Vapour barriers / Guides

Radon and vapour barrier below slab on grade floor
Radon in Homes - Mitigation

Vapour / radon barriers below slab floors

...vapour barrier, we used a 10 mil barrier and a radon evacuation stack to lower radon gas levels in homes, research shows (see below) that thicker membranes offer more effective protection. In this video we are installing a 10 mil vapour barrier but we would probably use a thick vapor barrier like this one in future a...

Vapor retarder latex primer instead of polyethylene sheet
Air and vapour barriers

Replacing polyethylene vapour barriers with latex paint vapor control

...vapour barriers time to understand the difference to air barriers , and firstly it should be pointed out that the water vapour permeating through building materials - the reason for installing a vapour barrier - is not the monster it has been made out to be. 100 times more water vapour is carried though a wall assembly...

Air barriers are essential to a properly functioning wall system
Air and vapour barriers

What is an air barrier?

...barriers 100 times more important than vapour barriers, so why is no one talking about them? We don't talk about air barriers because we are too busy talking about vapor barriers. An air barrier is not something you walk into a building supply store and buy; it is a design concept, and arguably a commitment. Products...

The difference between air barriers and vapour barriers
Air and vapour barriers

The Difference between air barriers and vapor barriers

...barriers and vapor barriers is to prevent moisture from forming at that critical point, they just do it in completely different ways. Vapor barriers The rule for vapor barrier installation in cold climates is to have it on the interior with at least 2/3rds of your insulation on the outside of the vapour barrier. Ai...

Exterior air barrier membrane © Ecohome
Air and vapour barriers

How to install an air barrier for reduced air leakage

...barriers and vapour barriers: The job of a vapour barrier is to prevent vapour diffusion and the job of an air barrier is to stop air leakage through differences in air pressure between inside and out. A wall system should have one vapour barrier, but can have many air barriers. A vapour barrier can act as a very eff...

Interior sheathing as air & vapor barriers in wood frame construction
Air and vapour barriers

Interior sheathing as an air and vapour or vapor barrier

...vapour barrier is determined by the amount of moisture that passes through it, and it is given a rating. Any material that allows less than 60NG (nanograms) of moisture to pass through under specific conditions, is considered a type 9 residential vapour barrier by the National Building Code. Including a vapour contro...

Tyvek home wrap left exposed to wind and UV rays
Air and vapour barriers

Choosing the right house wrap / weather barrier, which is best?

...Vapour impermeable 0.1 perms or less Vapour semi-impermeable 1.0 perm or less and greater than 0.1 perms Vapour semi-permeable 10 perms or less and greater than 1.0 perms Vapour permeable Greater than 10 perms Understanding vapour permeability: All we are talking about so far a...

Choosing between OSB or Plywood for house sheathing for Roofs, Walls & Floors.
Wood and organic materials

Which is better, OSB or Plywood for Roofs, Walls & Floors?

...vapour permeable sheathing membrane. This risk may dictate the use of insulation products with high vapour permeability and low water retention, such as mineral fibre." Where to put vapour barriers (CMHC): "Materials that act as vapour barriers (vapour retarders), including certain types of insulation, must be loca...

Exterior damp proofing and drainage mat to protect basements from wate
Insulation and soundproofing

Best practices for basement insulation in new home construction

...vapour retarder primer ) is recomended as an interior vapour control layer below grade. It is most important to not include a polyethylene vapour barrier or other vapour impermeable materials that prevent walls from drying. 6 mil poly vapour barriers are an above grade solution intended to allow walls to dry to the e...

Finished basements can lead to mold and mildew
Healthy indoor air quality

Why are basements moldy? How to fix or Prevent a Moldy Basement

...barriers on basement insulation will rot your walls " We put vapour barriers in basement wall assemblies to keep moisture from getting into them, as if they didn't already contain thousands of litres of water. Polyethylene won't keep foundations dry, they are already soaking wet. All it will do is prevent the thousan...

Installing foam panel insulation, which is best?
Insulation and soundproofing

Rigid insulation panels: which ones to use for different applications

...vapour barrier. Here is the fun part - Since there is foil on either side of the panel, you end up with a harmless second vapour barrier, which is usually heresy in building design. But this can help in summer months when there is a risk of the vapour drive reversing due to air conditioning during hot humid weather. ...