Although it would take the squirrel awhile to actually get through the brick chewing on it, they could eventually create hole in bricks and get through that hold.
One way to stop squirrels is by putting a piece of steel over where the squirrel is entering places they're not supposed too.
A squirrel cannot chew through a piece of thick metal. Although a squirrel can chew through thin wire mesh bot not a thick steel mesh or thick steel plate.