A lot of effort was put into verifying energy savings in buildings, especially to document the cost effectiveness of daylighting. There was an early assumption that energy efficiency must involve some sacrifice. However, many case studies were showing ways that daylit buildings were benefiting owners beyond the value of the yearly energy savings. There is a long history of daylit retail spaces, however, Walmart’s adoption of skylights was transformational, suggesting that daylighting could not only provide excellent return on investment, but help retailers be more profitable too.

HMG set out to quantify some of these non-energy benefits. In the first study of Ralph’s Grocery stores, all things being equal, daylit stores sold 40% more than their sisters. A second more detailed study of the hardware chair OSH showed a dose-response relationship, and higher transactions associated with more daylit stores.

Yet, despite such evidence, skepticism remained, especially without attribution for the companies studied. Often direct bodily experience of daylight spaces proved more compelling than careful statistical analysis. Even within companies, rapid staff turnover and company acquisitions continually eroded institutional knowledge of the benefits of skylights.

The durable elements of buildings which determine daylight and view will benefit occupants long after the original owners depart. Thus, policies should look beyond immediate financial benefits and advocate for a sustainable ‘loose fit.’