If squirrels have ever been in your home, It's important to thoroughly remove all squirrel smells. Not only is the smell of squirrel droppings, urine, sweat and body oils unpleasant to many humans, it can also lure other squirrels to the same spot. If new squirrels can smell that other squirrels have been living in the area, they assume it is a safe place to nest. This is a case where, if you want to prevent a recurring problem, you are going to have to do more than spray a little deodorant in the attic.
Locate where the squirrel smell is coming from. Since squirrels are arboreal, or tree-dwelling, when they move into human houses, they often make their homes in attics. Find the room where the squirrel smell is strongest, and check the attic space above that room.
Trap the squirrels, if any are still living there. Use live trap boxes placed at exit holes in the roof to capture the squirrels as they leave to find food. Release them far from your area.
Seal off potential squirrel entrances to the house with stiff metal grating to prevent more squirrels from moving in.
Use an industrial vacuum cleaner to vacuum all squirrel droppings.
Remove squirrel bedding and soiled insulation.
Use a deodorizing product, such as Bac-A-Zap, Odor Hunter or Earth Care Odor Remover Bags. Alternately, use a bowl of vinegar and a bowl of baking soda placed on opposite sides of the space. The baking soda zaps acidic odor molecules, while the vinegar zaps basic odor molecules.
Set out vanilla extract to cover up any remaining smell until the area is fully aired out.