Design Challenge

The Willow School, a private preparatory school in Gladstone, New Jersey wanted to build a model environmental building for its health, wellness, and nutrition programs. The school established high environmental goals for the project, including that the building receive certification by the Living Building Challenge. Certification by the LBC requires that the building be net-zero energy, net-zero water, and meet other highly rigorous environmental requirements. The building houses the school cafeteria/multipurpose space, a teaching kitchen, and classroom facilities. To achieve these goals, the school sought assistance from experienced net zero building designers.


Maclay Architects was hired by the owner to lead the design of the envelope and overall net zero strategies. We provided recommendations on kitchen and refrigeration, daylighting, mechanical systems, and structural design. This work included pre-design services to develop metrics for the team to target. We provided advice during design phases and then supplied all envelope construction drawings and specifications including LBC red list coordination. Throughout construction, we provided consulting to ensure net zero performance and an actual Energy Use Intensity (EUI) consistent with the modeled EUI. The EUI for the project was projected to be 15.9 kBtu/sf-yr for all loads, except for process loads including the commercial kitchen equipment and ventilation, which were an additional 6 kBTU/sf-yr. The actual use has been measured at 25.9 kBTU/sf-yr.


Construction of the building was completed in the summer of 2015 and it has received LBC certification. Other notable highlights include near daylight autonomy, net-zero energy performance (by use of solar photovoltaics), and compliance with the LBC red list.

Project Details


Gladstone, NJ




18,280 sf


Full Living Building
Challenge Certified

Energy Intensity:

21.9 kBTU/sf-yr (modeled)
25.9 kBTU/sf-yr (actual)
-16 kBTU/sf-yr
(actual, with renewables)