jeans shredded cotton can. I chose to insulate with roxul which has a higher r value than the pink stuff. Whether you are building new or renovating your home use roxul comfortbatt thermal home insulation in your exterior walls attic ceiling and floor frames for top thermal performance.

I ve read that i need to use a vapor barrier but i ve also read that vapor barriers can cause houses to be moldy or can cause rot inside the walls because the walls cannot dry out properly. Most authorities now agree that vapor barriers are important under certain conditions but not necessarily as a whole house solution for every home. With 2 layers between the joists and another layer running perpendicular over top the r value of the insulation in the side attic is in the range of r 40. In some instances the polyethylene when taped and sealed also acts as the air control layer within the assembly.

Note that rock wool insulation only comes un faced meaning there s no kraft paper or foil barrier. Youll see that i mention roxul a lot in that tutorial but roxul is exactly the same as rockwool. I am in zone 4 right on the edge of zone 5 in long island ny. In circumstances where conditions inside a home or office are much different than outdoor conditions water.

Depending on the situation you may need to install an independent permeable membrane to serve as a vapor barrier. A well insulated side attic. Resolution of the vapor barrier debate. And by the way if you re remodeling a shower and use rockwool with kerdi board or wedi s shower system there s no need for a vapor barrier.

For ceilings with sheetrock already and just a crawlspace or attic above it is our understanding from various research that there should be no vapor barrier on top of the roxul batts laid on top of the sheetrocked ceiling. The need for installing a vapor barrier depends on the climate zone of the building. Some debate still occurs over how necessary vapor barriers are but a consensus is growing closer. Product overview roxul comfortbatt r 23 fire resistant thermal home insulation.