"Andy Hall" wrote in message
...
On Wed, 10 Nov 2004 01:11:52 -0000, "IMM" wrote:


"Andy Hall" wrote in message
.. .


If the fittings are placed tightly to the joists then there may be
insufficient provision for expansion and contraction and therefore a
potential straining of the joints. Undulation in the pipe may provide
enough expansion capability but care does need to be taken to ensure
that there is provision for thermal effects.

Plastic joints should be well clipped either side to avoid strain on the
joint.


In fact they should be clipped in a way to allow longitudinal movement
for thermal expansion. For 22mm tube, support is only required for
horizontal runs every 0.5m anyway and the OP has a space of 300mm.

They should be clipped either side of the joint which will not restrict
thermal expansion.