03 · Acoustic construction

Air movement and conditioning acoustics

Ventilation is what a sealed room needs and what most often spoils it. Air brings noise in along the ducts, and the plant makes its own.

Everything in this section

Once a room is isolated, the ductwork is usually the loudest remaining path — for plant noise arriving along it, and for conversations passing between two rooms served by the same branch. It is also the last thing considered, which is why it is so often the reason a finished room misses its target.

Three problems, one system

Plant noiseFans and units heard along the supply and return — solved with attenuators, lined duct and plenums.
Regenerated noiseMade locally by air moving too fast at bends, dampers and grilles — solved with velocity limits and better geometry.
CrosstalkSpeech passing between rooms through a shared branch — solved with crosstalk attenuators and duct routing.
BreakoutNoise radiating through the duct wall itself as it passes over a quiet room — solved with lagging or rerouting.
Structure-bornePlant vibration entering the building through its bases and duct supports — solved with isolation.

What we handle

Designed with the mechanical engineer

Attenuation costs pressure, and pressure costs fan power and makes its own noise. The acoustic and mechanical designs have to be done together — silencer type, duct velocity, branch layout and plant location are one decision, not two. Where the numbers do not reconcile, the answer is usually a larger duct rather than a deeper silencer.

A room can only be as quiet as the air it breathes.

Tell us the room

Send dimensions and intended use. You get back an indicative acoustic treatment, a systems outline and a budget range.