According to studies done by the Department of Energy, 50 percent of the heat loss experienced in the average home occurs through the ceiling. That makes a lot of sense since heat rises. You can reduce that heat loss (heat gain in the summer months) by adding another layer of insulation in the attic. That will hold more heat in our homes for a longer period of time which means the furnace will cycle less. That means you are going to save money. A lot more money than another layer of insulation costs. Additionally, having an attic fan controlled by a thermostat installed in your attic will remove a lot of heat in the summer. This will help you, in addition to having more insulation, reduce heat gain from the attic in the summer.