# Recalculate Roof Structure

When "Recalculate" is performed on the roof load-bearing structure, all timbers entered in the roof structure are recalculated according to their original rules. The exact values that were used when the members were entered are taken into account during this process.

Example: If a purlin was entered using the horizontal offset in plan and an upper timber and the roof pitch is subsequently changed, the purlin will be adjusted to the new roof pitch using its original input values. The offset in plan remains unchanged and the vertical position of the purlin is altered. Likewise, the slopes of the rafters, ridge rafters and hip/valley rafters are adjusted. If the segments were set perpendicular to the roof surface, these segments will also be adapted to the new roof surface.

For the recalculation no roof surfaces or building outlines are selected as is done for recalculating rafters, because all components are always recalculated.
