The first course of blockwork is laid onto the reinforced concrete slab. A DPC is placed adjacent to the perimeter insulation which is formed by the upstand of the sub-foundation insulation.
This first course is laid on a bed of sand and cement mortar to level out any imperfections in the raft. The vertical joints are bonded with Thinset mortar to ensure the bond is kept in subsequent courses and also adds a little rigidity to the blockwork.
The blocks are manufactured from a material which would normally go to landfill, this is added to a little cement to act as a binder and aluminium which expands in the mix to produce a concrete block with millions of air bubbles. This process is not unique but we have found a way of producing the block to give the best thermal value of any aircrete block on the market with a thermal conductivity of 0.07W/mK almost 35% better than the standard 0.11W/mK.
The 190 wide blocks are laid with Thinset mortar whichbonds the blocks together with a 2mm joint. This is possible because the blocks are manufactured to a tolerance of ±1mm. The mortar is applied with a notched trowel which delivers a pre-determined amount of mortar to the block. This allows a fast but more importantly precise method of building, minimising thermal bridging and ensuring airtightness as the wall is built.
