What is the rafter run for a straight gable roof with a span of 36'?

To determine the rafter run for a straight gable roof with a span of 36 feet, it is essential to understand that the span is the total width of the roof from one gable end to the other. Since the gable roof consists of two symmetrical slopes, the rafter run refers to half of the span.

In this case, the span is 36 feet, so the calculation for the rafter run involves dividing the span by two. This gives us:

36 feet (span) ÷ 2 = 18 feet (rafter run).

Thus, the correct answer is 18 feet, which accurately reflects the distance from the ridge of the roof to the point directly above the support wall or plate. Understanding this concept is vital for roof framing and ensuring proper structural stability.