Tunnels and Skyways Boost Sustainability, Whether Hot or Cold Outside
Pedestrians and facilities managers both benefit when tunnels and skywalks are used to connect buildings. From the brutal winters of the upper Midwest to the burning summers of the Southwest, weather extremes impact people and energy consumption. Tunnels and skyways help maintain even temperatures and temperaments.
Some colleges and universities have extensive tunnel and skyway networks. University of Minnesota Twin Cities has a pedestrian network that is six miles long and dates from the 1920’s. In upstate New York, several colleges have pedestrian tunnel networks connecting buildings in order to escape the severe winters. Wright State University in Ohio built a lower level tunnel system that connects all but three buildings, two of which are connected by covered walkway at ground level. The Wright State system is a model for accessibility.
A large number of campuses have utility tunnel systems to distribute heat, electricity, and data. Some of these systems are very extensive. For example, Arizona State University Tempe has a five mile long concrete tunnel system installed 80 years ago to centrally heat the buildings. Michigan State University has steam tunnels that span 12.3 miles and provide heat to over 18 million square feet of facilities.
While the tunnels and skyways contribute to good energy management and sustainability, they can also be places that are difficult to power. It is often less expensive as well as greener to use self-powering egress and exit signs in these spaces. Photoluminescent signs do not require wires to be pulled and therefore require less investment and labor to meet building and fire codes. The aesthetics and long viewing distance of these signs also complement the long, simple hallways of tunnels and skyways.
New tunnel systems are likely to be illuminated with energy saving LED light sources. It’s therefore very important to use photoluminescent signs that can be charged with LED light and which meet the UL924 safety standard. Utility tunnels can be full time workplaces for engineers and maintenance staff, so the lighting and exit signs should be equivalent to lecture halls and offices.