You need insulation in your home to provide resistance to heat flow. Heat flows naturally from a warmer to a cooler space. Heat flow can also move indirectly through interior ceilings, walls, and floors - wherever there is a difference in temperature. To maintain comfort, heat gained must be removed by your cooling system. Properly insulating your home will decrease this heat flow by providing an effective resistance to the flow of heat. An insulation's resistance to heat flow is measured or rated in terms of its thermal resistance or R-value. An R-value indicates an insulation's resistance to heat flow. The higher the R-value, the greater the insulating effectiveness.