With the growing importance of durability and acoustic properties in the building industry there is more demand for a durable block that meets these requirements. Argex has developed the ClimaSono building block in response to this demand.

ClimaSono building blocks are composed of natural aggregates, cement and Argex expanded clay granulates. Clima is all about durability, thermal inertia … in short, everything related to energy efficiency. Sono refers to the sound properties of the blocks. Indeed, the importance of noise reduction and acoustic absorption within the building industry continues to rise. For example, meeting rooms, multipurpose rooms, sports halls, swimming pools, etc.

Several European research laboratories and universities have developed the Top Argex Building block, together with a few dozen manufacturers.


  • Supporting walls
  • Interior and dividing walls
  • Fire resistant walls
  • Acoustic walls


Our Climasono blocks are also available as glueable building blocks providing maximum efficiency.

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Providing thermal insulation for energy-efficient building

The ClimaSono building block has a greater thermal resistance (3 to 5 times better than traditional concrete) because the light Argex granulates have a porous internal structure which benefits thermal properties.

Sound-insulating and absorbent for optimal acoustic comfort

ClimaSono building blocks also score well when it comes to sound insulation. The sound isolation in a wall is measured with the sound reduction index Rw: this highlights the difference in sound level between the transmission space and reception space. ClimaSono building blocks insulate noise better than standard concrete blocks, despite having a mass that is significantly smaller.

For sports halls, swimming pools, multipurpose halls, and other such projects, noise absorption is of great importance. ClimaSono building blocks offer exceptional sound absorption thanks to their micro-porous cellular structure.

Durable and recyclable

Expanded clay is frost resistant. The material is used from the North to the South Pole and can resist extreme climatological conditions. ClimaSono building blocks boast an optimum level of porosity. This results in low levels of water absorption and frost resistance.

High pressure strength

A high pressure strength yet low density is an important advantage of the ClimaSono block and indeed all Topargex blocks. We are referring to pressure strengths of between 3 and 8 N/mm².


Heat and comfort are important factors in a building. Not to mention safety. Expanded clay is classified as an inflammable material according to Euro Norm A1. ClimaSono building blocks score significantly better than other systems (plasterboard, wooden structures, heavy concrete elements). The better fire-resistant values are thanks to low thermal conduction, together with a low expansion coefficient.


Expanded clay is used in the production of lightweight concrete blocks in order to combine a high compression strength and a low weight. When compared with traditional concrete blocks, with a density of over 2000 kg/m³, the ClimaSono building block has a low weight of max. 1400 kg/m³.

Variety of finishing options

Different finishing options are available for the ClimaSono building block: saw cut or axe cut, a rough or fine structure, etc. Furthermore, in some cases it is possible to choose one-sided or double-sided plastering.

Unique technical properties

Block type SOLID / HOLLOWSOLID (Group1); HOLLOW Group2) - EN 1996-1-1
Category of compressive strengthCategory I
Compressive class - fb (N/nm²)f3 to f8 - normalized average compressive strength(PTV 21-001)
measurements (cm)L: 29/39 B: 9/14/19 H: 14/19
Class size DeviationD1
Dry concrete Density (kg/m³)1250 to 1350 - average 1400 Max - value 90/90
Class dry volumic mass block type (kg/m³)9 cm block: 1.2 to 1.4 HOLLOW - 1.4 SOLID 14 cm block: 0.9 to 1.0 HOLLOW - 1.4 SOLID 19 cm blok: 0.9 HOLLOW - 1.4 SOLID (PTV 21-001)
Fire reaction classificationEuro class A1
Thermal conductivity coefficient λU,i (W/m.K)0.45 – 0.50