For an experienced builder, installing layers like house wrap, polyethylene vapour barrier or air barrier material is a quick exercise in rolling out flat, caulking, stapling and taping.

But with this speed of installation comes opportunity for thousands of tiny little holes that allow air to flow into your structural and thermal assemblies. Not to mention that poorly taped up section, or the part that was folded and stretched too much.

The AIR BARRIER in Passive House construction must be carefully installed and isolated from accidental cuts and tears as the build continues. This layer is one of the most critical for achieving Passive House performance of 0.6 ACH @ 50 Pa.

How do you do it?

• Use durable, high quality materials for your air barrier, adhesives, tapes and gaskets. Here's a great place to look for High Performance Building Supplies.
• Talk to your workers about careful installation and care for the air barrier. The air barrier can NOT be perforated and the site super should know about any accidents.
• Keep your site clean and neat so the installation goes smoothly. Vacuum up any dust and remove any sharp points in the assembly area before installing.
• Follow the staple and adhesive pattern recommended by the product manufacturer. Put away that hammer tacker!
• Protect your air barrier by carefully planning penetrations for utilities and using separated interior framed cavities for plumbing and electrical work.

The air barrier must be continuous around the entire building envelope, including windows, doors, slab, walls and ceilings. If you can draw an unbroken line of air barrier around the shape of your building, you're on the right track.