An introduction to open web joists
In This Series
Open Web Joists are parallel chord trusses made from strength-graded timber joined together with either timber of metal webs. The resulting joist combines the lightness of timber with the structural qualities of the metal webs or plates, to produce a factory made precision-engineered component that is lightweight, strong and versatile.
This data sheet from the Trussed Rafter Association explains the benefits of open web joists which make them ideally suited to modern methods of construction. It also details how, despite being designed for flooring, Open Web Joists can be used for a variety of other commercial, domestic and industrial structural applications.
- Practical benefits
- Support details
- Technical Approvals
- Site handling & storage
- Do's and Dont's
Widely used for a range of building types, trussed rafters are an economical, versatile and straightforward solution to providing a roof over a building.
Trussed rafters are individually designed prefabricated structural components made from strength-graded timber members of the same thickness, joined together with punched metal plate connectors....
There are a number of ways to design and construct pitched roofs using timber. Traditionally, builders constructed them on site, cutting and fitting each piece to its neighbours. Following the Second World War, various forms of prefabricated truss were developed, with the intermediate rafters and purlins cut and fitted on...
This information sheet is an extrapolation of the standard bracing requirements given in BS 5268-3 extended to cover 'Room in the Roof' trussed rafters. All the information given here should be read in conjunction with the requirements of that standard.
- Why brace trussed rafter roofs?
- Bracing responsibility ...