On Monday, 4 November 2019 23:04:46 UTC, wrote:

The never-ending list of jobs has now reached the point of needing an
extractor fan for the new loo. The requirements are straightforward:
effective, wall-mounted, quiet, no timer.

That's easy: avoid a 4"er. Yes they're cheap, but don't shift much & are the noisiest. Also look at specs, noise varies greatly. And in some cases you can just use a vent/flap, no fan required.


NT