Myth #4: Daylight buildings require clear glass windows or daylit buildings need to be all glass.

Fact: Clear glass windows let in too much light, far more than what's needed for effective lighting. Glare is a common source of occupant dissatisfaction and is caused by too much light resulting in a "cave effect", whereby the rear of the room appears dark compared to other surfaces. Glare can also cause occupants to close blinds or shades requiring overhead lights to be turned on, defeating the purpose of daylight harvesting. Proper daylighting techniques let in natural light and reduce glare; daylight harvesting balances the natural light and electric lighting without distracting occupants, dramatically reducing energy consumption during daylight hours. Effective daylight harvesting depends on the proper placement of windows and skylights and the integration of a lighting control system.

Myth #5: There's only one correct way to daylight, or daylight harvesting = skylighting.

Fact: Specific daylight harvesting techniques vary, depending on location, number of building stories, building orientation and computer use in the building. Daylight harvesting techniques can be adapted to meet the needs of almost any building, whether it's a small commercial building, schools or office buildings. Top-lit designs use rooftop apertures (skylights) to let in daylight as opposed to side-lit which allows light in through windows. Properly- designed skylights are a practical solution in certain situations, such as big box retailers, enclosed hallways or very deep spaces. In most cases, apertures comprising only 3-5% of the entire ceiling are enough to fully illuminate an indoor space, an attractive option to building owners seeking to reduce the bottom line. Solatube International is the worldwide leading manufacturer and marketer of the Tubular Daylighting Device (TDDs), available with a patented 0-10 volt Daylight Dimmer. The GR2400™ system uses traditional daylight harvesting devices to operate the daylight dimmer, programmed to use the TDD as the primary source of illumination, with electric lights dimming up only when photosensors respond that daylight is insufficient. Using TDDs with digital controls will simplify building specs, meet local energy codes, earn LEED credits and reduce power consumption. The GR2400™ pays for itself in reduced utility bills while displacing traditional lighting with daylight by adding TDDs provides an even higher ROI.

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