Vinyl Siding Square & Waste Estimator

When cutting horizontal siding for a gable end, you create unusable triangles at every course. While a standard flat wall only needs 5–7% waste for overlap and end-cuts, a roof with multiple gables and dormers requires a minimum of 12–15% waste to ensure you have enough material to complete the finish-trim.

No, the unit is the same (100 square feet). However, siding is often sold 'per box,' which typically covers 2 squares. Always verify the manufacturer's packaging specs, as some premium vertical or cedar-shake-imitation panels are sold in 1-square or even 0.5-square boxes.