Added insulation in the attic will make the upstairs rooms more comfortable in the summer. It will also reduce your cooling and heating loads, saving you money on your utility bills.
Just to give a rough idea of your savings, consider this: Let’s assume your attic is 1,500 square feet and it is currently insulated with 6 inches of loose-fill fiberglass for R-13. On a hot summer day when the attic temperature is around 120°F, the heat gain into the living space through the ceiling is 5,800 Btu per hour. Nearly a half ton of air conditioning would be needed to take care of that heat gain.
Adding 16 inches of cellulose over the existing insulation will give you R-38, dropping the heat gain from 5,800 to about 1,250 Btu per hour—a reduction of nearly 0.4 tons of air conditioning, which will make it easier for your upstairs cooling system to keep the temperatures lower.
Before adding new insulation, seal all of the air infiltration pathways between the living area and the attic—including around wiring, plumbing penetrations, ceiling light fixtures, vent fans, and the attic hatch. In many homes, these leaks are the single largest source of air infiltration, and plugging them will reduce your heating and cooling bills and reduce the chance of moisture problems in the attic. This sealing is a lot easier to do before the new insulation goes in. This is also a good time to seal and insulate any heating or cooling ducts in the attic.
At AtticFiveStars we offer every service detailed above.