Project Awards ACEC – New York, Engineering Excellence Gold Award, 2025

By Matt Meyer, PE

Milne Library is a much-loved, visible, and busy building on the campus of State University New York (SUNY) Geneseo. It is a place to study, gather, grab a bite, and connect. It’s also nearly 50 years old and until recently had been showing its age.

The library’s asbestos-based spray-on fireproofing had failed and had fallen on top of all the buildings’ ceilings. For years, no one could run new service or wires above the ceilings because of the hazard, creating an awkward exoskeleton. While a renovation of the library wasn’t planned until 2026, it became clear it would be cost effective to renovate it earlier (starting in 2020), while also mitigating the asbestos hazard. Budgets were shifted to allow this scheduling change.

That meant the 75,200-sf library would be the first deep energy retrofit project the campus completed under SUNY’s energy- and carbon-reduction goals (Directive IB-2), and one of the first in the SUNY system. A deep energy retrofit is an energy conservation project in an existing building that improves its building performance.

Pathfinder, now IMEG, provided mechanical, electrical, plumbing, and fire protection engineering design, energy services, and construction administration for a comprehensive building review, program study, and the deep energy retrofit for the project, completed on behalf of the State University Construction Fund (SUCF). It is on track to achieve LEED Silver (v4.0) certification. That goal and the IB-2 directive pushed the design team to get creative.

For example, the team designed a high-performing, fully electrified mechanical system. The HVAC system features all-electric, high-efficiency extended-range air source heat pump boilers and optimized air-cooled chillers with dedicated outdoor air systems (DOAS) for building ventilation. The system stands alone from the natural gas-powered district steam loop at the central plant. When the project was designed in 2020, this was relatively new technology.

That system was designed as a stop-gap measure. The fossil-fuel burning district steam loop eventually will be converted to a clean energy source and may include a large-scale ground source heat pump to circulate chilled water and low-temperature hot water around campus. The design strategically set Milne Library up to receive that low-temperature hot water and chilled water, so when the switch is made, the air-source heat pump boilers can be decommissioned and the building tied into the clean district loop. This choice meant the owners weren’t committed to fossil fuels for another generation.

The building also had two fairly new air-cooled chillers for air conditioning. They were reused, with set points adjusted to optimize efficiency. Our energy modeling team vetted the setpoints through multiple iterations of modeling runs to ensure the most efficient modifications were made.

Vertical-type four-pipe fan coils units, connected to a ducted supply air system, deliver conditioned air to ceiling-mounted air diffusers installed in each room. These units are in the attic and strategically placed closets throughout the building. Ventilation air is supplied to each fan coil unit via the DOAS units, using CO2 sensors for occupancy tracking (demand control ventilation or DCV) to deliver required ventilation air to all occupied spaces. Designed during the COVID-19 pandemic, MERV 13 filters became a design standard. This ventilation air delivery method provides 100% outdoor air into control zones. Also, a 75% efficient enthalpy (sensible and latent heat) heat recovery wheel preconditions the outside airstream, further conserving energy.

The design team also used control strategies such as demand control and ventilation to deliver code-required ventilation air to the terminal equipment that provides heating and cooling for the building. The system design tracks the occupancy (transient over any given day) and tunes ventilation air delivery to the building, adjusting it based on occupancy, which saves energy.

The special collections and archive room houses historic books, manuscripts, and regional artifacts. This area of the building was mechanically isolated and provided with its own unit with dehumidification and humidification capabilities to maintain tight temperature and humidity control. A separate clean agent fire suppression system serves the special collections area to ensure a fire would not completely damage or destroy the historical contents.

Other energy-saving systems included:

• Electrical upgrades featured new LED lighting throughout the building, a motor control center, fire alarm system, data and communications systems, and access control and security systems.
• The project upgraded emergency/standby power system capacity to 300 kW and provides a separate power panel for life safety loads and standby power loads for latest code compliance.
• Plumbing upgrades include new domestic hot- and cold-water systems, plumbing fixtures, sanitary drainage and vent systems, natural gas, fire protection and storm water drainage.

The project exceeds the energy performance goals set forth in the1B-2 Directive with a modeled 46.8 EUI (kBTU/sf-yr), which is 23% better than the target goal of 60.1 EUI, demonstrating its environmentally conscious design and commitment to reducing energy consumption. The project also reduced site greenhouse gas emissions by 75% compared to an ASHRAE 90.1 code baseline building. Pathfinder, now IMEG provided energy modeling and HVAC systems analysis under a NYSERDA contract, helping to procure $112,000 in performance-based financial incentives.

Many think deep retrofits and sustainability initiatives will always increase the budget, but this project met or exceeded the SUNY sustainability goals and will earn LEED Silver certification while being about $1 million under budget and opening on time.