Vapor Barrier On Concrete Walls In Basement

If you have a framed wall that is adjacent to a concrete foundation wall where the vapor barrier is next to the drywall in front of the studs the fiberglass insulation gets wet and becomes a breeding ground for mold.

Vapor barrier on concrete walls in basement.

Building codes usually require a vapor barrier 4 mil plastic sheeting on exterior basement walls if the framing is attached to masonry or concrete surfaces or if the wood framing butts up against the outer basement walls. With fiber insulation and a vapor barrier moisture can get trapped in the insulation leading to moldy insulation and decay in the wood framing. When the mold grows it will spread to everything around it studs drywall etc. A vapor barrier is also helpful to keeping a basement insulated and warm.

That is if the studs are going to touch the concrete wall. It s not rocket science. The water vapor can come through the concrete from the soil or from indoor air that comes in contact with the concrete. You should then use fiberglass insulation that has a vapor barrier between the studs with the vapor barrier facing in toward the living space.

For a basement that vapor barrier should be the waterproof membrane or coating on the outside of the concrete wall. Polyurethane sheeting is a typical vapor barrier that contractors use to prevent moisture from penetrating the walls of a basement. The construction of the wall for instance is vital to the use of a vapor barrier. No vb is perfect.

If you ve ever had a problem with a basement floor or any concrete floor you know the kind of damage that too much moisture can cause. So there is enough gap for air to flow. Or you can leave a 4 inch gap between the studs and concrete wall and probably get away with it. Ok people for the 957th time.

Vapor barriers are used because while fresh concrete is poured wet it s not supposed to stay that way. The material is stapled to the frame of a basement wall before it is finished with plaster or drywall. Of foam against the wall this should not be a problem in your climate. Most jurisdictions require a 4 mil plastic sheet vapor barrier for basement walls against concrete.

Vapor barrier against basement walls on september 8 2020 by amik basement waterproofing wall vapor if our sauna walls could talk insulate basement finishing how to finish mold growth under fibergl insulation basement insulation retrofits fine. Only one vapor barrier maximum in the wall.