An Essential Utility from THEBIGUPDATE.COM
ADA Ramp Compliance Planner
Instant Minimum Requirements for US Building Codes (IBC/ADA 1:12)
1. Vertical Rise Input (Total Elevation Change)
2. Mandatory Compliance Results
Input the rise and click Calculate to see the required ramp length, runs, and landings.
CODE REFERENCE:
All calculations use the mandatory 1:12 maximum slope ratio as defined by **ADA 405.2** and follow the dimensional requirements of the International Building Code (IBC) and ICC/ANSI A117.1.
Essential ADA Ramp FAQs
What is the maximum slope allowed for a new ramp?
The maximum slope for permanent, new construction is **1:12**. This is a hard requirement meaning for every 1 inch of vertical rise, you must have 12 inches of horizontal run. Slopes steeper than 1:12 are considered walkways, not ramps, under ADA guidelines.
How many inches can a single ramp run rise?
A single ramp segment cannot exceed a vertical rise of **30 inches** (2 feet 6 inches). If the total rise needed is more than 30 inches, a level landing must be installed to break the ramp into separate runs (ADA 405.6).
What are the minimum dimensions for level landings?
Level landings are required at the top and bottom of every ramp run and must be at least **60 inches by 60 inches** (5 feet by 5 feet). This dimension is necessary to allow a wheelchair to fully maneuver and turn. Landing size may increase if doors open onto the landing (ADA 405.7).
Comprehensive Risk Management: Common ADA Ramp Failure Points
For US project managers and contractors, ensuring ADA compliance is not just about meeting a technical standard—it is a critical exercise in risk management. Non-compliance can lead to expensive remediation orders, project delays, and potentially crippling litigation. Beyond the primary 1:12 slope rule, most failure points occur in dimensional and safety details that are frequently overlooked.
The Cross Slope and Surface Detail
While the running slope is 1:12, the **cross slope** (perpendicular to the direction of travel) must not exceed 1:48 (ADA 405.3). This minute detail is essential for proper drainage and preventing a wheelchair from drifting sideways, which is a major safety hazard. Furthermore, the ramp surface must be firm, stable, and slip-resistant. Using inappropriate materials, or failing to maintain drainage, can lead to both code failure and increased liability, particularly in areas subject to snow or rain.
Handrails: Continuity and Extension
Handrail compliance is a top area for failure. Handrails are required if the ramp run has a rise greater than 6 inches or a horizontal projection greater than 72 inches. The handrail must be continuous and extend **12 inches** horizontally beyond the top and bottom of each ramp run (ADA 505.10). This extension provides crucial support for users stabilizing themselves before and after the change in elevation. If the ramp zig-zags (switchback ramps), the inside handrail must also remain continuous.
The Danger of Open Landings
Where the ramp or landing has a drop-off, edge protection is mandatory (ADA 405.9). This can be a curb, a wall, or railings that prevent a wheelchair from rolling off the edge. This is particularly critical on switchback landings where the ramp design creates sharp turns and exposed edges. Mismanagement of this detail often results in immediate code refusal during final inspection.
Mitigating Legal Risk through Documentation
For US commercial property owners, the risk of an ADA accessibility lawsuit is very real. The key defense is thorough documentation showing intent and adherence to code. Using this planning tool provides a crucial, documented baseline for your design. Remember that the ultimate authority is your local Authority Having Jurisdiction (AHJ) and their adopted building code (e.g., IBC 2021). Always save the results from this planner alongside your blueprints to confirm minimum dimensions were met during the initial planning phase, mitigating future legal exposure.