2010 ADA Standards for Accessible Design Pocket Guide
502.5 Vertical Clearance.
Parking spaces for vans and access aisles and vehicular routes serving them shall provide a vertical clearance of 98 inches (2490 mm) minimum. [S.H. 4.6.5]
Advisory 502.5 Vertical Clearance. Signs provided at entrances to parking facilities informing drivers of clearances and the location of van accessible parking spaces can provide useful customer assistance.