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Historically, the vast majority of JJI-Joists have been used in domestic floors for houses and flats and, despite a significant increase in roof and wall application, this remains the case. 

The system is independent of the building construction method and can be used with traditional masonry construction or timber frame with equal ease, as well as being flexible enough to adapt to emerging construction methods like insulated concrete formwork, SIP panels and cross laminated timber (CLT).

Standard details exist to address common framing arrangements where airtightness, thermal and acoustic considerations must be met. In particular, there are several floor make-ups specifically aimed at meeting the stringent acoustic performance levels required for both intermediate and separating floors.  The pre-cut joists are quick to assemble onsite and the long lengths and dimensional stability improve performance and reduce differential movement. The 9mm OSB web material is easily cut and drilled to allow services of all common shapes and sizes to be routed within the floor depth. Where particularly large service holes are required, custom reinforcing metalwork is available in a range to match the joist sizes.

Our UK Technical Manual provides a comprehensive guide to the correct use of the JJI-Joists system and you can read it as a page turner here. Additionally if you register on the website you can download it as a pdf and hard copies are available from our Technical Support team. Additional advice can be obtained from our trained distributors or direct from the Timber Systems Division Technical Support team.

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