Windows Planning Rationale
Views to the exterior, natural light, natural ventilation, passive solar heat gain, and heat loss, should all be considered in the arrangement, location, and sizes of windows. At a minimum, windows shall be provided as necessary to fulfill natural light and ventilation code requirements.
Careful consideration shall be given to the amount and type of glazing to be planned for learning spaces. Natural daylight in classrooms must be maximized and controlled to minimize glare. Window head height, shading coefficient, room finish choices and glare control measures must all be taken into account.
Minimally, Chicago Building Code requirements for light and natural ventilation shall be met and as a minimum CPS requirement, glazing square footage shall account for at least 15-20% as a percentage of total room square footage or the requirements for LEEDTM daylight credits shall be met. No individual window frame size shall exceed 4'-0" X 8'-0".
Windows
- Windows: to be Architectural grade aluminum window assemblies (AW-65 performance grade).
- Storefront Windows: to be utilized only at building entrances, ends of classroom corridors to bring in natural light or other areas where the performance of architectural windows is not required.
- Unitized Window Systems: in lieu of curtain wall systems can be utilized in large fields of windows as appropriate.
- Operable/Accessible Windows (ADA Compliant): Provide a minimum of 2 per classroom to enable evacuation of noxious odors from the room as quickly as possible. Windows shall primarily be fixed or project-out (awning) type. For conditions where double hung is the existing window system, a simulated double hung is to be used with fixed/projected awning and muntin pattern.
- Limiters: Required by code and set to 4" max opening
- Window Sills: Limestone or Cast Stone is required at window sills. Brick sills are not to be used. Continuous sills shall be specified to avoid joints in longer sills. Joints in sills require ongoing maintenance and create drip issues. Sill shall not be flush with underlying wall assembly; they shall include 1 inch minimum projecting edges with integral drip notches and flashings with end dams.
- Window Screens: Provided in operable windows in the cafeteria, servery and kitchen where required by the Department of Public Health.
- Special Acoustic Considerations: Sound Control Windows are required for all buildings in proximity of airport flight paths, train tracks or other noise generating sources.
Window Guards
Metal window guards shall be designed to furnish physical deterrence against forcible entry through windows and to allow emergency egress for building occupants.
- Exterior Guard Locations: All first floor windows and any upper story windows accessible by a low roof or facing a large field or train tracks, adjacent to playground and athletic fields shall be outfitted with window guards. This includes vision panels in exterior doors. Refer to Volume 3, Chapter 2.2.2 Doors/Hardware. For all projects, final locations shall be coordinated with CPS School Safety and Security.
- Interior Guard Locations: Gymnasiums and gymnatoriums (including clerestories)
- Guards: May be integral or applied, however, care shall be taken to facilitate boarding up of glass in the event of breakage. Exterior window guards shall be designed to open from the exterior to facilitate window cleaning. Interior window guards shall be designed to open from the interior to facilitate window cleaning.
- Warranty: Detail window guards in accordance with manufacturer's warranty guidelines so that the installation does not void manufacturer's warranty. Consideration shall be given for other conditions that may necessitate use of guards. Window guards shall be an integrated component included within the window manufacturer's warranty system.
Glass Selection
- Refer to Volume 3, Chapter 2.1.2 Exterior Envelope Materials - Glazing Systems