In multi-story buildings you don't need an accessible route OR an elevator if they meet the following criteria:

1. In private buildings or facilities (owned by a private entity):

-        that are less than three stories

-        or that have less than 3000 square feet (279 m2) per story,

• If the building or facility is not a shopping center, 

• a shopping mall,

• the professional office of a health care provider,

• a terminal depot or

• other station used for specified public transportation,

• an airport passenger terminal,

• or another type of facility as determined by the U. S. Attorney General.

• and in Texas requires access In transportation facilities, any area housing passenger services, including boarding and debarking, loading and unloading, baggage claim, dining facilities, and other common areas open to the public must be on an accessible route from an accessible entrance.

2. In a public building or facility (owned or leased by state and local government)

• That is only two stories

• has one story with an occupant load of five or fewer persons

• does not contain public use space

An accessible route will not be required to the upper or lower floors.

The ADA and TAS has also more specific requirements for special situations.  I am keeping the references to ADA sections for further reading:

1. In detention and correctional facilities, an accessible route shall not be required to connect stories where cells with mobility features (i.e. for wheelchair users), all common use areas serving cells with mobility features , and all public use areas are already on an accessible route.

2. In residential facilities (required by ADA not Fair Housing), an accessible route shall not be required to connect stories where residential dwelling units with mobility features, all common use areas serving residential dwelling units with mobility features, and public use areas serving residential dwelling units are on an accessible route.

3. Within multi-story transient lodging guest rooms (i.e. two story guest rooms) with mobility features, an accessible route shall not be required to connect stories provided that spaces complying with 806.2 are on an accessible route and sleeping accommodations for two persons minimum are provided on a story served by an accessible route.

4. In air traffic control towers, an accessible route shall not be required to serve the cab and the floor immediately below the cab.

5. Where exceptions for alterations to qualified historic buildings or facilities are permitted by 202.5, an accessible route shall not be required to stories located above or below the accessible story.

6.  Per ADA 206.2.4 Exception 3. an accessible routes shall not be required to connect mezzanines where buildings or facilities have no more than one story. In addition, accessible routes shall not be required to connect stories or mezzanines where multi-story buildings or facilities are exempted by 206.2.3 from having to provide access to upper or lower floors.

7. Per ADA 206.2.5 in restaurants and cafeterias, an accessible route shall be

provided to all dining areas, including raised or sunken dining areas, and outdoor dining areas. Except if:

•  a mezzanine contains less than 25 percent of the total combined area for seating and dining

• and where the same d�cor and services are provided in the accessible area.

• In alterations, in existing raised or sunken dining areas,or to all parts of existing outdoor dining areas where the same services and decor are provided in an accessible space usable by the public and not restricted to use by people with disabilities

8. Per ADA 206.2.7 press boxes in assembly areas shall be on an accessible route except in:

• to press boxes in bleachers that have points of entry at only one level if the aggregate area of all press boxes is 500 square feet (46 m�) maximum.

• free-standing press boxes that are elevated above grade 12 feet (3660 mm) minimum if the aggregate area of all press boxes is 500 square feet (46 m�) maximum.

When an accessible route is not required to those excempted spaces, then vertical access is also not required.  So in a multi-story building, or one that has a mezzanine within and they meet the requirements for exemption, then an ramp, elevator, LULA or platform lifts are not required to be provided either.  If the building or space meets the exemption requirement and we choose to provide vertical access, then you have some restrictions on what method to use.  There are no restrictions for using ramps, full size elevators or LULA.  But if you want to use a platform lift as part of your vertical access to those exempted areas, then you may use them but only under certain conditions.

A platform lift is allowed to:

1. Performance Areas and Speakers' Platforms.
2. Wheelchair Spaces at assembly area.
3. Incidental Spaces which are not public use spaces and which are occupied by five persons maximum.
4. Judicial Spaces like to: jury boxes and witness stands; raised courtroom stations including, judges' benches, clerks' stations,bailiffs' stations, deputy clerks' stations, and court reporters' stations; and to depressed areas such as the well of a court.
5. Existing Site Constraints existing exterior site constraints make use of a ramp or elevator technically infeasible.  The words technically infeasible means that you will require a variance from a regulatory agency like in Texas the Texas Department of Licensing of Regulation.
6. Witin guest rooms and residential dwelling Units.
7. Amusement Rides load and unload areas
8. Play Areas play components and play structures
9. Team or Player Seating serving areas of sport activity.
10. Recreational Boating Facilities and Fishing Piers and Platforms. 
11. In an alteration project