Two Pond Farm is evolving into a small eco-neighborhood in rural Massachusetts. Kraus Fitch Architects led a team to design the first home, built as a model for future homebuilders and a test for alternative and high-efficiency buildings. One of the innovative design features of this home is the system of passive heat storage using thermal mass in the ceiling of the first floor. Structural I-joists were sized to hold about a thousand recycled gallon jugs of water above the ceiling (detail at top right), while a wooden slatted finish ceiling allows air to circulate between the jugs and back into the room. The jugs fluctuate in temperature gradually, balancing the temperature of the rooms below. Passive vents allow air to flow into rooms on the north side of the house, while a heat exchanger helps keep incoming air fresh and comfortable.
The whole house is heated by sunlight and a small point-source heater (a wood stove) in the living room. A pellet stove in a basement art studio provides back-up on especially cold winter nights. Another passive and beautiful feature of the house is the thick plaster on the walls, which acts as thermal mass and balances the level of moisture in the air, helping to prevent excess humidity in the summer, and dryness during the heating season.
Our client for this project, Riverstone Development, received a 2013 Green Giants award from the USGBC-MA West Branch.