When do you need a radon muffler

Radon fans run continuously through all types of weather.  They’re workhorses and they typically last quite a long time–often over a decade.  When you have a radon fan running all the time, you want to make sure it’s quiet and unobtrusive.  What happens when your radon fan is so noisy it keeps you up at night and you can’t sleep?  Or your radon fan is annoying your neighbors?  You want a radon fan that is quiet and lets you sleep.  Let’s go over how to make that happen.

Right fan for the right home

Very few states require radon contractors to be licensed or trained in any way.  States that do have regulations, often have little enforcement.  It’s a shame, but it’s the sad reality of modern radon mitigation: many, many so-called professionals just aren’t educated enough to do their jobs effectively.  When a contractor isn’t trained for radon, or they naively underestimate the difficulty of radon mitigation, they typically go overboard in their radon fan sizing.  They do what we call “poking and hoping”.

Real radon professionals, those that under-go continuous education on pressure field testing (PFE) and diagnostics, understand how to size a radon fan.  However, even these professionals are not always asked to use their expertise (i.e. paid for it).  If you’ve read our home buyers guide for radon, you’ll note that many radon systems are installed during the real estate transaction and paid for by the seller.  This incentivizes choosing the lowest bidder or not paying a qualified contractor to do the extra diagnosis work to really hone in the fan selection to be the most energy efficient.  I hear this every day on calls with homeowners: “why would I pay more?  I’m selling the house”

The best solution for radon fan noise is always asking a radon professional—trained in “PFE diagnostics” and fan sizing (est. less than 10% of contractors)—to do the job for you and to pay them accordingly for their time.

Another car analogy

The pros that poke and hope remind me of bad car salesmen.  It’s the guy trying to sell a lifted pick up truck to everyone that walks through the door because that truck can do it all.  They assume that bigger is better.  This is not true for radon.  Bigger radon fans are not always better but they are always louder.

Right fan: still noisy

If you’re certain you have the right fan but the noise is still troublesome, here are some diagnostics you can do to determine if a radon exhaust muffler will solve your issue.

Is the noise bothering the occupants of the home or the neighbors?  Interior fan noise is the most common fan noise and it typically not solved by a muffler.  Interior noise is often the result of system design; poor fan placement and fan vibration making it’s way through building materials to the inside of the home.  You hear your bathroom fan when you turn it on right?  Same with a radon fan, so try to keep it away from bedrooms and sleeping areas.  The vibration from the fan motor and impeller will reverberate through the home.  Use vibration isolating materials and never anchor a radon fan to the home.  The only things that should touch a radon fan are the fan couplers or “boots”, and the fan’s power cord.  Do not use fan brackets.  Properly installed and anchored PVC with radon fan couplers is plenty to hold the fan up.  Choose LDVI radon specific fan couplers to reduce interior noise.  LDVI stands for “low durometer vibration isolating”.  We call them “squishies”.

If the fan noise is bothering your neighbors or ruining your outdoor activities, then maybe it’s time to try a muffler.  Try these things first: can you change the fan location?  Are you certain the exhaust meets code?   Fan exhausts should be straight up in the air and above roofline.  If your exhaust is at ground level or contains a U bend, get a full system inspection immediately.  Those are RED FLAGS.  They can also increase noise.

If you can’t move the fan exhaust, can you tune the fan down?  EC radon fans use less energy and can be dynamically tuned to fit the home’s needs: they’re also typically quieter than their AC counterparts

If you need a big fan AND you can’t change the system design, then it may be time to use a radon muffler.  At PDS we offer several sizes and types be sure you choose the right PVC fit.  View them all here

Proper fan size saves money

You may find me a stickler for radon fan sizing; however it’s not just the right thing to do, it’s the smart thing to do.  Read how radon system design and fan choice actually pays for itself over the life of the system here.  Do the right thing and save money?  How lucky are we?

Thanks for reading!  If you’re building a new home and want the quietest system, use our radon mat