Dense Concrete Blocks

Dense Concrete Block

Dense concrete blocks are usually made from cement, fine aggregate and coarse aggregate. They can be produced in a range of crushing strengths and, nowadays, tend to be used for loadbearing partitions, foundations and, possibly, party walls. They generally have poor thermal insulation and readily absorb water. However, 20 years ago they were common in the internal leaf of cavity walls (when insulation requirements were less onerous) and nowadays they can also be used to form the external leaf providing some form of cladding or render is provided. Dense blocks should be laid in mortars of average strength; 1:1:6 or 1:2:9 (or their equivalent). Stronger mortars may limit movement and may cause cracking in the blocks rather than the joints. Weaker mixes may compress under loading. Stronger mortars are sometimes specified below ground level. Picture below dense blocks forming part of the substructure. The lining is proud of the block work to receive the plaster work. The joint between the two will then be covered with an architrave.

Wall made by dense concrete block