The alternative requirements in 202.5.4.1 through 202.5.4.15 may be substituted for the applicable requirements of Chapter 2 when a qualified historic building undergoes alterations.
Changes of level may be accommodated by ramps having the following maximum slopes:
- A slope between 1:10 and 1:12 is allowed for a maximum rise of 6 inches (1830 mm).
- A slope between 1:8 and 1:10 is allowed for a maximum rise of 3 inches (915 mm).
- A slope between 1:6 and 1:8 is allowed for a maximum rise of 2 inches (610 mm).
- Where access to any space in a qualified historic building will be limited to controlled groups with assigned tour guides, changes in level as provided in this subsection 202.5.4.1(1) may be accommodated by means of a detachable ramp.
Where access to any space in a qualified historic building will be limited to controlled groups with assigned tour guides, requirements of the following Sections are waived for that space.
Where access to any space in a qualified historic building will be limited to controlled groups with assigned tour guides, or where a full-time door attendant or concierge is provided at the door within visual and audible communication range, there are no special requirements for door hardware or operation.
The addition of adapter lever handles that retain the existing hardware will be considered to meet the Secretary of the Interior's Standards for Rehabilitation as they do not result in the removal of any historic features from the structure.
Minimum clear door opening width for a single door or the single active leaf of a pair of doors shall meet the requirements of 404.2.3. When the alteration of an existing historic door does not meet the Secretary of the Interior's Standards for Rehabilitation, a lesser dimension may be considered to be accessible if it provides the highest level of access within the limited dimensions available. Examples of acceptable methods of providing improved access while maintaining the historic door include the following:
- Maintain the door opening area free of any obstructions so that the clear opening can be measured with the door in a 180 degree position rather than the 90 degree position.
- Reverse the swing of the door.
- Remove or alter the side door stop(s).
- Replace the existing hinges with offset hinges.
For pairs of doors where an individual leaf does not provide the minimum clear opening, the following options provide improved access:
- Activating the second leaf; or
- Adding a power operator that activates both leaves.
If it is determined that no entrance used by the public can comply with 206.4 without threatening or destroying the historic character of the building or facility, then access at any entrance not used by the general public, but open (unlocked) with directional signage at the primary entrance may be used. The accessible entrance shall also have a notification system. Where security is a problem, remote monitoring may be used.
Accessible routes from an accessible entrance to all publicly used spaces on at least the level of the accessible entrance shall be provided. Access shall be provided to all levels of a building or facility in compliance with 207.1 and Chapter 4 whenever practical, and where such access would not threaten or destroy the historic character of the building or facility.
Where the alterations to a historic stair do not meet the Secretary of the Interior's Standards for Rehabilitation (as determined by the Illinois State Historic Preservation Office), the requirements of 504 are waived.
Example: The addition of a modern complying handrail on the wall side of a historic stair may meet the minimum requirement for a necessary handrail without alterations to the historic railing and balustrade, thus meeting the Secretary of the Interior's Standards for Rehabilitation. In many instances it may also be possible to install a new code compliant handrail on top of the historic railing and balustrade.
Example: The addition of a modern complying handrail on the wall side of a historic stair may meet the minimum requirement for a necessary handrail without alterations to the historic railing and balustrade, thus meeting the Secretary of the Interior's Standards for Rehabilitation. In many instances it may also be possible to install a new code compliant handrail on top of the historic railing and balustrade.
Full extension of stair handrails shall not be required in alterations where such extensions would be hazardous or impossible due to plan configuration.
If safety door edge is provided in existing automatic elevators, then the automatic door protective and reopening devices as required in 407.3.3 may be omitted.
Where existing shaft or structural elements prohibit strict compliance with the minimum dimensions of the elevator cars as required in 407.4.1, then the minimum floor area dimensions may be reduced to no less than 48 inches by 48 inches (1220 mm by 1220 mm).
In alterations to qualified historic buildings where it is technically infeasible to disperse seating throughout an assembly area, the seating may be located in collected areas. Seating shall adjoin an accessible route which also serves as a means of emergency egress.
Where historic elevator features such as call buttons, hall lanterns, and control panels cannot comply with 407, the addition of new compliant controls that retain the existing will be considered to meet the Secretary of the Interior's Standards for Rehabilitation as they do not result in the removal of the historic elevator features.
Where historic signage including exit signs, directional, informational, and permanent room signage, cannot comply with 216 and 703, the addition of new compliant signage that retains the existing will be considered to meet the Secretary of the Interior's Standards for Rehabilitation as it does not result in the removal of the historic signage.
At least one accessible route from a site arrival point to an accessible entrance shall be required.