G13/AS1 table 7 gives minimum spacing of support for pipework. When a graded discharge stack is to be supported by timber planks slung under a suspended timber floor, the support spacing is obviously not the same thing as the spacing of the straps bearing the supporting planks.  Is there any acceptable or typical standard for such support planking? For example 150x25 H4 with 25x1 straps at say 1.8 centres? 



Linkback: https://www.plumbers.nz/drainage/83/support-for-your-graded-discharge-stack/1084/