In efforts to improve indoor environmental quality and energy efficiency, Yale’s Design Standards Committee released updated guidance for enhanced ventilation and a new design standard for variable refrigerant flow systems (VRF). The refreshed ventilation guidance clarifies an approach to evaluating and modifying the use of operable windows for natural ventilation in multi-occupant spaces, while a new design standard defines considerations and requirements for the successful design and construction of VRF systems. This standard covers new construction and renovations in addition to whole, partial, and supplemental uses such as information technology and data rooms.
What are VRF systems?
Variable refrigerant flow systems use heat pumps, piped refrigerant, and branch controllers to provide heating and cooling to individual zones and air handling unit equipment in a building. Like other systems, there are advantages and disadvantages to VRF systems. In the right application, VRF provides energy efficiency, installation flexibility, individual control capabilities, and an approach to decarbonizing heating by using electricity rather than a fossil fuel. Several VRF systems have been cost-competitive compared to other equipment and installed on smaller-scale buildings and partial renovations at Yale. The new design standard incorporates lessons learned from these installations and provides a guide for future selection, design, and construction requirements.
All of the University’s new and updated standard divisions and contractor guidelines can be found online.
Many thanks to all the colleagues who contributed their time and thoughts for this release. Cross-departmental collaboration continues to improve Facilities’ projects and operations.
Please keep your suggestions coming for the next cycle. Feedback will inform the development of new requirements at Yale. Currently under review is a standard for universal all-gender restrooms, which is expected to be published in the next quarter. If you would like a preview, inquire with the Facilities’ Design Standards Committee.
Top image: Variable refrigerant flow systems at Tsai Lacrosse Field House, Yale University, photo by Ronnie Rysz