What is an acoustic trickle vent?
An acoustic trickle vent is a ventilation grille with built-in sound attenuation, fitted in the fanlight, the glazing or the head of a window frame. In Dutch it is called a “susrooster”. It works like an ordinary trickle vent for natural supply of fresh air, but the air passes through a channel lined with sound-absorbing material. As a result far less traffic or aircraft noise comes in with it.
An acoustic trickle vent is more compact than a separate acoustic box above the frame. Manufacturers state the attenuation as Dn,e,w in dB, measured with the vent open. According to the data sheets of major manufacturers, acoustic vents reach roughly 30 to 40 dB; a standard vent damps much less. The better the attenuation, the larger and deeper the vent usually is.
In practice
- Choose on attenuation and airflow. The vent must supply enough air for the room. Airflow per metre is on the data sheet; check it for the length you fit.
- Check the fitting size. Glazing-mounted vents suit a set range of glass thicknesses. Measure your glazing before ordering.
- Use self-regulation. Many vents have a flap that closes in strong wind, which prevents draughts.
- Fit it high. At the top of the frame cold outside air mixes better with room air.
- Clean it. Clean the flap and mesh once or twice a year; dust and insects reduce airflow.
Common mistake: taping the vent shut because it feels draughty. The room then becomes damp and mould can follow. Fit a self-regulating vent instead.
Related terms
- Acoustic ventilation box
- Natural ventilation
- Sound insulation
- Fanlight
- Balanced ventilation
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