Designing for NC-15

NC-15 is a noise criterion rating. It describes a room so quiet that the loudest thing in it is usually the person sitting there. A recording studio is typically rated NC-15 to NC-20. A quiet bedroom at night is around NC-25.

What makes the noise

In a bath it is almost never the guests. It is water: pumps, inlets and overflow channels. At Sassalda the spring enters each pool below the surface, the pumps sit in a separate chamber behind a double wall, and the overflow runs into a channel lined with gravel so it drains without splashing.

What we ask of guests

Speech is allowed in the changing rooms and on the terrace. In the pool halls we ask for silence, and during the last water session the whole house is quiet from 20:30. Phones stay in the lockers. There is no music anywhere, at any time.