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Performance Rated I-Joists

I-joists are ‘I’ shaped engineered wood structural members designed for use in residential and non-residential construction.  The product is prefabricated using sawn or structural composite lumber flanges and OSB webs, bonded together with exterior type adhesives.

American producers mainly supply I-joists in lengths up to 60 feet, and the most common depths, in inches, are 9-1/2, 11-7/8, 14 and 16.  As each manufacturer produces specific technical material for their own product, here’s APA’s  construction guide for I-joists  produced by their member mills.

There is no harmonised standard for I-joists so manufacturers apply for a European Technical Assessment (ETA) to measure the product against specific test requirements. The European Assessment Document (EAD) is the official means of enabling a performance assessment to be made so that products can be CE approved (in the EU). Download the full EAD for I-joists.

A UK TAD (UK Technical Assessment Document) is pending and is likely to be based on the EU EAD.