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Why Your Ductwork Is Noisy


Air ducts in your home can sometimes produce popping noises. If the noises are minor and occur only occasionally, there’s probably no need for concern. But if the noises are happening frequently enough to bother you, it’s probably time to have an HVAC contractor take a look at them.

In most cases, the noise coming from air ducts is produced by the introduction of air. Hot air makes ducts expand, while cold air makes them contract. Here are some possible reasons behind noisy ductwork.

Your Ducts Aren’t Round

Ducts can be round, rectangular or square. Round ducts handle changing temperatures and expansion the best and are therefore the most quiet. Square ducts are fairly noisy, while rectangular ducts are definitely the noisiest. It costs quite a bit of money to replace your square or rectangular ducts with round ones, so your heating repair expert will probably suggest an alternate solution, such as adjusting their location relative to surrounding surfaces or adding some insulation or padding.

The Metal Isn’t Thick Enough

A lower gauge rating means the metal used to manufacture your ducts is thicker, and therefore more capable of handling temperature changes. A higher gauge rating means the metal is thinner, so it expands and contracts more, making more noise. A gauge rating of 24-26 is ideal. If thin metal is what’s causing your popping noises, you’ll probably have to replace the ducts with a metal that has a lower gauge rating.

The Ducts Are Too Small

Size matters when it comes to ductwork. Small ducts expand more, which is why they usually make more noise than bigger ducts. Talk to your HVAC repair technician regarding this, as you may have to replace all of your ductwork. They’ll have the best recommendations on what will work for your home.

Noises coming from the ducts can have other causes as well, and some can be serious. It’s always a good idea to talk to a licensed technician to become better informed about the issue. Call John Stevenson Plumbing, Heating & Air Conditioning, Inc. today at (760) 276-6690 or fill out our contact form for a consultation.