Important test - Remember you are measuring aperture sizes, not door sizes.
Largest dimensions ONLY IN WIDTH, smallest dimensions in height. You do not have to allow for the thickness of Spaceslide liners or end panels, our software will automatically reduce the aperture size by the correct amount. Normal overlap on the doors is 35 - 40mm.
However if you are installing your own liners, or installing batons to level up the aperture you must measure the aperture within your installed sections