The Rafter Square, or Speed Square, does more than mark perpendicular lines. Here's how to make sense of all the numbers on your square and get the most out of this tool.

Johnson Johnny Square Mach-1 Takes Layout Tools to the Next Level When it comes to precision in framing and carpentry, […] ...

and layout of virtually any rafter configuration. The book is a fantastic resource, especially if you don't use a Speed Square every day. While some folks find all the markings on the Speed Square ...

For L.B. of Whitehall, it's a a triangular-shaped measuring tool used to mark straight lines and virtually any angle in construction work. One popular brand is Speed Square. like on rafters.