In designing exterior wall systems moisture infiltration is controlled following two basic design concepts or strategies.
Moisture barrier for exterior concrete walls.
Finished basements often receive a vapor barrier layer between the concrete and the floor treatment to prevent damage from heavy rains or other moisture seepage.
Very hot and humid climates may benefit from an exterior vapor barrier that keeps outside humidity from penetrating into walls.
Either design strategy can be applied to load bearing or non load bearing walls.
But the odds are it will be a constant flux of condense and reabsorption back into the.
Before framing the walls of your basement install a moisture barrier to prevent water and moisture from entering the wall cavity.
The other option is to set the 2 4 wall framing in 4 from the masonry or concrete basement walls and use just the vapor barrier on the insulation facing toward the living space.
A vapor barrier against the concrete surface is generally recommended before wood framing or flooring materials are installed.
Or similar moisture and air barrier on top of.
Vapor barriers are applied to the interior walls in climates which are predominantly cold while they are best applied to exterior wells in predominantly hot climates.
Also be sure to use treated lumber for the bottom plate on the wall framing.
Well as the joint between the foundation and the exterior of the wall assembly.
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.
After the insulation is in place you will want to add a vapor retarder sometimes called a vapor barrier if you need one.
A vapor retarder is a material used to prevent water vapor from diffusing into the wall ceiling or floor during the cold winter.
In any case the vapor barrier must point to the warm side.
Not every wall does.
The first design concept is the barrier system where all moisture is resisted by the exterior surface material also often.
Vapor barriers are sheets of plastic or other material placed on one side of insulation sheets.
Whether or not you need a vapor retarder hinges on three main factors.
Or some how or another insulate the exterior of slab that is exposed to the crawlspace to keep that moisture from wanting to stick to the cool wall of slab.
A concrete vapor barrier is any material that prevents moisture from entering a concrete slab.
The standard installation of a plastic vapor barrier is between the studs and the drywall but there are some exceptions to this.
Here are three different types explained.