ADA parking: the layout rules every lot has to meet

Most of the lots we restripe have an accessible stall or two, and about half of them have something wrong with it: the wrong count, no van space, an aisle that is too narrow, a sign at knee height, a stall on a slope. None of it is hard to get right. The rules are in the 2010 ADA Standards, and they are specific. Here they are, with the mistakes we see most.

How many

The count is set by the total number of stalls in the lot, from the Standards' table (section 208.2):

Total stalls in the lot	Accessible stalls required
1 to 25	1
26 to 50	2
51 to 75	3
76 to 100	4
101 to 150	5
151 to 200	6
201 to 300	7
301 to 400	8
401 to 500	9
501 to 1,000	2 percent of the total
1,001 and over	20, plus 1 for each 100 over 1,000

Medical facilities have higher counts: outpatient facilities 10 percent of the stalls serving them, rehabilitation and outpatient physical therapy facilities 20 percent. Each separate lot on a site is counted separately.

Van spaces

One in every six accessible stalls, and always at least one, must be van accessible (208.2.4). A van stall is 11 feet wide with a 5-foot access aisle, or 8 feet wide with an 8-foot aisle; it needs 98 inches of vertical clearance over the stall, the aisle and the route to it, which matters in garages and under canopies; and its sign says "van accessible". The missing van space is the single most common defect we find.

Size and the aisle

A car stall is at least 8 feet wide, with an access aisle at least 5 feet wide beside it that runs the full length of the stall (502). The aisle is marked so nobody parks in it, usually with diagonal hatching; two stalls may share one aisle. The aisle has to connect to an accessible route to the entrance without the person crossing behind parked cars where it can be avoided. The international symbol goes in the stall, but a painted symbol alone is not enough: the Standards require a sign.

Slope

The stall and its aisle cannot slope more than 1:48, about 2 percent, in any direction (502.4). That is the second most common defect: an accessible stall striped on a lot that slopes 3 or 4 percent toward the drain, where a wheelchair rolls on its own. If the lot slopes, the accessible stalls go where it is flattest, which may not be nearest the door, and it is the one case where the Standards' "shortest accessible route" rule gives way.

Location

On the shortest accessible route to the accessible entrance (208.3). Where a building has several entrances, the stalls are spread among them. The route from the aisle to the door has to be accessible all the way: a curb ramp with a detectable warning where it meets the drive, no step, no gravel.

The sign

A sign with the International Symbol of Accessibility, mounted so the bottom edge is at least 60 inches above the ground (502.6), where a parked car cannot hide it. Van stalls add "van accessible". Ohio's own parking statute adds wording of its own; the sign suppliers' Ohio signs carry it, and the city building department will say if the local code wants more. A symbol painted on the pavement is good practice and the Standards do not forbid it, but the sign is what satisfies them.

The four mistakes

1. No van-accessible stall, or one that is 8 feet wide with a 5-foot aisle.
2. Stalls on a slope steeper than 2 percent.
3. The aisle hatched but not full length, or shared by two stalls that are not both accessible.
4. Signs missing or mounted low, and the "van accessible" plate forgotten.

When you restripe

Restriping is the moment to fix all of it, because the layout is being redrawn anyway. We count the lot, place the accessible stalls on the flattest ground on the shortest route, draw the van space, hatch the aisles, set the signs at 60 inches, and give you a layout drawing for the file. The line striping page has the rest of what a restripe includes.