Install a heavy wire-mesh flue cap on fireplace chimneys. Standard wire-mesh flue caps are available from local hardware stores. Inside attached garages, install wire-mesh screening on the opening where roof rafters meet the top wall place. This is a potential entry point to the attic. If squirrels are especially troublesome, trapping and removal may be necessary.
Squirrels are a protected species.
Check with your local Department of Natural Resources conservation officer regarding the procedures to be followed for the trapping and removal of fur bearing animals. We maintain a page with information about this web server. The University of Minnesota Extension Service is an equal opportunity educator and employer. All rights reserved.