When Demilec Sealection™ 500 is sprayed into open cavities, the low-density foam expands up to 120 times its liquid volume to fill the cavity. This process insulates and air seals the hard-to-reach areas ensuring a perfect fit every time. Using Demilec Sealection™ 500 in energy efficient homes can reduce heating and cooling costs by up to 50%. Heating and air conditioning tonnage can be reduced as much as 40% without loss of efficiency or comfort.