The higher the number the more readily water vapor can diffuse through the material.
Water vapor barrier paint.
The paint formula usually indicates the percent of pigment.
Fluid applied air water resistive barrier and water vapor barrier vb is a fluid applied air and water resistive barrier that stops air and water leakage in cavity wall masonry veneer construction as well as in stucco eifs and most other building wall assemblies.
Water vapor barrier paint is often applied to drywall walls and ceilings in attics where warm air tends to rise.
Basically any material rated at less than 1 perm is considered a vapor barrier retarder.
The company zinsser makes a shellac based white primer called bin that is primarially used for hiding difficult stains but it too rates in at less than 1 perm and this company depending who is working in their labeling department this month occasionally identifies it as a vapour barrier paint.
Materials have a moisture vapor transmission rate that is established by standard test methods.
Available at distributors nationwide.
A perm rating is a standard measure of the water vapor permeability of a material.
If the perm rating of the paint is not indicated on the label find the paint formula.
One common set of units is g m day or g.
Vapour barrier paint or vapor barrier paint in the u s.
Hydrohalt s water based polymer modified formula waterproofs and prevents vapor transmission for a variety of subterranean surfaces including concrete masonry brick block wood and metal.
Moisture vapor barrier primer finish interior latex is a coating designed to reduce the loss of moisture through walls and ceilings.
Technically many of these materials are only vapor retarders as they have varying degrees of permeability.
Basement vapor barrier paint is a modern development for water barrier techniques.
Vapor barrier paints can be an effective option for existing homes in colder climates.
It combines a primer and finish in a single fast drying coat and is specially formulated for manufactured housing facilities.
Is more of a solution for walls rather than ceilings to prevent the indoor vapour drive during hot humid weather.
Without water vapor barrier paint the warm air would release its water inside of the walls and ceilings where the water would saturate the insulation and framing.
A vapor barrier is any material used for damp proofing typically a plastic or foil sheet that resists diffusion of moisture through the wall floor ceiling or roof assemblies of buildings to prevent interstitial condensation and of packaging.
In the basement water vapor can travel up from the ground and affect the walls and floor in the lower half of your home.