Sectional doors are usually constructed of three to eight panels and slide up and overhead. Sectional doors occupy exactly the same amount of internal garage space as a monolithic door.
Sectional doors have two distinct advantages over single panel monolithic doors: Sectional doors do not require any space outside the garage to open. A vehicle may park very close to the garage before opening the door.
Each panel of a sectional door has its own connection to the door track. This increases reliability and robustness compared to monolithic doors, which have only a couple of track connections for the whole panel.
Garage doors can be made out of many materials, but steel, aluminum, wood, copper, glass and vinyl (polyethylene) are the most popular materials. A few manufacturers are making garage doors by putting foamed-in-place polyurethane insulation in monolithic panel and sectional garage doors.