How much is the double door size?
This question is very general ah?
You have to ask what the size of the double door?
Door size, or door size?
Generally do double door, then the door size standard in the 1 m 6 to 1 m 7 or so, this is the standard!
Door for the 800mm, two words is 1600mm! Plus the thickness of the two borders, and the empty space required for installation
Gap!