Stair Landing Calculator
Calculate landing dimensions, placement, and code requirements for L-shaped and U-shaped staircases.
How It Works
For stairs that change direction, a landing is required. Enter your total rise, stair configuration (straight, L-shaped 90°, or U-shaped 180°), and stair width. The calculator determines the landing position (which step), landing dimensions (must be at least as deep as the stair is wide), and the total footprint of the staircase including the landing. It verifies that each flight between landings doesn't exceed 12 feet of vertical rise (code requirement).
Frequently Asked Questions
When do stairs need a landing?
A landing is required at the top and bottom of every staircase. Additionally, a landing is required when stairs change direction (L-shaped or U-shaped) and when vertical rise exceeds 12 feet between landings. Landings are also required at doors that open over stairs.
How big does a stair landing need to be?
The landing depth must be at least equal to the stair width (minimum 36"). For residential stairs, a 36" × 36" landing is the minimum. The landing width must be at least as wide as the stairway it serves.
What is the maximum rise between landings?
IRC 2018 limits the vertical rise between floor levels or landings to 12 feet (147 inches). For a total rise greater than 12 feet, an intermediate landing is required.