These are generally difficult to maintain, as they require special materials to avoid leaks.
Generally, these roofs have a pitch from 1/2:12 to 2:12 (from 4.2% to 16.7%).
We can divide roofs into the following categories: For example, a pitch of 1:12 means that for every twelve yards of building length, the rise will be equal to one yard. Roof pitch is often expressed as a ratio between rise and run in the form of x:12. It can be assessed in two ways – either as the angle the rafter makes with the horizontal or the proportion between the rise and the run of the roof. Roof pitch is simply the slope created by the rafter.
