Squirrels Behaving Badly
Repairing rodent-gnawed windowsills
I was preparing to paint my house when I discovered five damaged windowsills. It appears that squirrels have been snacking on them and part of the window frame. How should I go about making repairs?
— Joseph ,Silver Spring, MD
Tom Silva replies: Squirrels aren't after your sills for food. Either they're looking for a place to live, or they're just doing what comes naturally to rodents: gnawing to keep their front teeth from growing too long. Before you start repairs, prune nearby trees to remove any limbs that are serving as their highways to your house.
The best fix for a gnawed sill depends on how bad the damage is. If it isn't too deep or extensive, you can cut out the damaged area, prime it, and fill with a patch of solid wood called a dutchman. (For more on making a
dutchman, see Norm's Notebook, January/February 2003, p. 82.) I'd make it out of cedar, stick it into place with polyurethane glue, then sand it flush. For deeper voids, chisel down to firm wood, coat it with primer, then fill with a squirt from a can of expanding polyurethane foam. When the foam hardens, cut and sand the excess so it's flush with the surrounding surface, then fill any voids with an epoxy wood filler or an auto-body filler. Once the filler is hard, paint the sill. But if the squirrels have eaten away so much wood that patches or fillers aren't practical, you'll have to remove the entire sill and replace it.