Length of your roof
(include overhangs)
Width of your roof
(include overhangs)
x
Square feet of your roof =
Slope factor
(see chart)
x
TOTAL
=
Add 10% for gable roofs,
17% on cottage roofs for
hips, ridges and waste +
TOTAL
=
100
/
Number of squares
needed
=
Add shingles required for
starter (total length of
eave divided by length
of shingle) +
TOTAL
=