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Home modifications

Ramps

The 1:12 maximum slope (one inch of rise per twelve inches of run) is the benchmark for independent wheelchair use. Less steep is always better where space allows. Steeper than 1:12 compromises independent propulsion and increases tip and runaway risk; if a site cannot fit a compliant ramp, document the constraint and consider a vertical platform lift or an alternate entrance instead of recommending a steeper ramp.

Specifications

Ramp specifications (ADA 405)verify before clinical use
ElementSpecification
Maximum running slope1:12 (8.33 percent)
Maximum rise per run30 in, then an intermediate landing is required
Minimum clear width36 in between handrails
Landing size60 in minimum length, at least as wide as the ramp; 60 x 60 in where the ramp changes direction
HandrailsRequired on both sides when rise exceeds 6 in; height 34 to 38 in above ramp surface
Maximum cross slope1:48
Edge protectionRequired to prevent casters and crutch tips from slipping off the surface

Confirm values against ADA section 405 at ada.gov before clinical use. ADA applies to public accommodations; for private homes it serves as the benchmark.

Source: 2010 ADA Standards

Calculator

Ramp length calculator

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Field notes

  • Rule of thumb from the 1:12 ratio: one foot of ramp length per inch of rise. A 24 inch rise needs 24 feet of ramp plus landings.
  • Landings add real length to the footprint: level landings at top and bottom, plus an intermediate landing for any run exceeding 30 inches of rise.
  • Aluminum modular ramps are the common rental and Medicaid-waiver route for temporary needs; site-built wood ramps make sense for long-term use, and pressure-treated lumber with grippy surfacing handles Colorado freeze-thaw far better than smooth paint.
  • Check door swing at the top landing: the landing must accommodate the door opening without forcing the user to back down the slope.
  • Threshold ramps (under 3 inches of rise) are a separate, simpler product category and usually the first thing to try at single-step entries.

References

  1. U.S. Department of Justice. 2010 ADA Standards for Accessible Design. September 15, 2010. ada.gov