Selecting Windows

Nov 1, 1998 12:00 PM, Raj Goyal

Windows of past generations allowed us a view to the world while keeping weather elements out. However, little else was expected of them. Today, windows are required to do so much more, from protecting against vandalism to keeping noises outside. As technology has expanded, so has the usefulness and functionality of windows.

Schools, colleges and universities have requirements for windows that go beyond letting the light in and keeping the elements out. As the national emphasis on education grows, the need to modernize or build new schools also grows. When making a window selection during construction and planning, consider the following:

-Operational safety.

-Security.

-Heat gain/loss.

-Comfort.

-Condensation.

-Shading.

-Sound control.

-Life-cycle costing.

-Burglary.

-Vandalism.

-Hurricane protection (where necessary).

The technology in the window industry has evolved to provide solutions to all of these concerns. The updated "Voluntary specifications for aluminum, vinyl (PVC) and wood windows, and glass doors" (AAMA/NWWDA 101/I.S.2-97), developed by the American Architectural Manufacturers Association (AAMA), has made it easier to select windows for air, water, structure and thermal performance. AAMA/NWWDA 101/IS.2-97 also has defined the window categories from residential to architectural grade. Select windows for schools that are AAMA heavy-commercial or architectural grades.

AAMA also has added forced-entry resistance testing in these grades to minimize and discourage any burglary attempts. Architectural-grade windows are life-cycle tested for operation and performance over several years of the life of the window.

Addressing safety Safety concerns in windows can be addressed by using tempered glass to minimize injuries due to broken glass under various circumstances.

Schools can address additional safety and security concerns by utilizing high-performance thermoplastics or laminated glass glazing, if the budget allows. Thermoplastic or laminated glazing will add substantial cost to a window project. Security also is provided by adding protection or security screens. Protection screens provide a deterrent at a much lower cost. Protection screens can be used on the second floor and up, and on the ground floor for some applications.

In areas with higher crime rates, security screens may be needed. Security screens will add substantial cost to window projects in comparison to protection screens.

Energy efficiency The Department of Energy and Energy Star Program, as well as the National Fenestration Rating Council (NFRC) have promoted energy efficiency that requires high-performance insulating glass units or dual-glazed sash in windows. The use of low-E glass coupled with tints in an insulating glass unit minimizes heat loss and heat gain, reduces glare, minimizes ultra-violet radiation, provides a higher shading coefficient and increases comfort. The result is substantial savings in heating and cooling costs, which can be used for other maintenance items.

Most of today's window-frame materials provide thermal breaks to enhance the performance of insulating glass units, which minimizes any condensation concerns. Window frames and glass units also can be designed to reduce exterior noise if the classrooms are located in high-traffic areas or close to airports.

Locking up Automatic and/or custodial locks can be added to window units, where needed. Blinds can be added between two glazing lites so the cleaning of blinds virtually is eliminated, in addition to concerns of vandalism or damage to the blinds.

Since the windows are made to be operated in many modes, such as vertical sliders (hung), horizontal sliders, dual action (tilt-turn), project in, project out and casement, it may be necessary to keep the window sash within the wall cavity for safety reasons. Additionally, it is not a good practice to allow the window sash to project into a hallway.

Talk it over It is necessary to discuss specifications and requirements with window professionals in order to specify the best windows for the facility. Window professionals and AAMA members can provide these no-cost consultations to make sure the budget is utilized efficiently.

Do not forget that some schools are located in historical districts, and it is important to replicate windows in profile and sightlines to the original windows. Today's materials can replicate these profiles and sightlines, so it is not necessary to replace windows with the same frame materials as the original.