Open plenum vs. dropped ceiling: The debate over life cycle cost

While suspended, lay-in ceilings have long been the norm in commercial design, the open-plenum ceiling has become trendy and economical, particularly in office and retail environments. However, calculating the tradeoffs between cost and performance can be tricky.

Very little data exists comparing suspended ceilings with open ceilings on the basis of cost and performance. The most recent study came from the Ceilings & Interior Systems Construction Association (www.cisca.org) five years ago. In the study, office and retail spaces were modeled in Chicago, Charlotte, Oklahoma City, Orlando, and Phoenix to reflect the differences in energy costs, climate, and installation costs. Initial construction costs were determined using RSMeans data; annual operating costs for HVAC, lighting, and maintenance were calculated according to Building Owners and Managers Association data.

The study found initial construction costs for suspended ceilings to be 15-22% higher in offices, and 4-11% higher in retail spaces. However, total energy savings for lay-in ceilings vs. open plenums were 9-10.3% in offices and 12.7-17% for retail. A 10.5% energy reduction qualifies buildings for a LEED EA credit, and a 14% reduction is good for two points.

The study attributed the energy performance advantage of suspended ceilings to the use of a return air plenum with low static pressures and fan horsepower vs. ducted air returns with higher static pressures and fan horsepower in open-plenum systems. In addition, return air plenums more efficiently remove heat from lighting systems and reduce the AC load. Suspended ceilings also offer about 20% higher light reflectance, thereby reducing lighting costs.

For more information, see: http://www.cisca.org/files/public/LCS_brochure_rev_9-08_lo-res.pdf.

The majority of fire rated glazing applications occur inside a building to allow occupants to exit the building safely or provide an area of refuge during a fire. But what happens when the threat of fire comes from the outside? This was the case for The Kensington, a mixed-use residential building in Boston.

All renderings, plans: courtesy Payette and Northeastern University

| Apr 8, 2014

Science, engineering find common ground on the Northeastern University campus [slideshow]

The new Interdisciplinary Science and Engineering Building is designed to maximize potential of serendipitous meetings between researchers.

| Apr 8, 2014

40 Under 40 winners: Meet the contractors

Of the up-and-coming AEC professionals to be named to the class of 2014, nine make their living as contractors.

Wyatt Frantom, Associate and Senior Architectural Designer, Gensler, Los Angeles

| Apr 7, 2014

40 Under 40 winners: Meet the architects

Of the up-and-coming AEC professionals to be named 40 Under 40 winners by the editors of Building Design+Construction, 21 make their living in the architecture profession.

| Apr 3, 2014

Security, accountability, and cloud access: Can you really have it all?

I’ve heard countless stories of conversations between project engineers and IT professionals who can’t come to an agreement on the level of security needed to protect their data while making it more accessible—not only externally, but also internally.

| Apr 2, 2014

The new model of healthcare facility management

A growing number of healthcare organizations are moving to an integrated real estate model in an effort to better manage costs, respond to regulatory requirements, and support changes in patient care delivery.