BX 25 NZ (25x20x25) load-bearing seismic or curtain walling masonry made with Leca Bioclima Sismico Termoisolante expanded clay blocks, laid with traditional mortar, with "coat" insulation on the outside (λ=0.036 W/mK) and finishing plasters. Also available in 30 and 35 cm thicknesses with higher performance characteristics.