Product design
It should not be expected standard off-the-shelf operable windows can be adjusted to meet accessibility requirements, even if properly located in plan and section. Especially on large windows, achieving ease of operation with restricted motion will likely require specially designed compression weather-seals and low-friction hardware components. Hardware must be selected that ensures windows do not fall shut under their own weight or require two hands to hold closed and lock simultaneously.
Accessible project-out awning vents cannot usually be manually operated due to the requirement for hold-open friction. Out-swing casement vents cannot be hand-operated due to the requirement for one-hand operation. Roto- or swing-arm operators can be provided for both of these vent types, providing mechanical advantage to overcome friction, helping lift the weight of glazing infill, and keeping the operating handle within reach limitations. Special placement of operating handles to achieve low forces may restrict maximum opening.
Project-in hopper vents require glass to be lifted, and typically are not fitted with roto-operators.
Hung windows require the occupant to lift the sash to open, as well as apply added force to overcome friction of sliding weather-seals. Counterbalancing devices may not provide adequate force assistance to get large windows to operate at less than 37.7 N (8.5 lb). Similarly, operation of horizontal sliding sash requires both inertia and weather-seal friction to be overcome. This can limit the applicability of large, manually operated hung and sliding windows in accessible spaces even under new, relaxed ICC/ANSI A117.1 limits.
It is important to keep in mind motorized and mechanical operators have long been available for almost any window type—single- and double-hung, horizontal sliding, parallel-opening, or dual action; as well as the aforementioned projected vents. As long as forces and motions necessary to activate and operate motorized and mechanical features meet the requirements of ICC/ANSI A117.1, these may be deemed accessible operator types.
Use of insect screens may limit accessibility options for certain vent modes and hardware packages. Typically, controls and cords for blinds, drapes, or shades are not required to be accessible.
Operable windows must be located and detailed in a way that meets the reach limitations of ACC/ANSI A117.1 .
Photo © Nels Akerlund
Installation and maintenance
Production-line testing of operating force can help ensure that thewindows leaving the factory comply with AAMA 513-14 requirements. Accessible operating window products require additional care in installation, final adjustment, and maintenance to achieve and maintain compliance. Plumb, square, and level installation is critical. Building settlement can affect operating forces, and necessitate post-installation adjustment.
Standard operable windows cannot always be adapted to achieve accessibility at a later date. The necessary fieldwork varies widely with application and window type—it may be as simple as hardware adjustment, or virtually impossible without complete reconfiguration of window openings and surrounding conditions. If adaptability is desired, the design team is strongly encouraged to develop a window accessibility plan early in the design process, then detail and specify products accordingly.
Terrace and patio doors
The same subcontractor providing windows also often provides doors for access to balconies, terraces, and patios. However, accessibility requirements for doors are somewhat more complex than for windows.
Balcony doors required to be accessible must comply with all requirements of ICC/ANSI A117.1 Section 404. These include:
- reach limitations;
- one-hand operation without grasping, pinching, or twisting of the wrist; and
- maximum 22 N (5 lbf) of operating force to open, not including latching hardware. (The Chicago Building Code has increased the operating force requirement to 38 N [8.5 lbf].)
Door closer manufacturers offer accessible options that limit force-to-open and closing lag time.
As noted, hardware operating force requirements were clarified in the recent ICC/ANSI A117.1 update. Ninety-degree thumb-turn locks are typically made standard on manufacturers’ swinging terrace doors for compliance.
Additionally, threshold height is limited along accessible routes. A minimum width, turning/approach area, and low protrusion limits, as well as requirements for kick plates on swing doors also apply.
Code requirements notwithstanding, accessible terrace and patio doors may be a very desirable feature of the spaces being designed, making it easier for all occupants to enjoy balcony spaces with easy-to-operate door panels and lower-profile thresholds.
