What is a vapour barrier / Guides

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

Replacing polyethylene vapour barriers with latex paint vapor control

...vapour is carried though a wall assembly by air leakage, than is carried by vapour diffusion. So the air barrier is 100 times more important than the vapour bar...

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

Interior sheathing as an air and vapour or vapor barrier

...a material qualifies as a vapour barrier is determined by the amount of moisture that passes through it, and it is given a rating. Any material that allows less...

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

What is an air barrier?

...act as air barriers are drywall, sheathing, insulation, house wrap, even the polyethylene we normally install as a vapour barrier can act as an effective air ba...

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

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

...act as an air barrier as well, but the most common installation techniques (staples, nails and hastily installed tape) mean it is a rare case when they actually...

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?

...a material is classified as a type II vapour retarder, which is suitable for use as what is exclusively known as a 'vapour barrier' on a work site, the standard...

Choosing a building envelope
Wall assemblies - new construction

Choosing a building envelope - starting with the perfect wall

...A vapour control layer, or vapor barrier : Although commonly known as a 'vapour barrier' a better term to use would be a vapour retarder. A moisture control b...

Better Basement Design on basement walls prevents mold and midlew
Healthy indoor air quality

Basement renovations: How to prevent mold when finishing basements

...as a high R value per inch, acts as an air barrier and a vapour barrier. However, it has been known to shrink after application, leaving air gaps and a lack of ...

Off grid, passively heated and cooled house in the Gatineau Hills, Que
Off-grid and Net-Zero Housing

Off grid living blog, part 2: passively heated, this house in Quebec aims for LEED certification

...ain heat, and install heavy duty insulation to keep that free heat. Further to that, the house is powered by solar panels, and heated by a woodstove and radia...

Slab-on-grade for Ecohome's upcoming video building guide
Passive solar home design

how to build a slab-on-grade on standard soil

...all assemblies. 6. Radon gas barrier / vapour barrier For added durability over the commonly used 6-mil polyethylene vapour barrier, we used a 10-mil barrie...

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

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

...as a high R value per inch, acts as an air barrier and a vapour barrier. However, it has been known to shrink after application, leaving air gaps and a lack of ...

Building science for LEED v4 wall design made easy
Concept and design

Building science for LEED v4 wall design made easy - video

...as an air and vapour barrier. See our pages on vapour and air movement & the difference between air & vapor barriers to get a better idea of how this works, and...