Straw — the Perfect Insulator

Insulation is something that traps air and slows the transfer of heat. A bale of straw is an excellent insulator because it is a mass of hollow straws mashed together — air is trapped in between and inside of each straw. Although a bale is dense and feels heavy to pick up, it’s actually 80% air by volume, making it a perfect bundle of insulation that is:

  • Natural
  • Locally available in eastern Ontario
  • Annually renewable
  • Non-toxic
  • A by-product of agriculture
  • Support for local farmers

Straw is often confused for hay because it is also baled, but they are very different. Straw is the stalk that is leftover once the grain, such as wheat, has been harvested. It is typically used for bedding, whereas hay is a mix of dried plants that is fed to livestock. We say, “Hay is for horses and straw is for houses.”

Plaster and straw are a dynamite duo that together form an R-30 super-insulated wall. The plaster protects the bales from wind, moisture, rain, fire and pests, and it solidifies a bale wall’s beautiful shape. Stacking bales, rounding the corners at the openings, and plastering them produces super-insulated walls of unrivaled beauty. No two bale walls are the same, and that character connects people to their homes and makes them feel special. As does the feeling of shelter that comes from thick bale walls that insulate from noise, heat and cold.

There are many different ways of building straw bale walls and since 2004, working on more than 30 projects, Straworks has experienced most of them. In fact, in 2009 we developed the Straworks Wall System No.1 based on our preferred method.