What angle is formed by the valley rafter and the main ridge board in a roof with a uniform pitch?

In a roof with a uniform pitch, the angle formed by the valley rafter and the main ridge board is typically 45 degrees. This is because a uniform pitch usually indicates that the roof's slopes on either side of the ridge are equal, leading to the full angle at the ridge being split evenly between the two planes.

When visualizing the layout, the valley rafter acts as a diagonal support that descends from the ridge board down to the eaves, connecting two adjoining roof sections. Since both roof sections incline at equal rates given the uniform pitch, the angle where these two components meet at the ridge board results in a 45-degree angle. This is a standard measurement in roof framing and carpentry, particularly in constructing residential structures where symmetrical design is often employed.