Over time roof rafters can wear crack or rot and replacements may be in order.
Hip roof rafter repair.
This video shows how to repair a split rafter.
Fixing a rafter requires basic carpentry skills and the ability to work in.
Rafter and joist systems are made up of two pieces of wood that run directly beneath the roofing surface and give it its shape while joists bridge the gap between the two rafter ends and support the whole thing.
With the proper tools anyone can do this.
Finally the hip roof may well serve as a mansard at certain angles of inclination of course.