There are two main types of garage door insulation available. Polyester and polystyrene. We prefer to use a polyester product over a polystyrene product for one main reason. Polyester is a semi rigid malleable board which means all areas of the door can be completely insulated by tucking the product right in behind the metal uprights on the door. Polystyrene is a totally rigid board which cannot be bent or moved; therefore it leaves gaps in behind the uprights on the door cavity.
Because of polyester's malleable properties, it makes it far more effective than rigid polystyrene. The polyester creates a complete seal over the whole surface area of the door. Read our full "Retrofit Your Garage Door With Insulation" blog here.