Putnam County Home,
Putnam County, New York,
USA

Integral to sustainable design, the home’s efficient thermal envelope includes R26 insulated concrete forms (ICFs) below grade on an R10 slab. R26 ICFs continue above grade to the framed R54 roof sprayed with three inches of closed-cell and six inches of open-cell insulation. The home’s efficiency is furthered through a water-to-water ground source heat pump (GSHP) for an Uponor radiant floor heating and cooling system. The heat pumps are fitted with a heater which reclaims energy for domestic hot water storage and dehumidification reheat. 

The home’s in-floor radiant heating and cooling is embedded in concrete for each floor; the basement is slab on grade, and the second and third floors are poured concrete over ICF decking. The concrete thermal mass construction acts as a thermal energy flywheel to offset overnight peak loads so the mass stores energy and regulates temperate fluctuations. 

For radiant cooling, the GSHP system reverses from heating mode to cooling, charging the buffer tank with chilled water instead of hot water. A variable-speed mixing pump controls the water temperature from the buffer tank to the radiant floor cooling system. 

To say the homeowner is pleased is an understatement. “The builder guided me through our joint vision for a highly energy-efficient house comprising a geothermal energy source, radiant heating and cooling, insulating spray foam and web-enabled monitoring and control systems,” he says. “All the planning paid off.”