L stair calculator
Estimate two flights and a quarter-turn landing while keeping the connection under review.
What you enter
- Total rise (in)
- Maximum riser (in)
- Tread run (in)
- Landing width (in)
Main results
- Number of risers
- Number of treads
- Total run
- Stringer length of the longest flight
- Landing width
- Rise, treads and run of each flight
- Connection review note
What it follows
Plain geometry on the rise, riser, tread and landing width you type; no building-code table is looked up. The maximum riser is a number you type; check the limit that applies where you build. The connection between the two flights is marked as a handoff for review.
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.