SILENCIO • An eco-friendly, sustainable sound attenuator for mechanical ventilation systems

The SILENCIO project gave rise to ehho®: a sound attenuator for mechanical ventilation systems.

The ehho® sound attenuator was developed to tackle nuisance noise in homes, while providing an eco-friendly and sustainable solution.

A simple specification, then, but it was a real technical challenge to design a financially viable product made completely of textiles (at least 70% of which were recycled) – to make it easier to recycle at the end of its life – while providing exceptional acoustic performance. On top of that, it had to be made in France.


Homes are increasingly well-insulated from outside noise. At the same time, inhabitants are becoming much more sensitive to noise originating inside their home.

New design trends, with an open or semi-open kitchen that forms part of the living area, as well as new energy efficiency standards in France that require the installation of a mechanical ventilation heat recovery system, mean inhabitants are increasingly disturbed by airflow-related noises caused by the ventilation system.

Success story

The ehho® mechanical ventilation system sound attenuator is made in the Hauts-de-France region and has been commercialised since March 2019 by WECOSTA.

  • creation of the ehho® trademark
  • eight jobs created or saved
  • within 5 years, turnover of €1,000,000 generated (of which 10% in export markets)


Key info

Project type: French agency for the environment and energy management/Eco TLS project

Start date: 2016

Project duration: three years

Learn more at

retour en haut