Rafters are the sloping beams that support the load of the roof. They have been around since day one.

This tool handles common rafters, lean to's, hip roofs, and more!

Beside being a basic survival requirement for people, they can also be arranged into complicated forms of art.

Either way, the concept is the same:

Erect the framing members in a safe and easy manner which is precise to the blueprints or other drawings.

The cuts should fit as precisely as possible using standard framing tools and material.

The process starts with the overall roof width.

From here, the thickness of the ridge is subtracted and the remainder is divided by two by the calculator.

Then, according to the pitch of the roof, the rise rise is determined by the calculator so that scaffolding may be erected.

The most important part of the calculation is done based on the Pythagorean Theorem. It is fail-safe and highly accurate to infinity.