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Home / Code Guides / Ramps

Residential Ramp Code — Slope, Landings & Handrails

The IRC’s ramp rules are short: one slope limit, one exception, landings where you start, stop, turn, or pass a door, and a handrail once the ramp climbs more than 6 inches.

RequirementModel Code StandardSection
Maximum slope1 unit vertical in 12 units horizontal (8.3%)IRC R311.8.1
Steeper exceptionUp to 1:8 permitted only where a 1:12 ramp is technically infeasible due to site constraintsIRC R311.8.1
LandingsMinimum 36 in. × 36 in. landings at the top, at the bottom, where doors open onto the ramp, and where the ramp changes directionIRC R311.8.2
Handrail triggerA handrail on at least one side wherever the ramp rises more than 6 in. between landingsIRC R311.8.3
Handrail height & grip34–38 in. above the ramp surface, continuous for the full length, with the same graspability rules as stair railsIRC R311.8.3.1–R311.8.3.3
GuardsOpen sides more than 30 in. above grade require a 36 in. guard with openings that reject a 4 in. sphereIRC R312.1

Worth knowing

  • At 1:12, every inch of rise costs a foot of run plus landings — a 24 in. porch height is a 24 ft ramp before landings. Measure before promising a straight shot.
  • ADA standards (1:12, 30 in. max rise per run, two handrails) govern public accommodations, not private homes — but they are a sound spec when building for a wheelchair user.
  • Cross slope matters too: keep it at or under 1:48 or wheels track sideways in rain and ice.
  • Wood ramp surfaces get slick — composite boards or grit strips are cheap insurance, and some jurisdictions require a slip-resistant surface.
Sections cite the 2021 International Residential Code and 2023 National Electrical Code as model standards. This is BuildSpec’s own summary — not ICC or NFPA text; read the authoritative language at codes.iccsafe.org. Your state may be on a different edition with amendments — check your jurisdiction page or get an Address Report.
Deck Footings →Deck Ledger →GFCI Protection →Egress Windows →Stairs →Handrails & Guards →