Air leaks in HVAC ducts might not seem like a big deal at first, but they can have a surprising impact on your home’s comfort and energy bills. If your HVAC system is working overtime just to keep your house comfortable, leaky ducts could be the culprit. Sealing those leaks is easier than you might think and can make a noticeable difference in your home’s efficiency and airflow.
First, let’s talk about spotting the leaks. If your energy bills are higher than usual or some rooms in your home feel hotter or colder than others, your ducts might be leaking air. You can also do a little detective work by looking for visible gaps, loose connections, or tears in the ductwork. If you have access to your attic or basement, these areas are common trouble spots since ducts there are often uninsulated and exposed.
Once you’ve identified where the leaks might be, it’s time to get to work. The good news is that you don’t need to be an HVAC pro to seal ducts. One of the best tools for the job is mastic sealant. It’s a sticky, paint-like substance designed specifically for ducts. You’ll want to apply it generously to any seams, gaps, or holes you find. It takes a little time to dry, but it creates a durable, airtight seal that will hold up for years. For larger gaps, you can use metal tape—just make sure it’s not the standard duct tape you find in your junk drawer, which isn’t rated for long-term HVAC use.
If you’re dealing with flexible ductwork, check for loose connections where ducts meet vents, the air handler, or other sections of the system. Securing these connections with a combination of mastic and a metal clamp or zip tie can prevent air from escaping. While you’re at it, make sure the ducts are properly supported so they aren’t sagging, which can lead to more leaks down the road.
Insulation is another important step. If your ducts run through unconditioned spaces like attics or crawl spaces, wrapping them with duct insulation can help prevent energy loss and keep the air at the right temperature as it travels through your system. You’ll want to make sure the insulation is snug and secured with proper tape to avoid it slipping over time.
Once you’ve sealed and insulated your ducts, you should notice the difference almost immediately. Your HVAC system won’t have to work as hard, which means lower energy bills and more consistent temperatures throughout your home. It’s one of those small projects that can make a big impact, and it’s satisfying knowing you’ve taken control of your home’s energy efficiency.
If tackling this project feels a little overwhelming or you’re not sure where to start, calling in a professional can be a smart move. They’ll have the tools and expertise to find even the smallest leaks and ensure everything is sealed up properly. Whether you do it yourself or get some help, sealing air leaks is an investment in your home’s comfort and efficiency that’s well worth the effort.