AS/NZ 1680 recommended light levels is 320 lux for a desk. Even on an overcast day, direct sunlight can be as much as 10,000 lux. This glare causes severe discomfort and can be as disruptive as no light at all.

Vertical windows are commonly used in many projects throughout the world as we all know the health and productivity benefits of natural daylight; and they provide occupants with the important view outside.

However, solely using vertical windows, traditional skylights or large glazing to introduce natural daylight into spaces will also typically create problems with shifting patterns of light and consistency of the light, producing glare. Glare can cause discomfort and eyestrain to the occupants which is counterproductive.

The way most occupants solve the glare issue is by using sunscreen blinds or shades; essentially blocking out the natural daylight. Another solution to mitigate glare is to combine natural daylight from vertical windows with that from a Tubular Daylights Device (TDD) such as a Solatube. A Solatube TDD serves to provide a highly consistent and controllable working source of light and will help balance the interior's natural light.

This combination of vertical windows and Solatube TDD’s was the solution that DPR Construction and Smith Group Architects used in Phoenix, Arizona.

Rising from the remains of a circa-1972 boutique, this reconstructed 15,036m² building incorporates innovative features to improve energy efficiency. Holistically designed with environment and comfort of its employees in mind, the new office integrates alternative ways to light the space; the expansive walls of windows and 82 strategically positioned Solatube units nearly eliminate the need for artificial daytime lighting 365 days a year and reduce the glare from direct sunlight.

The result is no glare, no need for shades or blinds, a strong connection to the outside, and less energy consumption for heating and cooling equipment.