town & country planning - sound absorbing walls


Khufu type sound absorbing walls can be applied alongside roadways, railroads and industrial sites.

Technical Characteristics

The concrete wall, conforming to CE EN 14388, is corrosion and weather resistant, made of non-combustible material and consists of one or more elements. The elements have a load-bearing concrete structure on the back and an absorbent open-pore surface structure in lightweight concrete on the front. The elements must rest on a concrete plinth with a thickness to match the load-bearing concrete wall.

Concrete quality: C 40/50

Environment class: EE4

Environmental class: XC4 – XF4

The sound-absorbing porous layer consists of a linear, vertical design pattern with trapezoidal beams with a total thickness of ± 180 mm. It consists of cementitious expanded clay granules with a grain size varying between 1 and 5 mm. Due to its cementitious nature, the profile of the absorbent part is immutable and not deformable. A wave pattern provides the optimal absorption of both road and rail traffic sound frequencies.


Acoustic properties

The sound absorption DLα of the sound barrier is 12 dB for the traffic spectrum and 14 dB for the TGV spectrum according to NBN EN 1793-1

The DLR airborne sound insulation is 42 dB (highest quality category airborne sound insulation B4, insulation according to NBN EN 1793-2).

The measurement results for absorption “in situ” according to NBN EN 1793-5 for the “panel” DLRI are always > 5 dB.

The measurement results for airborne sound insulation ‘in situ’ according to NBN EN 1793-6 are: DLSI,E (center of panel) 65 dB, DLSI,P (support post): 48 dB.

architectural characteristics

The front of the wall has a specific shape, designed for optimal sound absorption. The wall can be made in different colors by adding color pigments (green, brown, ochre, etc.), which allows one to obtain variety in the appearance. The profiled open-pore shape on the front makes the wall absolutely unattractive to graffiti. Above, an additional 3D structure can be applied while maintaining performance.


The elements/walls rest on a concrete plinth with a thickness adapted to the load-bearing part of the sound wall in concrete. The attachment of the elements to the vertical support profiles is done by means of a rail system, already incorporated in the back of the sound wall. The soundproof walls, as well as the skirting boards, are therefore placed in front of the support profiles in order to limit as much as possible acoustic leakage at the level of the profiles.