House Not Cooling? Check the Attic’s Insulation

If poor cooling performance is an issue, before you blame your HVAC system, check out your air sealing and insulation status first.

Insulation of attic with fiberglass cold barrier and reflective heat barrier between the attic joists

Source: istockphotos
Attic insulation in place

Heat energy is always in motion and enters a home by direct air leaks or by conduction and radiation resulting from inadequate insulation. Particularly in the attic, proper insulation forms the vital barrier to stop heat infiltration that makes your A/C struggle to keep up with the cooling load.

Many homes were built with only a few inches of attic insulation and are severely under-insulated by today’s standards. Move into the 21st century by upgrading air sealing and insulation and lower cooling costs while boosting comfort. An HVAC professional can perform an energy audit to assess the air tightness of your home as well as the amount and quality of insulation.

First, Seal Leaks

Installing new insulation doesn’t stop direct air leakage. Therefore, first locate ceiling cracks and gaps that allow hot air to flow between the attic and living spaces. Use caulking to seal around the joint between the walls and ceiling, as well as around recessed ceiling lights and any openings where plumbing pipes or vents enter the attic. Install weatherstripping to seal the attic access hatch or pull-down stairs, too.

What Kind Of Insulation?

Insulation is upgraded by adding new material atop existing layers. New layers can be of a different type, too. Most attic insulation is either pre-cut fiberglass batts—that pink, cotton candy stuff that rolls out between ceiling joists—or cellulose loose-fill, pulverized bits of paper and fabric blown into the attic by compressed air.

How Much Insulation?

Insulation’s effectiveness is rated by its heat resistance or “R-factor.” Recommended insulation is expressed by total R-value: the base R-factor times the installed depth in inches. Here in southern Ohio, the Department of Energy recommends insulating the attic to at least R38.  For fiberglass batts, that translates to a minimum of 12 inches in depth and, for cellulose loose-fill, at least 10 inches.

For more on the virtues of proper air sealing and insulation, contact the professionals at Apollo Home Heating, Cooling and Plumbing.