Impact of Office Daylighting & Fresh Air on Employee Productivity

Our office environments – where we spend 40+ hours a week – have an impact on our bodies, minds, and health. An unhealthy and uncomfortable environment can cause a variety of problems for workers, from chronic back and neck pain to carpal tunnel to depression. Some of these things are being addressed with standing desks, lumbar supports, and even computer programs reminding to take breaks from the desk. But there are more factors at play in the office than just desk ergonomics, factors that can make the difference between happy, healthy, productive workers and a high turnover. High performance buildings, unlike most conventional buildings, are engineered for comfort and occupant health. Features such as daylighting programs (including solar gain control) and heat recovery ventilation systems for consistent fresh air flow contribute to occupant health and happiness.


Poor overhead lighting in office buildings can cause a number of problems for the employees working underneath them. Eye strain, headaches, and general feelings of malaise are common complaints among office workers. Switching from fluorescent lights to natural daylight can help alleviate these issues, while also helping to boost employee productivity.

What is Daylighting?

Daylighting is the controlled admission of natural light into a building. Skylights and large windows are coupled with an automatic responsive exterior shading system that adjusts throughout the day to let in (or keep out) the right amount of sunlight. (Learn more about daylighting here).

Does Daylighting Really Make a Difference?

We know that access to daylight impacts mental well-being; just look to seasonal affective disorder (SAD) for evidence. There’s also compelling research findings about the human impacts of access to views outside, a close corollary to access to daylight.

Two different studies were conducted within the offices of the municipal utility district in Sacramento, California. The first study tested the performance of 100 workers in an incoming call center and the second study looked at the performance of 200 other office workers using a series of short cognitive assessment tests. At the end of the testing it was clear that views to the outside from an employee’s workstation had a direct affect on workers’ performance:

“A better view was the most consistent explanatory variable associated with improved office worker performance, in six out of eight outcomes considered. Views from a workstation were rated for both primary view (angular size of window view while looking at the desktop computer monitor) and break view (angular size of view from other seated vantage points in the cubicle). Both types of view were rated on a scale of 0-5 first based on size, and secondarily by vegetation content. Workers in the Call Center were found to process calls 7% to 12% faster when they had the best possible view versus those with no view. Office workers were found to perform 10% to 25% better on tests of mental function and memory recall when they had the best possible view versus those with no view.” Windows and Offices: A Study of Office Worker Performance and the Indoor Environment, California Energy Commission, October 2003

Not only did the study find that views to the outdoors boosted employee performance, it found that workers with the best views reported better health conditions, while reports of increased fatigue were most strongly associated with a lack of view.

Another study, this one done at University of Oregon, found similar results. This study looked at the percentage of days missed due to reported sickness analyzed by the different view groups of offices (Group 5 = no view, Groups 1&2 = best views).

Days Missed Due to Reported Sickness Analyzed by Different View Groups Within Offices

As you can see from the graph above, the groups with the best views had the least amount of days missed due to sickness. A “view” provides a variety of things: increased exposure to natural daylight, a pleasing look at outdoor spaces, and possibly fresh air, if the window is operable. These findings show that simply having access to a window decreases the number of sick days taken, which increases the amount of employee productivity naturally (it’s difficult to be productive at work if you aren’t at work).

The Cost of Light

Not only is poor lighting costing employers in terms of employee productivity and happiness, but it’s also costing them in terms of a higher utility bill. According to New Buildings Institute, “Lighting in commercial buildings is responsible for 38% of electricity consumption. When we look at total energy consumed in commercial buildings, lighting is the largest individual use of power accounting for one fifth (20%) of the combined energy total.”

At that high percentage it seems like wanting to reduce electricity use would be a no-brainer. But exactly how much money can be saved by implementing a daylighting strategy?

Windows and Offices: A Study of Office Worker Performance and the Indoor Environment by California Energy Commission estimates that the economic value of energy savings for daylit offices in California from lighting is $3.7 million dollars per year for the first year of new construction. This would increase to $37 million dollars per year after 10 years of accumulated construction. This is based on the average electric costs of $0.1287 kWh in California in 2003. See graph below.

figure66Figure: Energy savings potential for daylit offices in California from lighting controls only for new construction.
Source: Windows and Offices: A Study of Office Worker Performance and the Indoor Environment

Granted, this study is from sunny California and we’re more interested in oft-cloudy Pacific Northwest. In comparison, tenants in the Bullitt Center building (where our Seattle office is located) spent nothing on electricity in 2014. The Living Building Challenge building utilizes a combination of daylighting (which provides 90% of the lighting for the six story building), manual dimming, occupancy sensors, photocells, and standard wall switches (find out more about the Bullitt Center’s lighting here) to keep lighting costs low, while a solar array roof generates more electricity than the building uses.

