Floor Joist Calculator Widget | Calculator Campus

Rim boards Two included (edit in Options) Joist allowance 0% (edit in Options)

Enter the joist span, the floor width across the joists, and the on-center spacing already specified for the project. Total lineal feet includes two rim boards by default; edit that assumption in Options.

Joist span / member length (ft) (required)

Floor width across the joists (ft) (required)

Joist spacing from the plan (required)

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Include two rim boards

Extra joist allowance (%)

Joists to buy

13 joists

Field joists 13 joists

Total lineal feet 188.0 ft

Rim-board length 32.0 ft

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Lineal feet and scope

Count calculation 16.0 ft across ÷ 16.0 in O.C., rounded up, + 1

Allowance added 0 extra joists from 0%

Structural boundary Quantity only — use current AWC span tables or the AWC Span Options Calculator for member size, grade, load, deflection, and maximum span.