Non-metallic building materials, namely, hydraulic curing or chemical curing flowable building materials, namely, light weight concrete; non-metallic building materials, namely, hydraulic or chemical cured building materials, namely, building blocks; non-metallic prefabricated natural and artificial structural elements for construction purposes, namely, wall units, namely, non-metal partitions for building; ceiling components, namely, panels, not of metal, roof elements, namely, non-metal roofing or bottom plates for connecting pipes used in heating and air conditioning floor, wall or ceiling systems and installations; non-metallic prefabricated structural elements, namely, precast concrete and precast porous concrete; inorganic binders, namely, hydraulic binders namely, hydraulic cements for the manufacture of building materials and for construction purposes; natural and artificial aggregates composed of metakaolin, diatomite, perlite, sand, limestone, or chalk or mixtures thereof for use in the preparation of building materials and for construction purposes; non-metal paving materials, namely, mortar, porous concrete compositions and concrete compositions

Building construction; erecting of manufacturing plants; repair or maintenance of machinery for the manufacture of building materials; rental of building machinery

Structural engineering