Energy Efficiency / Weatherization: Reducing your energy usage by eliminating energy waste through ineffective measures. Weatherization is a modification to the building shell (your house) to help reduce energy usage and enhancing air quality between living area and outdoor space. For example, insulation in walls/ air sealing your home helps keep the heat in and fills the empty space where air would otherwise enter. Furnace or boilers making sure they are sized right and efficient. The benefits of being energy efficient and weatherizing your home: lower greenhouse gas emission, reduce utility demands, and helps save money on your utility bills.