Guide to the ADA Standards

When alterations are made on an upper story of a facility, is vertical access required?

If an alteration includes installation of a stair or escalator where none existed previously and involves major structural modifications, an accessible route between levels served by the stair or escalator is required (unless an accessible route already exists). If alterations are made to a primary function area on an upper floor, an accessible path of travel to the area is required to the extent that the cost is not disproportionate (i.e., more than 20% of the cost of the overall alteration). In any alteration, an accessible route between stories is not required in a facility that qualifies for those exceptions permitted in new construction based on the number of stories or square footage per floor.