How much noise does an acoustic fence reduce?

Acoustic fences typically reduce noise by 15-28 dB depending on the panel mass and construction. A standard acoustic panel (12 kg/m²) provides around 15 dB reduction, while premium panels (25 kg/m²) can achieve 25 dB or more. For reference, a 10 dB reduction sounds roughly half as loud to the human ear.

How does fence height affect noise reduction?

Fence height is critical for acoustic performance. The fence must break the line of sight between the noise source and the listener to be effective. Taller fences provide better diffraction attenuation — every doubling of effective height above the line of sight adds approximately 5 dB of reduction. Most acoustic fences are 2-3m tall.

What makes an acoustic fence different from a standard fence?

Acoustic fences use dense, tongue-and-groove or overlapping boards with no gaps. The panels are typically 20-40mm thick with a mass of 12-30 kg/m². Standard fence panels have gaps and lightweight construction that allow sound to pass through. Acoustic panels may include mass-loaded vinyl or mineral wool cores for extra performance.

Do I need planning permission for an acoustic fence?

In England, fences up to 2m do not usually require planning permission unless on a highway boundary (1m limit). For acoustic fences over 2m, planning permission is typically required. Some local authorities have specific policies on noise barriers. If the fence is part of a planning condition, you must comply with the specified acoustic requirements.

Where should an acoustic fence be positioned for best effect?

For maximum noise reduction, position the acoustic fence as close to the noise source as possible, or as close to the receiver as possible. The worst position is midway between the two. The fence should extend at least 5 times its height beyond the area to be protected, to prevent noise flanking around the ends.

TradeCalculator.co.uk

Acoustic Fence Calculator

Calculate acoustic barrier panels and noise reduction based on panel mass, height and noise source geometry. UK specifications and dB ratings.

Fence Length

Total run of acoustic barrier

Fence Height

Taller = better noise reduction

Panel TypeHigher mass = more dB reduction

Noise Source Height

Height of noise source above ground

Distance to Noise Source

From fence to noise source

Distance to Receiver

From fence to listener position

Price Per Panel (optional)

Your supplier's price per acoustic panel

Price Per Post (optional)

How We Calculate This

This calculator estimates acoustic fence panels needed and the noise reduction achievable based on panel mass (surface density) and barrier geometry. It uses the mass law principle for sound transmission loss.

The formula

Panels = Fence length ÷ Panel width (rounded up)
dB reduction ≈ 20 × log10(mass/m²) (mass law approximation)
Path difference = A + B - d (Maekawa barrier diffraction)

The mass law states that doubling the surface mass of a barrier adds approximately 6 dB of sound reduction. A 25 kg/m² panel will reduce noise by roughly 25 dB at mid-frequencies, which sounds about 80% quieter to the human ear.