By implementing a daylighting strategy employers and building owners stand not only to see higher productivity among their employees but also save a bundle in energy costs.


Arguably more important than lighting is air quality. Air: the invisible, yet crucial, element in our work day. It’s common knowledge that oxygen-poor air in enclosed spaces results in heads nodding and eyelids drooping. But there are other ways in which poor ventilation and air quality negatively affect employees and their employer’s wallets. According to World Green Building Council’s Health, Wellbeing & Productivity in Offices report:

“Seminal research in 2003 identified 15 studies linking improved ventilation with up to 11% gains in productivity, as a result of increased outside air rates, dedicated delivery of fresh air to the workstation, and reduced levels of pollutants. A meta-analysis in 2006 of 24 studies – including 6 office studies – found that poor air quality (and elevated temperatures) consistently lowered performance by up to 10%, on measures such as typing speed and units output…Reduced absences may also be a key indicator of the benefits of good indoor air quality for businesses. Short term sick leave was found to be 35% lower in offices ventilated by an outdoor air supply rate of 24 l/s compared to buildings with rates of 12 l/s in a 2000 study. The same study estimated the value of increased ventilation to be $400 per employee per year.”

Lower productivity, higher absences from work, and an estimated $400 per employee per year loss – all due to poor air quality.

The Cost of Poor Air Quality

The invisible foe – poor ventilation – can have an adverse effect on the respiratory system. A sick employee’s cough can spread quickly around an office with poor ventilation. The germs linger in the air longer, increasing chances of contagion. In Health and Productivity Gains from Better Indoor Environments and Their Implications for the U.S. Department of Energy, William J. Fisk, a staff scientist in the Indoor Environment Department at Lawrence Berkeley National Laboratory, estimates the cost of lost work due to respiratory illness (often caused by poor ventilation) is approximately $34 billion:

“Estimates of the productivity losses associated with respiratory illness are based on periods of absence from work and restricted activity days as defined in the National Health Interview Survey (U.S. Department of Health and Human Services 1994). In the U.S., four common respiratory illnesses (common cold, influenza, pneumonia, and bronchitis) cause about 176 million days lost from work and an additional 121 million work days of substantially restricted activity (Dixon 1985, adjusted for population gain). Assuming a 100% and 25% decrease in productivity on lost-work and restricted-activity days, respectively, and a $39,200 average annual compensation (U.S. Department of Commerce 1997), the annual value of lost work is approximately $34 billion.”

That’s a lot of clams.


New Construction

As we continue to develop our urban areas with new commercial buildings it’s important to keep daylighting and good air ventilation in mind when developing the design and program of our buildings.

Providing healthy air to office spaces can be tricky, however, especially in an urban environment where most office structures are located. Natural venting via mechanical windows is good in theory – but in some cases actually does the opposite of what is intended when windows are in close proximity to busy streets. Noise pollution is distracting to workers while the air quality is low due to car exhaust fumes. It’s important to keep site in mind when developing the design for the building. An excellent fresh air strategy is to bring in filtered fresh air through a heat recovery ventilator with balanced intake and exhaust. This ensures a dedicated source of clean fresh air into the workspace while recapturing the heat energy from exhaust air and keeping it inside.

Office Tenant Improvements

While incorporating daylighting into a building is easiest during the design phase, it is still possible to retrofit existing commercial spaces to make use of better air ventilation and daylighting tactics (our Glasswood Passive House Retrofit project is one example, so is our Portland HQ with its sawtooth roof). Get in touch with an architect to explore your options.

If an office TI isn’t in your company’s immediate future, you can try to make the best of your current space by removing obstructions that are blocking windows such as blinds, plants, and cubical walls. With increased natural daylight illuminating the space you are then able to at least reduce the amount of lights that are on. Find ways to add a fresh flow of air through the space by opening up windows and doors, or, if all else fails, you can always buy canned air from Canada to sniff at your desk.


Visit our commercial construction page for more information about our services.


 Featured image of Bullitt Center co-work space. Photo by Brad Kahn.




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