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Light Steel Oversail Walling Systems As an economic and efficient method of providing external walling systems for steel and concrete framed buildings, light steel external oversail walls are designed to resist wind loading on facades and to support their own weight and that of attached lightweight cladding materials. Ayrshire Metals
Typically constructed from the outside of the building, continuous walling ‘oversails’ the edge of the primary structure with studs being fixed via cleats maximising floor area. The components used in oversail are similar to those used for infill walling. However, there are some significant differences that must be considered in design and construction. Oversail walls are placed externally to the primary structural frame rather than between the floors as in the case of infill walls. Oversail walling systems are particularly suited to situations where cladding materials are sensitive to differing movement of the main frame. Adequate base support must be provided to accommodate vertical loading from the cladding. Openings in the building facade and a variety of cladding options can be accommodated. The continuous external walling system consists of vertical light steel C sections and bracket connections to fix them to the primary frame. Allowance for movement of the primary frame must be incorporated into the connections, usually by use of slotted connections. Dead weight of masonry cladding must be supported directly by the primary structure or foundations. However, light steel external walling systems can generally provide horizontal support against wind through the inclusion of a proprietary system of brick tie channels and brick ties positively fixed back to the stud. In addition to structural requirements, the design of both infill and oversail external walling systems must also consider fire resistance, condensation risk, weathertightness, thermal insulation and acoustic performance, and must allow for interfaces at windows, patio doors and balconies.
USEFUL DOCUMENTS SCI Publications including: P402 - LSF Residential Guide P302 - LSF Modular Residential P262 - Durability of Light Steel Framing in Residential Building P272 - Modular Architects Guide P348 - Building Design using Modules P367 - Energy efficient Housing using Light Steel Framing P370 - Sustainability of steel in housing P407 - BIM and 3D Modelling in Light Steel Construction P424 - Fire resistance of light steel framing P426 - Uninterrupted Height of Masonry Cladding to Light Steel Framing SCI Technical Information Sheets including: ED014 - Light Steel Module construction ED015 - Acoustic Performance ED016 - Fire Performance ED017 - Design and Installation of Light Steel External Wall Systems ED019 - Thermal Performance ED020 - Sustainability of light steel construction ED021 - Robustness ED022 - Durability
www.lsf-association.co.uk/library/lsfa-specification-and-engineering-guide/infill-and-oversail-systems
