Do I Need to Place Insulation on Top of a Suspended Ceiling or in the Ceiling Joists?

Insulation Benefits

• Insulation in a suspended ceiling or elsewhere in your home is similar to wearing a coat in the winter. The insulation traps the heat inside the home; therefore it doesn't escape outside. This results in lower utility costs in cold months, as well as preventing cooled air from exiting the structure during hot weather. Insulation ensures that you and your family members are comfortable inside the home despite the outdoor temperatures and weather conditions.

Determining Insulation Needs

• If your suspended ceiling is below another story of your home that maintains the same temperature, there is no need to install insulation. Another reason for not installing insulation is if the suspended ceiling is in a basement area. The heat from the area above the basement flows through to heat the basement area. If you install insulation, this reduces the heat flow efficiency.

Roll or Batt Insulation

• Follow the manufacturer's directions for installing roll or batt insulation. Installing this type over the ceiling joists and perpendicular to the ceiling ensures that the weight does not cause the ceiling to sag. The weight rests on the suspended ceiling grid system, thus eliminating any potential sagging. This also provides air space between the suspended ceiling and the insulation, preventing moisture problems as long as you do not use a vapor barrier. Do not leave gaps in the insulation as this defeats the purpose by allowing hot or cool air to escape.

Safety Reasons Not to Insulate

• Proper ventilation is sometimes necessary in the area between a suspended ceiling and the floor above it for the correct airflow in the structure. This is also an important consideration for fire safety within the building. If you cannot use insulation safely in your suspended ceiling, consider replacing it with insulated ceiling tiles that eliminate the need for added insulation.