All flashings custom flashing some clarification.
Velux skylight minimum roof pitch.
The roof pitch and the roofing material used are both important in determining the type of flashing needed.
For deck mounted skylights a minimum roof pitch of 3 12 or 14 degrees is required.
Manufacturers therefore recommend a minimum pitch to install their product so that rainwater and debris runs off the glass more effectively keeping the skylight cleaner for longer.
For many skylight applications on flat roofs there should be a minimum pitch or fall of 0 6.
Curb mounted skylights can be installed flat at 0 degrees.