Commercial secondary windows are retrofit products that are installed over existing windows. Similar to storm windows used in many residential applications, they add layers of glazing or insulation to improve energy performance without the need for full window replacement. Secondary windows are typically designed and produced specifically for each of the window openings in a commercial building. Secondary windows are currently the only commercial product that is rated and certified by AERC.
Interior Roller Shades
Interior roller shades (also called roller blinds) fit inside the window casing, next to the window sash, and are available in a wide variety of fabrics and weaves. They can reduce solar heat gain, darken rooms, offer privacy, and enhance visual comfort by filtering sunlight to reduce eye strain caused by reflections and glare. Automated interior roller shade systems have been shown to block solar heat gain effectively and reduce HVAC cooling loads.
Exterior Roller Shades
Exterior roller shades fit outside the building and are available in a wide variety of fabrics and weaves. They can significantly reduce unwanted solar heat gain, offer privacy, block glare from the sun and darken rooms. Automated exterior roller shade systems may be available and have been shown to block solar heat gain effectively and reduce HVAC cooling loads.
Solar screens are fixed panels that can be installed on either the exterior or interior of a window. They can reduce solar heat gain, UV damage, and glare while permitting significant view and light transmission.
- Reduce cooling loads by blocking solar heat gain
- Effectively block/diminish direct sunlight and minimize reflections, glare, and UV damage
- Among the most economical solutions to solar shading/heat gain issues
The closed cells of these shades trap air and heat that can enhance insulation at the window. Available in single-, double- and cell-within-a-cell formats, cellular shades fold up like an accordion to control daylight, filter glare, and offer privacy.
Blinds feature stacked slats or louvers of metal, plastic or wood, typically connected with cloth tape or with cords that allow them to tilt open or closed to control daylight and privacy, in addition to being raised and lowered. Horizontal venetian blinds stack above a window opening; vertical blinds slide open to the side of an opening and are a common solution for large windows or glass doors.
- Effectively block direct solar heat gain
- Ability to tilt can help reflect daylight into a space while controlling glare
- Increase privacy