Case Study: Consulting Engineering
For many years, the University of Louisville Physicians Group aimed to consolidate its services into a single location, offering high-quality pediatric primary and specialty healthcare. CMTA’s consulting and commissioning teams helped make this vision a reality by delivering one of the healthiest and most energy efficient medical office buildings in Kentucky.
This magnificent facility promises to change how health care is delivered to our children...Its design for efficiency of care was not by accident; a number of UofL staff spent...time exploring the best practices from throughout the nation and took the best of those to implement here in Louisville.
Constructed in 2018, the Novak Center is a state-of-the-art pediatric medical office building spanning 174,000 square feet. This modern facility not only focuses on clinical care, but also houses a pharmacy, patient testing areas, clinical research facilities, oncology services, and medical education spaces. Designed with flexibility in mind, the functional program of the Novak Center prioritizes meeting the diverse needs and expectations of patients. The facility provides all the amenities of a standard medical office building, with easily convertible spaces to accommodate Provider-Based Billing Services.
Medical office buildings often operate well over 114 Energy Use Intensity (EUI). The Novak Center, however, operates at an EUI of 39 kBTU/SF/yr, accounting for all electric, gas, central plant steam, and central plant chilled water consumption. This impressive 65% reduction in energy consumption saves the owner $390,000 in annual utility costs. Many traditional energy-saving strategies were used to achieve this reduction, including a variable air volume (VAV) dedicated outside air system (DOAS) with an energy recovery wheel, LED lighting with vacancy sensors, and variable speed pumping strategies. However, these strategies alone did not accomplish the dramatic energy savings achieved. To go beyond traditional energy savings, an innovative approach to HVAC design was also adopted.
The Novak Center is the first medical office building in Kentucky to utilize a highly efficient chilled beam heating and cooling system. The HVAC system is fully ducted and ventilated by a DOAS, and all recirculated air is local to the zone filtered with both MERV 8 and MERV 13 filters. The use of recirculation fans was a major innovation in the design of a chilled beam system. Each recirculation fan zone is capable of operating independently from the DOAS for sensible heating and cooling requirements. The DOAS is only required to meet minimum code ventilation and dehumidification. The active chilled beam system, ducted returns, and final filtration allow for significant flexibility of use for the building.
Built in a major metropolitan area, the Novak Center is serviced by a natural gas and coal-fired central heating plant that is in the process of eliminating coal as a fuel source. The design team’s goal was to reduce the heating requirements of the building, which in turn reduces the carbon emissions and PM particle production from the central steam plant. The first step towards this goal was a high-performance building enclosure that incorporated multiple air barriers and layers of insulation to reduce infiltration and heat loss. The design team performed a building pressure test to confirm the proper construction of the building envelope. Typical building code requires a minimum rating of 0.40 CFM/ft2 leakage rate, and the Novak Center performed at 0.18 CFM/ft2.
The next step was to reduce building reheat. The utilized recirculation fans mixed the cold, dehumidified air with return air to supply warm, dehumidified air to each zone. The primary air temperature supplied to the chilled beams fluctuates between 60°F and 66°F. The 4-pipe active chilled beams then provide any additional heating or cooling to the zone. Due to the efficiency of the heating system, the reduction of downtown gas combustibles is reduced from a typical building’s ~299 Metric tons of CO2e to ~41 Metric tons of CO2e avoided emissions per year—an 86% reduction.
The integrated design process and early coordination were critical to the approval of the chilled beam system. Several charrettes, meetings, and a building tour were required to allow the system design to move forward past the schematic phase. Cost was a major focus of these meetings, as the chilled beam system cost estimated at a $450,000 premium over a traditional VAV system design.
CMTA's Commissioning team oversaw high-level programming of the control system, verifying advanced dewpoint alarm sequences, direct digital temperature controls, building automation, lighting, metering, plumbing, and fire protection. Additionally, CMTA performed an ASTM E779 Building Pressure Test. Throughout the commissioning effort, many issues were uncovered, reported, and remediated. Because the building was both designed and commissioned by CMTA, the shared goals between our teams provided synergy to ensure a successful facility operation.
Indoor air quality (IAQ) is an international focus highlighted by the recent pandemic, but CMTA has known for many years that IAQ impacts life expectancy, health metrics, and cognitive function. A typical office building is served by a VAV unit with plenum returns and MERV 8 filtration. The typical goal of a project is to achieve the lowest cost HVAC system possible to meet code. The Novak Center is a medical office building created for sick children, and many steps beyond the typical design were taken to improve indoor air quality, including: (1) final MERV 8/MERV 13 filtration to ensure elimination of harmful PM2.5 and PM10 particles in an urban environment, (2) zone dehumidification to prevent mold spores from thriving, and (3) ducted returns to allow a cleanable path for recirculated air.
CMTA is proud to have partnered with the University of Louisville (now operated by Norton Healthcare) in designing and commissioning the state-of-the-art Novak Center for Children’s Health. The decisions made in designing and constructing this building will have an impact on the environment over the next 30 years and beyond. The carbon emissions from natural gas production, transmission, and on-site combustion will likely remain consistent over the next 30 years, while electricity production will continue to become less and less carbon-intensive over time. The improved efficiency of this building will reduce carbon emissions from this building by more than 50,000 MT CO2e over the next 30 years—equivalent to 2,175 acres of forest sequestering CO2 over that same period. The building will not only contribute to a healthier environment, but it will promote the health and wellness of patients and staff. This project is a prime example of how CMTA Consulting and Commissioning teams work together to create an energy efficient building that enhances occupant health and wellness.
Typical Office Building TVOC:
Total Volatile Organic Compounds (TVOC) are organic chemical compound groupings to simplify reporting. Consumer products and building materials emit these pollutants, and impact the health of occupants exposed. LEED-NC guidance specifies that the maximum concentration of TVOC in a building (post construction, pre-occupancy) is 500 µg/m 3.
Novak Center TVOC:
After one year of occupancy, the Novak Center’s TVOC level was much lower than a typical office building and surpassed the LEED goal.
Typical Office Building PM2.5:
Fine Particulate Matter (PM2.5) is an air pollutant that can harm people's health by traveling deep into the respiratory tract. Factors such as age and pre-existing health conditions can increase the risk associated with exposure to PM2.5.
Novak Center PM2.5:
The measured PM2.5 in the Novak Center measured significantly lower than a typical office building and performed better than the WELL Building Institute’s threshold of 15 μg/m3.
