Letting the Sun Shine in at the Holiday Inn Chicago Mart Plaza

At the Holiday Inn Chicago Mart Plaza, ultraviolet exposure from the sky-lit atrium caused the hotels front desk employees to experience glare in the morning, making it difficult for them to perform their tasks.

The Holiday Inn Chicago Mart Plaza is located atop the landmark, 24-story mixed use Apparel Center. The hotel sits near the confluence of the East, North and South branches of the Chicago River. The complex was designed by Skidmore, Owing and Merrill, known for designing some of the tallest buildings in the world. The 2.5- million square foot riverfront complex opened in January 1977.

The hotel offers omni-directional views of the City with half its guest rooms having westerly and southern exposure with no overshadowing from nearby office buildings. The 521-room hotel also includes a large sky-lit glass atrium and lobby that receives significant solar exposure. The hotel has 25,000 square feet of flexible meeting space, which includes floor to ceiling windows in its 15th floor meeting rooms.

Direct ultraviolet exposure from the sky-lit atrium, caused the hotels front desk employees to experience glare in the morning until the sun arched across the horizon. This direct exposure made it difficult for them to perform their tasks. Additionally, solar loading created excessive heat build-up on the upper floors of the atrium thus creating uncomfortable temperatures year around.

During the winter months, Air Conditioning had to be run mid-morning to late afternoon to mitigate the raised space temperature. The hotel installed window treatment on the lobby level, but it blocked the magnificent views of the river and skyline.

The Holiday Inn Chicago Mart Plaza is located atop the landmark, 24-story mixed use Apparel Center. The hotel sits near the confluence of the East, North and South branches of the Chicago River.

As in all structures, the exterior of the building had to maintain its prominent design. With its iconic location on the rivers bend, tourists partaking in river tours, Chicagoans on foot, and river traffic viewed the massive structure as they traversed on and near the river.

Guest rooms that faced south and west had solar loading and glare issues. Window treatment was left in varying positions causing a checkerboard effect as viewed from the street thus reducing its curb appeal.

Director of Facilities Bruno LaMountain, looked into ways to improve the comfort and climate of the hotel. At the time, the building was working toward LEED certification and was undergoing a $20-million redesign that included extensive ecological programs including installing window film (to reduce solar loading and subsequently energy costs).

John Parker, president of the International Window Film Association and partner of National Security & Window Filming, based in Oak Forest, IL, was contacted to meet with LaMountain and evaluate what application of window film would be best for the hotel.

Parker and his team came up with a solution and presented it to LaMountain, to install exterior window film designed to the atrium skylights due to the exposure to the elements and another window film for the guest rooms that would provide the protection from solar load and sun damage without darkening the fabulous views from the guest rooms. It was agreed upon and Parker’s team began to install window film. LaMountain tracked their progress by measuring various areas and substrates to determine temperature gradients and noted as much as a 20-degree delta in surface temperatures.

In the guest rooms, window film not only made the temperature more comfortable but it also reduced ultraviolet degradation on wood flooring, carpeting, fabrics, and window treatments.

“Overall we have reduced the temperature in the lobby area significantly, said LaMountain, after the installation was complete in that area. “Now on hot summer days, the HVAC system can easily handle the cooling load while maintaining electrical consumption; we now have extra cooling capacity�?.

The guest rooms were the next phase of installation. Older existing window film was removed and new. More advanced window film installed. Reducing solar load and glare were achieved. Another benefit was the reducing of ultraviolet degradation on wood flooring, carpeting, fabrics, and window treatment. Other benefits include the reduction in the checkerboard appearance from street level.

With the window film project and other renovations completed, the Holiday Inn Chicago Mart Plaza was awarded a LEED Gold Certification by the U.S. Green Building Council.

Next LaMountain is considering having window film installed to the north side of the building to complete the uniform look and capture additional energy savings by blocking ultraviolet rays (window film rejects up to 99 percent of the sun’s ultraviolet rays).

Images courtesy of Holiday Inn