Description of the Corehaus Limited Light Gauge Steel Frame Volumetric and Panelised Building System
CoreHaus Limited is a design and manufacturing company offering high quality prefabricated Light Gauge Steel (LGS) and hot rolled steel pods & LGS panelised cold-formed building system for residential buildings up to 2.5 storeys subject to geographical restrictions placed on the structural design element.
The system consists of a central pre-manufactured volumetric pod that houses a large proportion of the dwellings M&E plant as well as circulation space (such as stairways). The pod consists structurally of a Hot Rolled frame with LGS infill walls, with LGS floor and ceiling joists. The floors and ceiling Cassettes are manufactured in the factory along with the structural frame and consist of LGS. Any internal walls / partitions are delivered to site in stick form and built on site.
A unique advantage of the CoreHaus system is in its configurability and range of geometric possibilities in plan and elevation. The system is supplied up to waterproofing membranes only, with site specific cladding applied on a project by project basis.
Durability Assessment: minimum 60 years
Limits on scope
Maximum 2.5 storeys for loadbearing frames subject to structural analysis (with the incorporation of hot-rolled steelwork to achieve structural design parameters)
Bottom members in contact with foundations/sub-structure must be fully isolated from contact with moisture from the ground or external sources
Where lightweight gauge steel framing is used for ground floor construction, the ground below the floor must be sealed to prevent moisture entering the void, such as a membrane with 50mm oversite concrete, in accordance with the recommendations of Steel Construction Institute publication P262.
Where a lightweight gauge steel frame ground floor occurs over a void next to the ground, the void must be cross ventilated to a minimum standard of 1500mm2/linear metre, or 500mm2/m2 of floor area.
Masonry wall cladding cavities should be minimum 50mm and ventilated.
Conventional cladding, such as timber cladding, should have a minimum 25mm drained back-cavity, or as recommended by the manufacturer.
Rendered external thermal insulation systems and/or insulated brick slip cladding systems applied to steel-framed structures must have a minimum 15mm drained back-cavity OR, in the absence of a cavity (sheltered and moderate exposure zones only, cavity mandatory in severe and very severe exposure zones), any such application must be assessed to confirm that moisture accumulation would not exceed normal criteria for the avoidance of material degradation in the site specific climatic conditions likely to be experienced, evidenced by: a) Testing, e.g. MOAT 22 hygrothermal test or, b) ETAG 004 assessment, or c) Dynamic modelling, e.g., WUFI hygrothermal modelling (including 1% moisture penetration stress). The application of insulated cladding systems should be considered to minimise the risk of water entering the structure at vulnerable junctions, for example window jamb/sill junctions in accordance with the recommendations of the Steel Construction Institute publication P343.
Stainless steel fixings, such as channels for masonry retention systems, must be isolated from the galvanised steel to prevent bi-metallic corrosion where there is a risk of exposure to moisture.
Corehaus Limited must be contracted for the design, manufacture and supply of the structures.
A chartered structural engineer suitably experienced in the design of this type of structure must be sub-contracted for the structural analysis and design.