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.
Water vapor barrier paint.
If the perm rating of the paint is not indicated on the label find the paint formula.
Vapour barrier paint or vapor barrier paint in the u s.
Moisture vapor barrier primer finish interior latex is a coating designed to reduce the loss of moisture through walls and ceilings.
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.
Water vapor barrier paint is often applied to drywall walls and ceilings in attics where warm air tends to rise.
In the basement water vapor can travel up from the ground and affect the walls and floor in the lower half of your home.
Is more of a solution for walls rather than ceilings to prevent the indoor vapour drive during hot humid weather.
Technically many of these materials are only vapor retarders as they have varying degrees of permeability.
Materials have a moisture vapor transmission rate that is established by standard test methods.
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.
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.
A perm rating is a standard measure of the water vapor permeability of a material.
Basically any material rated at less than 1 perm is considered a vapor barrier retarder.
The paint formula usually indicates the percent of pigment.
Available at distributors nationwide.
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.
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.
In the case of water vapor you will want to consider installing a vapor barrier.
The reason as you may have read is that when there is a vapour barrier in homes in hot humid climates that rely on air conditioning for human comfort that vapour barrier is effectively on the wrong side in the cooling season.
The higher the number the more readily water vapor can diffuse through the material.