Frequently asked questions

Lightweight concrete: cement and virgin expanded polystyrene beads (Politerm® Blu and Blu Fein, 3 to 6 mm) treated to bond with cement. From the 450 density upwards the mix also contains graded aggregates. The blocks are solid, vibro-compressed, category II and CE-marked to EN 771-3.

It depends on density and thickness. With the 300 density and 1.5 cm of traditional plaster on each side: 20 cm gives U 0.358 W/m²K, 33 cm U 0.227 W/m²K and 50 cm U 0.153 W/m²K. Compliance with local energy requirements must be checked on the project.

The 900 and 1200 kg/m³ densities, which have an average compressive strength of 5.5 N/mm². The data sheets indicate them for load-bearing masonry from a thickness of 15 cm. Densities from 300 to 750 are for infill walls, partitions and lining walls.

The first course on cement mortar, for levelling; all following courses with Malta Block 600, the EN 998-2 class M2.5 thermal mortar with λ 0.158 W/mK, which prevents the joint from becoming a thermal bridge.

The first number is the thickness in centimetres (33 cm), the second the density in kg/m³ (300). The range has 6 densities (300, 450, 600, 750, 900, 1200) and 8 thicknesses (6, 10, 15, 20, 25, 33, 40, 50 cm); the 1200 density goes up to 40 cm, for 47 items in total.

All densities are Euroclass A2-s1,d0 for reaction to fire. For fire resistance the ESB catalogue gives EI 60 from 80 mm, EI 90 from 100 mm, EI 120 from 150 mm, EI 180 from 200 mm and EI 240 from 240 mm, for walls up to 4 m high.

The calculated sound reduction index Rw ranges from 38 dB (300 density, 6 cm) to 56 dB (750, 900 and 1200 densities in the largest thicknesses), for a wall plastered on both sides. These are calculated values, not laboratory measurements.

5 blocks with the 6 cm thickness (1 m long), 10 with the 50 cm-long blocks and 20 with the 25 cm-long blocks, which are the formats of the heavier densities in the larger thicknesses.

The ESB catalogue indicates about 65 m² of wall a day with the 33 cm block, as a guide. Actual times depend on the site.

Yes. They are cut with angle grinders, circular saws and band saws, such as the ESB.ATHENA.515 saw; chases for services are made with wall chasers and sealed with Malta Block 600.

Cement plaster, fibre-reinforced cement plaster, gypsum plaster (inside only), Edilteco’s Isolteco® thermal plaster (recommended outside) and reinforced skim coats such as Ecap® ADP, following the installation manual.

One 50-litre bag lays about 5 m² of masonry. Each bag is mixed with 15–18 litres of water; the mortar is applied between +5 °C and +35 °C.

With reinforced lintels for openings up to 3.00 m, bearing 25 cm on each side. Sub-frames and hinges are fixed with cement mortar or chemical resin.