03 · Acoustic construction

Acoustic windows

Studios, control rooms and observation rooms need sightlines through walls built to stop sound. That is a glazing assembly, designed with the wall it sits in.

Also in openings

Performance comes from the same three things as a wall — mass, separation and sealing. In glazing that means panes of differing thickness, an air gap of useful depth, frames isolated from one another where the wall is a double structure, and reveals that are sealed and absorbent.

How they are built

PanesTwo or more, deliberately different in thickness so they do not resonate together.
CavitySized for the isolation required rather than for the frame that was available.
FramesIsolated from each other where the wall is a double leaf; sealed to each structure separately.
RevealLined with absorption inside the cavity, which is where a great deal of the performance comes from.
Glass typeLaminated where mass, safety or damping is wanted.
SealingContinuous, both sides, checked before the finishes go on.

Sightlines first

We set the window from the seated eye position on both sides — angle, height and size — before the construction is designed around it. In a control room that means the engineer sees the performer without turning; in an observation room it means the whole test area is visible. Where reflections in the glass would be a nuisance, panes can be raked so they reflect towards an absorbent surface rather than back at the listener.

Where they are used

  • Between a control room and a live room in a studio.
  • Between a viewing gallery and a test chamber or laboratory.
  • Between a plant room and an office or reception.
  • In facades, where traffic or railway noise is the problem.
  • In interview, consultation and security rooms where speech privacy matters.

Glazing performs as an assembly. A pane specified on its own tells you very little about the finished opening.

What we need to quote

  • Opening size and the wall construction it sits in.
  • What is on each side, and the separation required.
  • Whether the wall is a single or double structure.
  • Eye positions and sightlines the window has to serve.
  • Any fire, safety or security requirement on the glazing.

Tell us the room

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