The rolled roofing should reach the chalk line when you lay it down and should stretch from 1 side of the roof to the other.
How to lay roll roofing on a flat roof.
Place the top edge of the roofing along the chalk line.
Roll out and cut roll roofing to cover the length of the roof.
Working with a helper expect to spend half a day installing flashings and roll roofing for a 700 square foot roof with modest complications.
Prepare the roof by tearing off the old shingles or by preparing for a reroof.
Typically a flat roof is a low sloping roof with a maximum 10 degrees of pitch or usually having a slope of up to 3 inches per linear foot for adequate drainage.
For a flat or nearly flat roof use double coverage although a torch down modified bitumen or epdm roof is a better solution.
Installing peel and stick roll roofing on a flat roof requires a minimum slope of 1 2 inch per 12 inch roof run.
You ll need to use plenty of pressure with the razor knife to cut the rolled roofing material.
How to install roll roofing on a flat or pitched roof with your own hands.