Today only, HomeDepot.com is offering up to 31% off select insulation. As an idea, you can score this Owens Corning Garage Door Insulation Kit (8-Panels) for just $37.98 (regularly $75.95). Plus, shipping is free or choose free in-store pick up if available near you. This insulation kit is ideal for use on uninsulated metal garage doors and comes with eight fiberglass insulation panels with a durable, washable white vinyl facing. The kit includes enough material to insulate a single car garage door up to 9 feet wide.