Improving Health and Wellness Outcomes through Designing for Daylight

Within the design industry, our understanding of the effects of exposure to daylight is growing. This can be seen in the codes and standards which stipulate how much daylight should be provided within buildings—from the FGI Design and Construction of Hospitals, to LEED, to the WELL Building Standard. Studies have found exposure to daylight can help regulate one’s circadian rhythm, improve sleep, and positively affect one’s mood—even reducing the severity of depression. Among students and employees, access to daylight has been shown to improve productivity, while among patients it is shown to reduce recovery time. For this reason, health and wellness organizations should be particularly interested in bringing more daylight into their built environments.

Bring Daylight to Staff and Visitors—Not Just Patients

By code, inpatient hospital rooms are required to have exterior windows. As such, it is very common for any space that is not a patient room to be located on the interior of the building. This can mean that staff and visitors rarely see daylight when in a hospital, which can be disorienting and have negative health benefits. According to the FGI Design and Construction of Hospitals, daylight should be accessible “within 50 feet from any inpatient, staff work, or visitor space.”

In order to bring daylight into more spaces, designers should consider allowing the ends of corridors to lead to an exterior wall ending in a window. Corners of the building can be utilized for staff break rooms or family lounges and waiting areas, while less-occupied spaces like storage rooms and elevators should be centrally located. Staff retention continues to be a concern for health systems, and providing areas of respite can help reduce staff burn out. Locating break rooms or other staff spaces on exterior walls with exposure to daylight can improve staff satisfaction and mood.

Prioritize High-Traffic Areas

According to the WELL Building Standard, 70% of all workstations should be within 25 feet of envelope glazing. In order to do this in a hospital, the building envelope would need to be maximized, increasing the wall to floor ratio. Since envelope is one of the most expensive components of a building, this can have a significant cost impact and may make travel distances unpleasantly long and cumbersome. However, one can still take the ideal and apply it to design.

During programing, architects and planners can provide priorities for room types. One might be the number of staff in a room – a room with ten individuals has higher priority for exterior glazing than a private office for one individual. Another priority might be the amount of time occupied. A room that sees continuous occupancy by staff might be given a higher glazing priority than a room that serves as a touch down point and is only used occasionally. Additional metrics can be added as applicable to the project. Utilizing priorities such as these can help the architect and planner prioritize which rooms are located along the exterior wall and maximize the number of staff who have access to daylight.

Focus on Quality, not just Quantity of Light

The LEED credit for daylight requires meeting a delicate balance of spatial daylight autonomy (SDA) and annual solar exposure (ASE). SDA is intended to measure the amount of area that receives enough daylight for people to work comfortably without electric light, while ASE is a measure of glare, or too much light. Daylight credits can be challenging to achieve for LEED because of the balance that a design needs to achieve – enough light to work most of the time, but not too much.

In northern locations such as Michigan, it can be difficult to achieve a balance of light due to the low angles of the sun. Exterior shading strategies and strategic building siting are key to achieving these daylight goals. On south facades, horizontal shades can help reduce glare in summer months. On the east and west facades, vertical fins can help reduce glare in the morning and evening. Light shelves located on the interior of the building can help push daylight further into the space

A Human-Centered Design Approach for Health and Wellness

As healthcare designers and planners, we should strive to prioritize access to daylight for the majority of occupants, while balancing the overall building floor plate, travel distances, and programmatic needs of the building. Where daylight can be achieved, we can ensure that high quality light is provided—not too bright or too dim. We can also strive to find ways to allow daylight into the building that do not involve entering private rooms, thus providing daylight to all occupants. We can do this through corridors that extend to windows, and with borrowed daylight through transoms and sidelights. Ultimately, access to daylight will help improve overall health, happiness, and outcomes for staff, patients, and guests.

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