Vapor barrier / Guides

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

Interior sheathing as an air and vapour or vapor barrier

...barrier and vapour barrier, and eliminating the need to install a separate product to do that job. One of the benefits of OSB as an air barrier is that it is solid. A polyethylene or foil air barrier can be easily pierced by the slightest touch with a sharp tool, without even realizing it. In contrast, it is unlikely...

Poly vapour barriers in air conditioned houses can cause mold and rot
Healthy indoor air quality

Why you should Never Install Air-Con in a Home with a Vapor Barrier

...Vapor Barrier + Air-Con = Damp Moldy Walls So here's a little known fact that most HVAC installers won't tell a potential new client for central air; Polyethylene vapor barriers in combination with air conditioning in homes can rot walls because of the condensation they may cause. This is why if you have a newer home...

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

Replacing polyethylene vapour barriers with latex paint vapor control

...vapor semi-permeable interior finishes. The following main principles are recommended: Avoid vapor barriers where vapor retarders will work, avoid vapor retarders where vapor permeable materials will work. Avoid the installation of a vapor barrier on both sides of the wall assembly. Avoid using poly, foil fac...

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

The Difference between air barriers and vapor barriers

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

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

What is an air barrier?

...vapor is carried into our walls by air leakage than is carried by vapor diffusion. That makes air 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...

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

Vapour / radon barriers below slab floors

...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 as the c...

Passive House wall system ; Larsen Trusses & dense-packed cellulose insulation
Wall assemblies - new construction

Larsen truss wall systems with double-stud construction & extra insulation for new homes & energy efficient home renovation

...vapor barrier and air barrier 11 7/8" TGIs (I-joists) as a double-stud wall attached to the exterior of the sheathing (R42) 1.5" ECO4 Wood fiber-board rigid exterior insulation (R4) Weather barrier (WRB) Strapping Exterior cladding * Both homes are built on a raft-slab ‘ slab on grade ICF Forming kit ’ wi...

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

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

...barriers and rainscreens play in a wall, choosing the right products and installation tips for optimum performance. They're officially known as water-resistive barriers or WRBs, sometimes weather-resistive barriers, but in practical terms they are more commonly called housewraps and weather barriers. With so many opt...

How to Insulate Exterior Walls from the Outside US Canada Ecohome
Walls and Roofs

The easiest way to insulate walls from the exterior in older homes

...vapor retarder or vapor barrier, it’s important not to add another vapor-impermeable layer on the opposite side of the wall that could trap moisture in the middle along with organic materials such as insulation or wood framing members. Some rigid insulation boards have integrated air barriers, some have vapor barrier...

Frost in Attics: What causes Attic Ice? How to Fix it?
Roof assemblies - renovation

Why is there frost in my attic? Is ice in roofs a problem & How do I stop it?

...vaporate so that the wood can dry. However, it becomes a more serious problem when the quantity of frost isn't able to evaporate before more starts to accumulate. The longer this goes on, the greater volume of ice you will have building up and the greater volume of water you may have leaking down into the ceiling and...

Celsius Solar Igloo
Solar thermal collectors

Celsius: The solar heated igloo!

...vapor barrier (interior) and the air barrier (exterior). Us: How is the sun used to heat and power the igloo? L. McC : Recessed in the south wall are solar air heating panels that capture the heat of the sun during the day and store it in the thermal mass bench which then radiates heat at night. On the roof are photovo...