Hip and valley rafters must be shortened at the ridge by a horizontal distance equal to ______.

The correct answer is that hip and valley rafters must be shortened at the ridge by a horizontal distance equal to one-half of the 45-degree thickness of the ridge. This measurement is essential to ensure that when the hip and valley rafters meet at the ridge, they fit properly and create a stable roof structure.

The angle of the hip or valley rafters typically approaches 45 degrees, which is crucial for proper load distribution and alignment. By shortening the rafters by this specific measurement, carpenters account for the geometry of the roof, ensuring that the angles and connections are precise. This precision helps to maintain the structural integrity of the roof, as incorrect measurements could lead to misalignment and structural weaknesses.

Understanding these measurements is vital in carpentry because they directly affect how well the rafters will assemble with the rest of the roofing system. This knowledge also enhances the skills required for creating aesthetically pleasing and functional roofing designs.