How to Calculate a Lumber Takeoff for Framing: A Complete Guide

HOW-TO · 2026-07-21

A lumber takeoff is the foundation of every framing bid — get it wrong and everything downstream gets thrown off with it. Here are the exact formulas contractors use.

A lumber takeoff is the foundation of every framing bid — get it wrong and everything downstream (labor hours, delivery scheduling, profit margin) gets thrown off with it. At its core, a takeoff comes down to a handful of repeatable calculations: stud count from wall length and on-center spacing, plate footage from total wall length, and header sizing from opening widths.

Studs

(Wall length in inches ÷ OC spacing) + 1, with additional studs added for corners and each side of a door or window opening.

Plates

Multiply total wall length by three to account for a double top plate and single bottom plate — though door openings interrupt the bottom plate, so that has to be subtracted separately.

Headers

Opening width plus roughly 3 inches for jack-stud bearing on each side. The header's actual size (2x6 vs. 2x10 vs. an engineered LVL) depends on span tables and whether the wall is load-bearing — this is a lookup, not a formula, and it's the single most common place hand-takeoffs introduce error.

The accuracy gap: waste factor

The real accuracy gap in most manual takeoffs isn't the math — it's waste factor. Studs typically run 5–10% waste, plates around 5%. Skipping waste factor is the fastest way to under-order and stall a job mid-frame.