Laboratory Ventilation Strategies for Existing Buildings

Jeffrey DeGregorio, Payette Associates, Inc.
Michael Walsh, P.E., LEED AP®, R.G. Vanderweil Engineers, LLP

Indoor environmental quality is difficult, but essential, within existing laboratory facilities requiring major renovation. Achieving indoor environmental quality requires that the key points of air distribution modalities, varying internal heat and latent loads within each zone, equipment needs, ventilation rates, fixed floor to floor heights, and the efficiency of the exterior envelope be kept in mind. However, due to recent economic concerns, renovations have become a preferred option for updating laboratory workspaces. Strategies for executing this work within the limitations of the existing building while simultaneously maximizing energy efficiency, all without compromising laboratory safety and the research, is the key to success.

The Harvard Sherman Fairchild Laboratory gut renovation project, which will create laboratory space for the newly created Department of Stem Cell and Regenerative Biology, is anticipating a LEED® CI Platinum rating. Laboratory environmental quality and energy efficiency are the key goals for the multitude of spaces required, including tissue culture, equipment areas, open laboratory areas, imaging, fluorescence-activated cell sorting (FACS)/flow cytometry, and zebrafish.

Planning concepts included a desire for a highly flexible floor plan with a minimal background ventilation rate while meeting the increased density of people and equipment loads. The maximum anticipated program need for fume hood density, internal cooling by zone type, and other critical factors were developed early to establish overall system sizing. This criteria was then used to develop an infrastructure that would allow the owner flexibility in locating each specific space type while not exceeding the agreed upon maximum system size, i.e., right sizing of the system while also optimizing energy use.

During detailed planning of the individual spaces, the most suitable type of terminal cooling and heating required to meet the space requirements was selected. The systems included chilled beams, high temperature chilled water fan coil units, and some limited all air variable air volume areas. General laboratory ventilation air heat recovery is handled by enthalpy wheels. Low face velocity fume hoods were equipped with automatic sash closers to maximize air to this system. In addition, the local sensible only cooling terminal units were connected to an internal heat shift chiller to utilize the heat generated by the equipment to meet space heating needs. The design also incorporated low pressure drop operation of air handling units.

The strategies above led to a system that simultaneously meets the demands of the research, but also are expected to have a cooling energy cost that is 24 percent below and a heating energy cost 37 percent below the ASHRAE 90.1-2007 Section 11 baseline.

Biographies:

Jeffrey DeGregorio joined Payette in 1998 and was promoted to associate principal in 2007. Mr. DeGregorio won the 2005 National American Institute of Architects (AIA) Young Architect Award. Mr. DeGregorio has contributed to the firm's laboratory projects with Harvard University, Massachusetts Institute of Technology, Cornell University, Ohio Wesleyan University, and Biogen Idec.

Mr. DeGregorio is currently leading the gut renovation of the Harvard Sherman Fairchild Laboratory, which is expected to achieve a LEED CI Platinum rating. Mr. DeGregorio is a founder of Payette's Young Designers Core, which was awarded the national AIA Intern Development Program Award in 2002, as well as the founder of the Boston Society of Architects Mentoring Program.

Michael Walsh is a principal with 25 years of experience, of which he spent 23 years focusing on the design of complex laboratory HVAC systems. Mr. Walsh's responsibilities include the development and integration of sustainable mechanical systems to serve biocontainment level 3 (BSL-3), biological, and biomedical research and forensic laboratories. Mr. Walsh is also the lead Labs21 Supporter contact person at Vanderweil. He contributed to the development of the Labs21 Energy Modeling Guide and participated in the development and review of Labs21 Best Practices Guides.