Changes to the rules that govern the installation of precast concrete flooring will allow the benefits of H+H’s innovative Thin-Joint System to be realised in the construction of more apartment blocks, care homes and other buildings with precast concrete floors.
Until recently, landing precast concrete floor systems on to cavity wall constructions has required the outer masonry leaf to be in position, unless the inner leaf of block work is a minimum of 190mm thick. However now, after recent amendments to the Code of Practice by the Precast Flooring Federation, when using H+H Thin Joint system, the thickness of the cavity wall inner leaf can be reduced to only 140mm without the need to back it up with the external brickwork. A maximum of two floors may be installed at a time in this manner, to a maximum of four storeys overall.
The Thin-Joint system uses large format, accurately dimensioned, aircrete blocks and quick drying Celfix Mortar as part of a super-quick construction solution. The benefits of using the system are maximised when the inner leaf of an external cavity wall is built independent of the outer skin.
H+H’s Thin-Joint system allows the inner leaf of a cavity wall to be constructed first, faster and to better quality than traditional brick/block cavity construction. This allows separating floors, roof covering and even windows to be installed early in the build-programme; as a result, follow-on trades can start work sooner in a weather-proof environment. Because the Thin-Joint system takes the external brick wall off the critical path, it allows the wall’s brickwork outer-skin to be constructed later in the construction programme.
Contractor, The Highwood Group used H+H’s Thin-Joint system of 140mm wide, 610mm long, and 270mm high Jumbo Plus blocks for the load-bearing inner leaf of the cavity wall of the three-storey Parker Meadows Care Home. Thin-Joint was used to meet a tight construction programme with the hollow core precast concrete floor planks located directly onto the 140mm wide Thin-Joint inner skin. Stephen Matthews, project manager at The Highwood Group said: “Using the Thin-Joint system enabled us to take the construction of the external brickwork outer skin off the critical path, which was a bonus in terms of the overall construction programme.”