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JJI-Joists Just Keep Getting Better
James Jones & Sons Ltd Timber Systems Division, largest UK
producer of I-joists, has gained a TRADA Q Mark for significantly
increased engineering properties in their JJI-Joists. Improvements
in material sourcing have yielded timber with significantly better
mechanical properties, giving major advances in JJI-Joist strength and
stiffness: up to 35 % improvement in stiffness, and span gains of up
to 254 mm at 600 mm centres and 355 mm at 300 mm centres.
These improvements are further enhanced by an increase in flange
widths of the joists by 2 mm and 3 mm respectively, creating A+ and
B+ width products. James Jones reports that Code for Sustainable
Homes is creating new interest in I-joists because of their advantages
in preventing cold bridging; and the capacity to easily form thicker
walls or roof panels, up to 300 - 400 mm thick, without adding
substantial weight to the structure. James Jones will be exhibiting at
Ecobuild 2010, at Stand 2102.
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