Wall studs create a breach in a home's insulation that lets cold air seep inside. Solid Core backing provides an extra layer of protection to cover the studs and reduce thermal conductivity. It locks out summer heat and reduces winter cold spots on the interior of your home. Solid Core siding delivers four times the insulating power of ordinary siding. It keeps you more comfortable and saves you energy dollars, year-round. The Energy Star logo identifies products which meets the energy efficiency guidelines set by the EPA and the Department of Energy.