Can mice chew through foam sealant?

Yes, mice can chew through foam sealant, including spray foam insulation and Great Stuff gap filler, as foam is soft and not rodent-proof, similar to how pests can damage soft storage materials. Mice have strong teeth that can gnaw through many materials, and expanding foam sealant, both open and closed cell, is easy for them to chew, so foam alone does not stop mice entry. While foam seals air gaps, mice can chew new hole through it within days if motivated by food or warmth, so foam sealant not considered rodent proof. To prevent mice chewing through foam, use rodent-proof methods like combining foam with steel wool, copper mesh, or hardware cloth embedded in foam, or use cement or metal flashing for larger holes. Some foam products claim pest block with bitter additive, but mice can still chew if determined. So yes, mice can chew through foam sealant easily, so for rodent exclusion, do not rely on foam alone, use foam as air seal plus mechanical barrier like steel wool, copper mesh, or metal, and address food sources and entry points, similar to securing storage from pests.