Turning a home inside out may expose the benefits of insulation
American builders have long insulated homes by stuffing the walls with fiberglass or foam. In recent years, building science experts have debated the merits of turning the home inside out by placing a barrier of insulation on the exterior instead.
It’s an unconventional approach, but one that has proven highly beneficial in Europe, where the practice is common and noted for keeping heat from escaping. In fact, heating bills have been known to drop up to 40 percent as a result.
Those who argue against mounting external insulation point to three issues: it’s harder to install, it’s more costly and it’s not up to some fire codes. Another potential concern is that water can get trapped between the insulation and the home wall, leading to mold and mildew buildup.
Building science experts say there are ways to alleviate such concerns by using vapor open insulation, vapor closed insulation or vapor in-between insulation.
“You just design for the materials you want to use,” said John Straube, principal for Building Science Laboratories/Building Science Consulting Inc. “Use only materials that work with a chosen design.”
Those building experts say homeowners concerned about cost will find that added expenses aren’t the result of bad materials, only bad applications. Exterior insulation, done right, brings a host of other benefits – durability, improved overall temperature and moisture conditions in the building cavity.
Companies: Dow Building Solutions
Gary Parsons Gary Parsons is the Lead Building Scientist in Dow Building Solutions Research and Development. He is a LEED Accredited Professional, a licensed residential contractor in the state of Michigan, a member of the Society of Plastics Engineers and a member of ASHRAE. www