Floor framing calculator

What you enter

• Floor width (in)
• Floor depth (in)
• Joist spacing (in O.C.)

Main results

• Joist count
• Joist length
• Floor area (sq ft)

What it follows

Plain arithmetic on the width, depth and joist spacing you type; no building-code table is looked up. It counts joists and measures area; it does not check how far a joist can span.

Every result is marked REVIEW REQUIRED. Illustrative project-planning values only; jurisdiction, species, grade, loads, wet service and current adopted tables require review. Do not use a result directly for permit, purchase, or field use.

Related calculators

• Project span table
• Wall framing
• Sheet layout

The calculator opens inside the designer, after you sign in.

Accounts are issued by the DeckAndShed team. There is no self-service sign-up.