Leaky Ductwork: The Heating Loss You May Not Notice

Your furnace can be working properly while some of its heat never reaches the rooms you want to warm. Gaps at duct joints, loose connections, and damaged sections can let heated air escape along the way. November is a practical time for Pittsburgh homeowners to investigate these hidden losses before winter puts more demands on the heating system.

Where the leak happens makes a difference. Supply ducts leaking into an unconditioned attic, garage, or crawl space send heat outside the areas you intend to heat, while return-side leaks can pull unwanted air into the system. Even leaks within the heated portion of a home can interfere with airflow and temperature control.

Start with a visual check of accessible ductwork without removing equipment panels or entering unsafe spaces. In a Carnegie home with exposed basement ducts, for example, look for separated joints, hanging sections, or old sealing tape peeling away from connections. A whistle or a noticeable stream of air at a joint while the blower runs can suggest a leak, but noise alone does not establish the cause.

Duct sealing is not the same as wrapping every joint with ordinary cloth-backed duct tape, which can deteriorate over time. Appropriate repairs typically use duct mastic or UL 181-rated sealing products selected for the duct material and application. Leave inaccessible ducts, major disconnections, and repairs near heating equipment to a professional, and do not disturb older duct insulation or wrapping that could contain asbestos.

For a Wexford homeowner considering a new furnace, checking duct condition before choosing equipment can help avoid carrying an existing airflow problem into the new installation. A technician can evaluate connections, insulation, airflow, and static pressure to determine whether leakage or another restriction needs attention. Sealing and insulating serve different purposes: sealing limits escaping air, while insulation slows heat transfer through the duct walls.

If you suspect your ductwork is losing heated air, contact MRT HVAC Contracting to discuss an evaluation of your heating system and air distribution. Our family-run company has served Greater Pittsburgh for over 30 years, helping homeowners make informed decisions about comfort and efficiency. We can help identify whether duct repairs, insulation improvements, or another heating issue deserves attention.