Cetris

Cement bonded particleboards CETRIS^® is also used for exterior cladding for its high weather, fire and mechanical damage resistance. In addition to building cladding the CETRIS^® board may also be used as fill of staircase railings, balconies, terraces, loggias etc.

Safety and usability for railing and balcony, terrace and loggia fills are assessed pursuant to ČSN 74 3305 standard "Protective Railings". The critical test is review of railing fill reliability by impact stress test. This test requires resistance of railing fill to soft impact with the impact energy of up to 250 J.

This impact test is to prove safety of the railing in case of hitting by a person. A test sample corresponding to real implementation is exposed to effects of impact of a test object falling with the required energy in perpendicular direction towards the fill surface. The softness of the impact is assured with a bag filled with glass beads with the diameter of 3 mm and total weight of 50 kg. The impact point is selected according to the weakest point of the fill - mostly the fill centre. After the impact test the fill condition is assessed – the impact may not result in a hole letting through a ball with the diameter of 76 mm, or in a tear extending as far as the edge of the fill. On the basis of these tests the minimum required thickness of the CETRIS^® cement bonded particleboards is 14 mm, with the fixation and anchoring methods described in the respective technical data sheets.

The cement bonded particleboards designed for these applications are CETRIS^® FINISH. CETRIS^® FINISH boards are treated on the face and on the edges with a primer and a top coat (shade according to RAL, NCS – consult the colour shade suitability with the manufacturer). The reverse side of CETRIS^® FINISH boards may be treated with a white primer on customer request. Such surface finish does not offer, of course, identical covering power as on the face. In order to achieve the same look we recommend the back side to be treated with a final coat of paint directly at the construction site.