This 18x20 carport is the same size as a 18x21 carport sold by other dealers (the dimensions of the roof are actually 18' x 21').The 18x20 vertical roof metal carport comes standard with 6' legs.You can make it taller in 1' increments with up to 16' legs available. Sides can be left open, partially closed or fully closed. You can close one or both gables, close the back or fully enclose it and turn it into a metal garage.Alan's Factory Outlet 18x20 vertical roof carport is 18 wide by 20 long and