In a stick frame non truss sloped roof these issues usually cause the roof ridge to sag in the middle giving it a swayback look but can also cause one side of the roof to sag.
Roof sagging in middle.
Two or more roofs on one structure spell trouble.
Additionally if your roofer has used material that is much heavier than your previous roof it can sag for the same reason.
A sagging roof can come in one of a few classic forms each with its own cause.
The first step is to always check the beams so that you can determine their condition.
A ridge that droops in the middle forming that unintentional western design feature likely is due to undersized rafters and or missing or inadequate internal bracing rafter or collar ties.
Next assuming that there are no further problems with your timber beams you need to measure the length of the beam.
When the roof framing is assembled two ceiling rafters are often joined together to create a longer span.
If you find an infestation of.
Non foundational reasons for a sagging roof.
Common flaws include undersized rafters insufficient sheathing or too few rafter or collar ties.