a) hollow bricks for construction walls
b) foundation wall blocks
c) blocks for partition walls
d) lintel fittings U – for use over holes to 3,3 m span
e) Teriva ceiling blocks (span of ceilings to 7.2 m)
Expanded clay is a light ceramic aggregate, obtained by firing the fusible, swellable clays, without admixture with any harmful substances. LECA is fired in rotary kilns at a temperature of 1100-1300 ° C, after the clay was mechanically crushed into small fractions. After burning out, LECA grains take a spherical shape, and on their surface a characteristic brick-colored sintered coating is formed in thickness 0,5-1 mm. Sorted LECA is available in the following fractions:
– fraction 0-4 mm – (volumetric weight 425-575 kg/m³),
– fraction 2-4 mm (volumetric weight 332-449 kg/m³),
– fraction 4-8 mm – (volumetric weight 280-380 kg/m³),
– fraction 4-10 mm (volumetric weight 270-370 kg / m³),
– fraction 8-20 mm (volumetric weight-230-310 kg / m³)
– fraction 10-20 mm (volumetric weight 230-310 kg / m³).
Advantages of expanded clay:
• It is characterized by a low coefficient of thermal conductivity which makes it, that it can be used to make elements with high insulation – LECA wall with a thickness 15 cm insulates as much as a brick wall in thickness 0,5 m.
• Accumulates heat well, thanks to which the expanded clay wall can keep heat longer than the walls made of other building materials.
• It is four times lighter than natural aggregates, and despite its lightness (the weight of the expanded clay is 0,65-0,30 kg / dm3) it is very resistant to compression.
• It is non-flammable – LECA construction elements have the highest fire resistance class (class A).
• LECA structure provides the walls with high sound absorption, which translates into high comfort of living.