Insulation For Basement Walls Vapor Barrier

The water vapor can come through the concrete from the soil or from indoor air that comes in contact with the concrete.

Insulation for basement walls vapor barrier.

This will give you two vapor barriers one before and one after the stud wall framing. A vapor retarder is a material used to prevent water vapor from diffusing into the wall ceiling or floor during the cold winter. The construction of the wall for instance is vital to the use of a vapor barrier. Also on the graph is the permeance of polyethylene.

With fiber insulation and a vapor barrier moisture can get trapped in the insulation leading to moldy insulation and decay in the wood framing. Not every wall does. 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. Whether your vapor barrier is a facing or a film it must be placed on the warm in winter side of the wall.

Not so asphalt saturated kraft paper. Not to be confused with a vapor barrier which is placed on the warm side of the wall just in front of the insulation and behind the drywall a moisture barrier goes against the basement wall and. This barrier is meant to keep moisture from getting to the insulation in the walls and ceilings and it is required by building codes when insulating most houses. You should then use fiberglass insulation that has a vapor barrier between the studs with the vapor barrier facing in toward the living space.

As the wall dries the water vapor leaves the concrete and tries to penetrate the insulation and wall. The vapor barrier is sealed to the concrete wall at the bottom with some sort of seal and nailed directly to the concrete. 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. Basement insulation vapor barriers the trick with basement insulation jobs is in understanding where water vapor is being stored and where it s moving to.

And most walls with asphalt saturated kraft paper thank the building science gods for the difference. If you live in a hot humid climate place the vapor barrier toward the outside of the wall cavity. Concrete is like a huge sponge which holds water and water vapor for years and years. If you live in a cold climate place the vapor barrier between the interior of your home and the insulation.

After the insulation is in place you will want to add a vapor retarder sometimes called a vapor barrier if you need one. Joe says in the article plastic vapor barriers really are vapor barriers when things get wet. In any case the vapor barrier must point to the warm side. Of foam against the wall this should not be a problem in your climate.