EN 771-3 : 2011+A1 : Specification for masonry units - Part 3 : Aggregate concrete masonry units (Dense and lightweight aggregates).

This standard specifies the characteristics and performance requirements of masonry units made from normal-weight, lightweight or combined concrete aggregates, primarily intended for use in common, facing or exposed masonry, whether load-bearing or non-load-bearing, in buildings and civil engineering works. Suitable for all types of walls, including single-leaf walls, external chimney walls, cavity walls, partitions, retaining walls and basements, these units may provide fire protection, thermal and acoustic insulation, and sound absorption. The standard also covers non-rectangular, special-purpose and accessory units. In particular, it defines strength, density and dimensional accuracy, provides for the assessment and verification of constancy of performance (AVCP) of the product in accordance with its provisions, and specifies marking requirements. It does not standardize unit dimensions, manufacturing dimensions or the angles of specially shaped units. It excludes storey-height panels, flue liners, damp-proof course units, and units incorporating thermal insulation bonded to faces that may be exposed to fire.