Abstract: A framing square for marking transverse, gable, hip/valley cut lines on a large standard sheathing panel includes an elongated rectangular scale with a transverse T-bar handle of equal width having transverse guide surfaces terminating a pivot point at the lateral ends thereof. The scale includes a first set of pitch angle lines for establishing gable cuts extending across the width of the panel and a second set of pitch angle lines for establishing hip/valley cuts. A series of holes are formed in the scale for attaching the scale to the panel at a select radius from a marker carried by the handle for establishing circular cuts.