No Blinding Light
- By David H. Martin
- 12/01/11
Conventional venetian blinds were once a favorite alternative to fabric drapes and window shades in classrooms. Tilting the slats would provide a moderating thermal effect by reflecting unwanted solar heat, and in the heating season, helped to keep in precious building warmth.
Today commercial grade windows for K-12 classroooms often include internal features that contribute to students’ thermal comfort. One such feature is between-the-glass venetian blinds (sometimes called interstitial, internal or integral blinds).
Pella invented the first internal venetian blind systems for their residential wood windows and patio doors many years ago. Today, commercial heavy aluminum frame windows can be custom ordered with integral aluminum blind systems that provide flexible shading and privacy as well as enhanced human comfort. “Part of the comfort equation is improved acoustical performance from the additional air space,” says Winco Window Company technical sales manager, Kurtis Suellentrop. “Internal blind sash in a structural aluminum window can temper potentially disturbing external street noise, for a less distracting learning environment.”
Internal window blinds also add up to a more hygienic classroom environment. Since the blinds are suspended inside the glass panels, dust can’t get to them. In fact they never need to be dusted, protecting the students and teachers from breathing airborne particles when in-room maintenance is performed by janitorial staff. They’re a maintenance time-saver, too.
That’s because blinds protected by glass panels are virtually maintenance-free. Dust-free and never needing to be cleaned, internal blinds are 100 percent protected from damage, unlike exterior blinded systems. Unlike fabric drapes and colored shades, there is no UV degradation. Aluminum slats in some window blind systems are finished with an organic primer and baked-on enamel finish coat. Extruded aluminum rails are mounted with snap-in clips.
Some integral blind systems can be manually tilted and raised. Others can only be raised. Operating functions can be controlled by accessible tilt control knobs and lift cords made of braided synthetic yarn tested to minimum tensile strength of 130 pounds force, according to Suellentrop. Others can be motorized, enabling staff to control — at the touch of a button — daylight, the view and mood of the learning environment.