What is the “official” layout that is approved by the ADA?
According to PROW-AG R304.1.4 Size, detectable warning surfaces shall extend 24 inches (610 mm) minimum in the direction of travel and the full width of the curb ramp, landing, or blended transition. Setback is 6″ to 8″ within curb line. For more information about detectable warning specifications and the ADA requirements, visit www.access-board.gov.