Can I use a magnetic air seal on an exterior door?
Magnetic weatherstripping for doors is quite common. It attaches around the door in a grove that's part of the door trim. Inside the gasket is a magnet that pulls it tight to the door to form an airtight seal.



That is a cross section view. The fishbone shape on the bottom goes into the door trim for a tight seal. The magnet is the dark part on top and is inside of the weatherstripping so that it pulls the vinyl or rubber tight against the door. Click through the photo for a sample Amazon product.