"Tony Bryer" wrote in message
...
In article ,
Mary Fisher wrote:
What were the reasons for it not catching on? Just too new,
people too suspicious of something unfamiliar? Presumably it
had been tested and proved to be suitable.

At a guess (a) cost: though the builders probably weren't
factoring in the time saved in drilling holes for servicing,
sorting out twisted joists etc; (b) need to be ordered to length
probably several weeks ahead, whilst for 8x2 you can phone a
timber yard and they'll be delivered tomorrow; (c) they probably
needed somewhat more careful handling which cannot be relied on
on many UK sites; (d) they might (though might not) be damaged
by overloading - as might occur when the bricklayers have loads
of bricks or blocks stacked on boards across the joists.
Ordinary solid timber joists might deflect a but they'd spring
back.

So the builders need to adapt their techniques ... that happens in all
trades with all new products.

In my experience :-)

Mary

(b) and (c) apply to trussed rafters too. With these though the
time saving is more obvious. In my BCO days we did have trouble
sometimes with badly stored trusses being damaged.

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