Housing researchers look for the best way to keep Interior Alaska walls dry

From The Fairbanks Daily News-Miner, Monday, June 5, 2010:

Everyone in Fairbanks knows summer is when the ground thaws and your bones warm. But it’s also the season when your walls dry by shedding moisture deposited in the wall cavity during the winter. When walls warm in the sun, built-up water vapor wants to go back outside where there’s less moisture.

“The way we build walls controls how much that happens,” said Colin Craven, product testing director at the Cold Climate Housing Research Center. “You want your walls to be able to breathe one way or the other.”

Today, many homeowners add outer foam-board insulation to their houses to save energy, but the extra layer can trap moisture inside the walls, causing mold and decay.

“We always thought, ‘Should we really do this?’ It seems to be working, but there’s no real data besides ‘We haven’t seen houses fall down yet,’” said Terry Duszynski, a Fairbanks energy rater who helped jump start the project.

This summer, the research center is completing a yearlong test of how various wall systems handle moisture in Alaska climates to avoid this type of problem.