Alnoba, set on 400 protected acres of wilderness, was built to be the first Passive House of its type in New England. Established as a meeting and retreat center, the facility includes a 2,400-square foot main room, as well as teaching and meditation rooms, offices and a fully functional kitchen. The building shell is highly insulated to adhere to Passive House standards, with 12- to 14-inch thick walls and triple-pane, thermally-insulated German windows. Radiant floor heating exists in 75% of the public spaces.

Cornerstone was part of the team that helped bring the owner’s vision for this superbly energy efficient structure to life. Among the systems that Cornerstone commissioned were: two pairs of ground-source, water-to-water heat pumps providing hot and chilled water for the heating and cooling plants, as well as one additional smaller heat pump for domestic hot water; seven cooling fan coil units; four HRVs; and one large ERV that provides fresh air to the building.