Mayer Hall Addition

Variable air volume control for both the supply and exhaust systems was utilized in the building. Two variable air volume air-handling units supply air-conditioning to the building. Both units serve a combination of laboratory and office spaces. Three laboratory exhaust fans on a common intake plenum provide laboratory exhaust. All equipment was located on the roof. This configuration was designed to allow:

• All horizontal distribution of duct mains occurs on the roof. Three strategically located areas for vertical duct shafts were utilized to arrange supply, return and exhaust risers so that duct mains would not have to cross once the ducts left the shafts. This was done to accommodate the short floor-to-floor height.
• Improved diversity in equipment sizing by serving both space types from a common air handler.
• High efficiency lighting and day lighting control systems reduced heat gain from these systems. Occupancy sensors were utilized in non-laboratory spaces to further reduce the cooling load when unoccupied.
• Fume hood sash stops were set at 18” to reduce laboratory exhaust requirements.
• Duct routing was kept as direct as possible given the space constraints, low pressure drop fittings were used and mains were sized at 1,500 fpm to minimize fan static requirements.
• Velocities at cooling coils and filter banks were limited to 400 fpm to reduce static losses.
• All air handler and laboratory exhaust fans were provided with variable frequency drives. The manifolded exhaust fans are staged and fan speeds are adjusted to maintain a minimum 3,000 fpm discharge stack velocity.
• Since physics labs are not hood intensive, standard variable air volume boxes were utilized in both the laboratory supply and exhaust systems as a cost saving measure. The few hoods in the building were provided with constant volume lab control valves.

Other systems provided include: lab compressed air, lab waste, domestic hot/cold water, low flow plumbing fixtures, complete DDC control system and chilled water from campus central system.

Mayer Hall Renovation

• The existing pressure dependent variable air volume system was converted to a pressure independent operation through the addition of retrofit VAV boxes at each zone and in the lab exhaust.
• The high temperature hot water to heating hot water heat exchanger and pumping system were upgraded. The new system serves the addition as well as the existing building.
• A new electronics cooling water system was provided to serve lab equipment. The system utilizes campus chilled water and a plate and frame heat exchanger. A complete distribution system was provided to serve both the existing building and addition.
• The laboratory compressed air equipment was upgraded and interconnected with the compressed air system in two adjacent buildings to provide redundancy.
• High efficiency lighting and day lighting control systems were provided. 
• Occupancy sensors were utilized in non-laboratory spaces to further reduce the cooling load when unoccupied.