AT-2481 -- A Technique for Protecting Retrofitted Wood-Frame Walls from Condensation Damage PDF

The stud spaces of a full-scale, wood-frame wall having no conventional vapor barrier were filled with a loose-fill cellulose insulation. A low-permeability paint was applied to the interior surface of one half of the test wall; the other half was untreated. The exterior surface of the test wall was exposed to simulated winter conditions, while the interior surface was exposed to typical indoor conditions.

The effectiveness of the low-permeability paint as a protective measure for preventing moisture accumulation was investigated. The paint was effective in reducing moisture transfer into the treated half of the test wall, thereby reducing the possibility of damaging moisture accumulation. In addition, the effect of accumulated moisture on wall heat transmission was examined.