ADA Parking Calculator

General facilities follow a sliding-scale table, while a rehabilitation facility specializing in mobility impairments needs a flat 20% of total spaces and an outpatient physical therapy facility needs a flat 10% -- these are three separate formulas, not points on the same curve, so switching facility type can jump the requirement by many spaces at once.

Van-Accessible Spaces has a built-in minimum of 1, since the 2010 ADA Standards (§208.2.4) require at least one van-accessible space for every 6 accessible spaces in any lot, and this field reports the widest single-aisle requirement present in the lot. The Standards actually offer two compliant ways to provide that van space (§502.2, §502.3.1): a 132-inch-wide van space next to the same 60-inch aisle used for standard spaces, or a narrower 96-inch van space next to a 96-inch aisle -- this calculator assumes the second, more space-efficient option, which is why it reports 96 inches rather than the 60-inch standard-aisle figure.

At least 1 in every 6 accessible spaces must be van-accessible, and the calculator rounds that fraction up to the next whole space with a minimum of 1. A small lot with only 1-5 accessible spaces still needs exactly 1 van-accessible space under this rule.

For general facilities, no -- the ADA sliding scale grows in steps (1 space up to 25 total, 2 up to 50, and so on) rather than a fixed percentage, so the required share of accessible spaces actually shrinks as the lot gets larger. Above 500 spaces the requirement is 2% of the total, and above 1,000 spaces it switches again to 20 spaces plus one more space for every additional 100 total spaces -- a share that keeps falling as the lot grows further, never settling at a flat percentage.