Properly installed exterior fans run at about 35 dB at 3 feet, quieter than a refrigerator. Interior fans installed in attics or garages are inaudible inside the living space.
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Sound rating depends on fan model and mounting. The most common Cincinnati-installed fan, Radonaway RP145, is rated 50-55 dBA at 1 meter on the manufacturer's spec sheet. Mounted outside in a vented enclosure on the wall, that drops to roughly 35 dBA at 3 feet by the time it reaches a bedroom window. For comparison, a typical refrigerator runs 40-50 dBA. Exterior wall mounting in a sealed weather-rated cabinet is the Cincinnati standard and is what the install teams use by default. Interior mounting (in an attic chase) is quieter still but requires conditioned-space access and is less common in older Cincinnati housing where the chase may not exist. If the home has a bedroom directly adjacent to the planned exterior mount location, our team will reroute or upgrade the fan to a quieter model (Festa AMG250 at ~30 dBA) at install time. Cincinnati installation note: most older Hyde Park, Norwood, and Mariemont homes have brick or stone exterior walls that reflect fan noise differently than newer vinyl-clad homes. The acoustic profile differs slightly, and Our Cincinnati installers position the exterior fan enclosure to minimize reflection toward bedroom windows. Test the perceived noise with the homeowner during install before final mounting if anyone is sound-sensitive.