ADA Parking Requirements for Commercial Parking Lots
Accessible parking is the most frequently cited pavement-related ADA violation on commercial property, and it is also the easiest to get wrong during a routine re-stripe. The rules come from the 2010 ADA Standards for Accessible Design, and they govern stall counts, dimensions, slope, access aisles, routes, and signage. This guide covers what applies to a parking lot, in the order an inspector reads it.
How Many Accessible Stalls Do You Need?
Counts are based on the total number of stalls in each parking facility — not the whole property combined. Per the 2010 Standards (Table 208.2):
Medical and rehabilitation facilities carry higher ratios: outpatient facilities require 10 percent of stalls, and facilities specializing in treatment of mobility impairments require 20 percent.
Van-Accessible Stall Ratio
At least one in every six accessible stalls — rounded up — must be van accessible. A lot with 4 accessible stalls needs 1 van stall; a lot with 7 needs 2. Van stalls require a wider access aisle and a 98-inch minimum vertical clearance along the vehicle route, the stall, and the aisle. Low canopies, garage entries, and drive-through overhangs are where this fails.
Stall and Access Aisle Dimensions
Access aisles must be level with the stall they serve and must connect to an accessible route without requiring travel behind parked vehicles.
Slope Limits — The Detail Most Lots Fail
Accessible stalls and their access aisles must be no steeper than 1:48 (approximately 2.08 percent) in all directions. This is not a suggestion, and it is the most common measured failure in the Lowcountry, where lots are graded aggressively to move heavy rainfall.
A stall that measured compliant when built can drift out of tolerance after settlement, base failure, or an asphalt overlay that adds material unevenly. If your accessible stalls sit in a low spot that ponds water, assume they need to be checked with a level before your next striping cycle.
Location and Accessible Route
Signage Requirements
Faded or bent signs are a live compliance exposure. See when to replace parking lot signage for a practical inspection routine.
What Inspectors and Plaintiffs Actually Measure
8. Contrast and visibility of the markings themselves
Compliance and Re-Striping in Charleston
The practical risk point is re-striping. A crew that simply paints over what was there preserves any existing violation — including stalls that were never wide enough. Every re-stripe is an opportunity to verify layout against current standards, and it costs nothing extra to lay out correctly the first time.
Charleston's climate compounds this. UV exposure and salt air fade markings faster than inland markets, so restriping frequency matters for both appearance and legal defensibility. Budget guidance is in our parking lot striping cost guide.
This guide is general information, not legal advice. Requirements vary by facility type, alteration history, and local code. Have your specific property reviewed before relying on any count or dimension here.
Need your accessible stalls verified and laid out to standard? Request a free ADA striping assessment or call (843) 628-0398.
