How loud is a radon mitigation system?
Short answer: Modern radon fans are very quiet — typically 30 to 45 decibels at the fan, which is quieter than a refrigerator. Inside the home, you usually can't hear it at all unless you're directly under the attic-mounted fan.
Radon fans have come a long way. The current generation (Radonaway RP145, RP140, Festa AMG Junior, Festa SoLow) operate at 30 to 45 decibels at the fan housing — quieter than a refrigerator, comparable to a soft whisper.
Inside the home, with the fan installed in the attic or on an exterior wall, most Iowa City homeowners can't hear it at all. The vent pipe carries some air-rush noise but it's similar to a passive HVAC return.
A few things can make a system louder than it should be:
- Wrong fan size — an oversized fan running near max draw is louder than a properly-sized one
- Loose pipe straps — pipe vibration against framing transmits noise into walls
- Fan mounted on shared framing — if the fan housing is bolted directly to a stud that runs into a bedroom wall, you'll hear it
All of those are install errors, not fan limitations. A properly installed system in Iowa City should be effectively silent inside the home.