Habitat for Humanity - Schenectady: Schenectady, NY

Radiant Floor Heating System

• There was a considerable amount of engineering and design support and a significant amount of coordination required between the manufacturers, designers, and installers of the radiant floor system. For example, the system required a minimum loop return temperature to avoid condensation in the boiler, but the flooring required a maximum temperature to avoid damage to the finished flooring.
• It was very difficult to find a small-capacity, high-efficiency, moderately priced boiler for the radiant flooring system.
• The radiant flooring distribution system was easier to route and required less floor space than the forced air system.
• No significant difference was found between energy usage of the two heating systems.
• Trades working in the house after radiant system installation must be careful not to puncture the tubing. For example, when installing underlayment or toilet flanges, short screws must be used.

View detailed description of Radiant Floor Heating - Dry System Hydronic

Air Admittance Valves

• The use of AAVs saved $293 over conventional venting including four hours of labor and about $50 in materials.
• Due to the home's small size and the stacked bathrooms, material savings and labor savings were not as large as would be expected in a larger or less efficiently designed home.
• The use of AAVs did not significantly affect trades other than the plumbing contractor.
• Two primary advantages to using AAVs was at the kitchen sink which had a window above it and the sidewall venting eliminating the need for a roof vent through the metal roof.

View detailed description of Air Admittance Valves

Additional Information

View evaluation method of these technologies

The plumbing contractor estimated that air admittance valves saved approximately $50 in materials and 4 labor hours for plumbing installation. The use of air admittance valves saved $293 in estimated materials and labor cost, when including plumbing, siding, and roofing contactors. The roof was metal standing seam and flashing around items like plumbing vents is more expensive.

See Resources - Final Report. Table 3: Heating System Cost Comparison.