(BPT) - A spike in home energy bills often leads consumers to suspect a problem with their heating or cooling equipment. However, before assuming faulty equipment is the cause of high energy bills, it's a good idea to consider other potential culprits that can reduce energy efficiency and lead to costlier heating and cooling bills. Some areas within a home can allow heated or cooled air to escape before it enters the desired room. The attic is a good example of a space where undetected issues can reduce comfort, adversely affect air quality and decrease energy efficiency.
Signs of thermal problems in the attic may be visible from a home's exterior. During cooler seasons, heated air escaping from a home's attic may pass through the roof deck, melting snow or frost. If nearby homes' roofs are covered in snow or frost while your home's roof is bare, this may be a sign of attic heat loss.
Installing a sufficient amount of attic insulation is one way to reduce energy loss. According to Energy Star, homeowners can save up to 15% on heating and cooling costs by air sealing their homes and adding insulation in attics, floors over crawl spaces and accessible basement rim joists.1
Insulate to avoid the chimney effect
The proper level of insulation can help defend against the chimney effect (sometimes called stack effect). This term describes the phenomenon of less dense, warm air vertically flowing to the highest part of a structure - often the attic. Attic insulation functions as a thermal barrier that helps keep warm air inside the home from moving into the attic and escaping to the outside. Conversely, in warmer weather, attic insulation helps keep hot attic air from infiltrating the cooled interior of a home.
A proper thickness of insulation installed in the attic can also help avoid moisture buildup, which can lead to mold growth and potential structural issues. Attic insulation helps maintain indoor temperatures, reduce energy loss and support occupant comfort.
Are your attic ducts in order?
Other attic components can also affect air throughout the home. When ductwork is properly sized and in good condition, airflow is balanced to support comfort and efficient air distribution. Ducts that are too small can cause airflow resistance, resulting in an uneven distribution of air, causing the heating and cooling equipment to cycle more frequently and putting more strain on equipment. Similarly, ducts that are too large may result in lower air pressure and poor temperature control throughout the home. Even acoustics can be influenced by ductwork, as properly sized ducts may help reduce noise generated by air flowing through the ducts.
While duct size matters, so does the condition of ductwork. Holes and loose connections in attic ductwork can allow cooled or heated air to escape before it reaches the register in the desired room. Contaminants inside the attic can enter these breaches and flow into the rest of the home. An increase in dust levels inside the home may be a sign that attic ductwork needs attention.
Inspecting the attic with a whole home approach
A home's energy efficiency relies on a system that includes the heating and cooling equipment, ductwork and ancillary components like insulation. Ensuring that all these components are properly functioning can help contribute to occupant comfort, support indoor air quality, promote energy efficiency and contribute to the longevity of the home's comfort system. An inspection of a home's attic - including measuring insulation levels and assessing ductwork - should be included in HVAC service and maintenance checks.
An Owens Corning AirCare® Professional brings a whole home approach to caring for a home's air. These professionals use the HVAC System Health Check which includes 11 checkpoints to evaluate the home's comfort system. To find an AirCare® professional, visit the Owens Corning online contractor locator.
© 2025 Owens Corning.
