Project span table calculator
Compare a requested joist span with the same AWC table row the deck model uses for this project's species and jurisdiction.
What you enter
- Member category
- Size and spacing
- Requested span (ft)
Main results
- The span you asked about
- Tabulated span limit
- Span the deck model releases
- Verdict (for example BLOCKED OVER SPAN or ENGINEER REVIEW)
- Which table row was read and what it does not cover
What it follows
Compares the span you ask about with a published span table row for the project's species, size and spacing; which table is read depends on the project's jurisdiction. A span the table does not release is marked ENGINEER REVIEW or BLOCKED OVER SPAN. Rafters are compared with an illustrative table only. The local authority (AHJ) has the final word.
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.
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The calculator opens inside the designer, after you sign in.
Accounts are issued by the DeckAndShed team. There is no self-service sign-up.