Drying characteristics of sprayed cellulose wall cavity insulation

Damp installed cellulose fiber insulation (CFI) leads to a more uniform and homogeneous product having lower density in comparison to dry blown approach, it is self-supporting and does not need permanent retainers, which translates to cost savings for the installer. For these reasons spray-applied CFI has gained more acceptance and popularity in Northern regions of the United States. However, manufacturers provide limited recommendations related to moisture levels within CFI suitable for installing interior finishes and no guidelines on how proper drying rates can be achieved. Laboratory tests were conducted to quantify and validate hygrothermal storage and transport properties of CFI. Computer simulations were performed to examine drying rates and residual moisture content levels. The results indicate slow drying rates for spray-applied CFI installed in cold weather. The drying period for CFI to moisture content levels safe for installing the interior finishes exceeds the recommended 24 to 48 hour period.