Pitch:

It is the ratio of the rise to the span of the truss, therefore

Pitch = Rise/Span

The roof pitch depends upon the rain or snow which falls on the roof and has to be drained off. A pitch is steeper in areas of greater rainfall or where snowfall takes place. That also depends upon the nature of roof cladding used (Table 1).

Slope

Slope of the roof is the angle which the inclined roof surface makes with the horizontal and may be expressed in terms of degrees or as 1 vertical to x horizontal (1 V : x H). Thus, value of slope is numerically twice that of pitch.

Slope = 2 (Rise) /Span

Table : Pitch of Roof