Acoustic Isolation of Cinemas

Cinema soundproofing prevents the audience from being distracted by outside noise and stops noise from the cinema spreading to neighbouring screens or public areas. Cinemas are often in built-up areas, so noise from trainlines, traffic, or building work can spoil the cinematic experience for the audience. Likewise, noise from the films should be prevented from escaping the cinema and disturbing people in other screens or other parts of the building.

Whether at a public multiplex or in a home cinema room, noise reduces enjoyment, disconnecting the audience from the storyline and shattering the immersive experience.

Cinemas typically require high levels of isolation to prevent noise leaking between screens and public areas. Sound absorption or acoustic panels alone are usually insufficient. While high frequency vibration can be absorbed, low frequency vibration travels through the building’s structure and can then re-radiate as sound somewhere else.

For example, the rumble of an explosion from an action film showing in one screen can ruin the experience of the audience during a quiet moment in another. Explosions are particularly likely to be heard because these low frequency vibrations travel further than high frequencies, which are more easily absorbed, as mentioned above.

High levels of attenuation are crucial to ensure the film experience is uninterrupted. Correct isolation should therefore introduce a barrier to prevent vibration spreading too far.

Cinema isolation is a little different to isolating other rooms or buildings, partly due to the seating and walkways and partly because of the prevalence of low frequency vibrations from the subwoofers mentioned above.

Special Acoustic Considerations for Cinemas

In a cinema, acoustic isolation must encompass the whole area subject to noise from films, including the seating and entrance walkway.

Acoustically separating the entire screen room from the rest of the building structure requires a floating floor design, which must interface with the walls and raked seating. Depending on what is already in place, engineers can determine the most appropriate solution, typically mounting a concrete floating floor on spring or rubber isolators.

Mason UK has worked with specialist concrete contractors to design and construct isolated tiered seating, as well as walls and ceiling treatments to meet cinema acoustic requirements. Our engineers have years of experience choosing the best materials for isolators in a range of applications.

The ‘Box in Box’ Isolation Method

For cinemas, a box-in-box design offers the best acoustic isolation, because it tackles a broad range of vibration frequencies.

A box-in-box design is where an internal room is built within the existing structure. This internal box is totally isolated acoustically from the surrounding building. This is achieved via a combination of airgaps, LDS rubber and/or springs, depending upon loads and natural frequencies. These are built into the floors, walls and ceilings and ensure that noise from one screen room cannot pass into another.

Box-in-box Construction Elements:

We have broken up the description of box-in-box construction into 3 main areas listed below.

Acoustic Floating Floors

Floating floors are available in a range of materials, including wood and concrete, and use different isolators such as spring or rubber. Using the Mason jack-up floating floor system, these spring or rubber mounts raise the floating floor from the structural slab beneath creating an air gap that reduces the transmission of vibration in the same way that double glazing reduces the transmission of heat.

Acoustically Isolated Walls

The walls are then built up along the edges of this flooring. They are attached to the existing structure via acoustic wall ties and sway braces (type DNSB-A sway brace for stud walls, and DNSB-BM brace for block work walls). At the head of the wall a resilient angle is often required (we recommend the AB-716 head restraint) to provide an acoustic seal. More information on these can be found at the bottom of this page or on our ‘Isolated Walls’ page.

Suspended Ceilings

The final part is a suspended ceiling. Acoustic ceilings are suspended on drop rods from the concrete soffit or timber joists. Usually, we would recommend our HDQF hangers, although Mason UK has a large range of rubber and spring hangers available, the selection of which depends on the ceiling construction and the nature of the vibration.

The HDQF has been designed to easily clip onto the common MF ceiling grid ceiling system. A more detailed description of this product is available at the bottom of the screen. To view the other hanger types available please visit the products and solutions page.

Get in touch

Mason UK has worked on numerous cinema projects, isolating multiple screens. To view a selection of cinema projects, please visit the case studies page. We can provide suitable products and design expertise to help with these aspects, recognising that each job is unique and providing the perfect acoustic isolation solution.

Should you have any questions, require advice or wish to make an order, please contact our friendly engineers.