Friday, January 21, 2011

NFRC and Daylighting Ratings

By Jim Benney

By providing independent and accurate daylighting ratings, NFRC could offer a more complete picture of the vital role fenestration plays in buildings. One of the most well-known roles fenestration plays is reducing electricity consumption associated with indoor lighting.

A lesser-known and perhaps equally important role, however, is the profound effect daylighting has on worker productivity.

While daylighting has been shown to benefit many areas of human health and performance, one of the most notable areas is worker productivity.

In fact, studies conducted by the Heschong Mahone Group (HMG), a California consulting firm, show a strong correlation between daylighting and improved productivity.

Some of HMG’s specific findings include the following:

  • Office workers exposed to the most daylight consistently reported a higher level of concentration and better short-term memory recall
  • Workers in the Sacramento Municipal Utility District’s customer service call center processed calls 7 percent to 12 percent faster when they had the best possible view, versus those with no view 
  • Computer programmers exposed to daylight spent 15 percent more time on their primary task, while equivalent workers without exposure to daylight spent 15 percent more time talking on the phone or to one another
Making optimal use of daylighting to bring out the best in office workers is an initiative well worth pursuing. Even small improvements in productivity can add up to big benefits over time.

The bigger question is – how do we quantify these benefits? Energy savings through daylighting is one thing, but what about productivity, comfort, and health? How can we help to evaluate these criteria and offer a metric to building owner, the code community and/or LEED?


Jim Benney is the National Fenestration Rating Council’s chief executive officer. He has been involved in developing product and performance standards for the window and glass industry for more than 20 years. He can be reached at
jbenney@nfrc.org.