Weather barrier / Guides

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 ...

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...

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...

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

...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 ’ with 12 ...

Building Climate Zones USA & Canada Maps Help with Specification of Homes
Planning and Design

Climate Zones in USA & Canada for Building Homes events of their specific climates as well. How are climate zones divided in USA & Canada? Using information gathered from 4,775 US weather sites, in the early 2000s, the U.S. Department of Energy’s Pacific Northwest National Laboratory created a simplified map separating North America into 8 general climate...

Blower Door Tests - What's the Cost & Who Does Them?
Air and vapour barriers

What is a blower door test? What's the cost? How do you find a company to do one?

...barriers in the form of 6 mil poly vapor barriers , exterior weather resistant barriers (WRBs) , tapes and caulking etc, so the cost doesn’t really go up much. All you need to do to improve the air seal is take your time and be a bit more careful, and what’s the point of taping the joints of a membrane if you don’t do ...

Passive home designer Harold Orr, one of the original high performance homes
Passive solar home design

The principal designer of the house that inspired the global Passivhaus movement reflects on the project that started it all.

...barrier was installed on the inner surface of the inner wall. This meant that all electrical boxes had to be sealed to the air / vapour barrier and the barrier had to be carefully sealed where interior partitions and the second floor joists passed through it. In 1977, there were no contractors with experience or trai...

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?

...barriers (CMHC): "Materials that act as vapour barriers (vapour retarders), including certain types of insulation, must be located within the assembly so that moisture moving from the inside to the outside does not condense and accumulate within the assembly. This means that vapour barriers should be located on the w...

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

Rigid insulation panels: which ones to use for different applications

...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. Any inw...

Crawlspace radon barrier installation for radon mitigation
Radon in Homes - Mitigation

Removing radon gas from basements and crawlspaces

...barrier needs to be installed to seal off the ground from the air in the crawlspace . A DIY radon mitigation solution for a crawlspace is to use a standard 6 mil polyethylene vapour barrier, which works, but contractors may be required by law to use a fire-rated membrane. The membrane itself is not impermeable to radon...

Pre-fabricated straw bale SIPS panels, an environmental choice
Wall assemblies - new construction

Modern straw bale SIPS construction: high performance, durable, affordable & interesting during construction, and the quick installation of finished panels means you can get a roof over them quickly. When I spoke with Chris Magwood about the public perception regarding moisture issues, he had this to say: " We think nothing about putting trees in our walls; straw is the same organic material. It'...