Waste pipe query

[leemkule]

This is probably a silly question, but please bare with me.

 

If a 32mm basin waste maximum run is 1.7 meters, does that mean the entire pipe run from basin to larger waste pipe can be a maximum of 1.7 meters, or does it just mean a single part of the run can't exceed 1.7 meters, I'm sure it's the former but I'm just wanting to double check.

 

If that's the case, can I use a coupler to go from 32mm > 50mm (50mm rather than 40 as I have spare pipe already) to allow a longer total length, obviously provided the fall is okay.

 

Thanks for any advice.

[Russell griffiths]

32mm under the sink, change to a larger pipe as quickly as you can, literally 50mm from the trap. 
 

[JackofAll]

7 hours ago, Russell griffiths said:

32mm under the sink, change to a larger pipe as quickly as you can, literally 50mm from the trap. 
 

Am curious, why is that?

[Russell griffiths]

13 minutes ago, JackofAll said:

Am curious, why is that?

Because 32 is absolutely rubbish, it does not allow for a flow of water and bubbles or air, a larger bore pipe allows water to sit at the bottom and air to pass over the top. 
32 really needs doing away with.