Waste Discharge Design

[ricardo100671]

My plumber has designed our bathroom sewage as per the picture below. All branches are 50mm pipework and there is a rodding access on the stack branch. Our Inspector said that all braches need to be 110mm up to each service point and can then be reduced down. Claiming this is because they are below floor level and for rodding purposes. But Given the connetion angles, I don't see how a 110mm pipe would be any easier to rod than a 50.

Is this design wrong please?

 

If it is an issue, would this be acceptable instead to provide better access to each branch ?

 

Thank you 

[Nickfromwales]

Your inspector is a jobsworth muppet.

 

50mm pipe can easily be rodded with a ‘drain snake’ if necessary, and they really need to take a chill pill.

 

Instal a Y branch at the kitchen sink so you can have a cleaning eye (access cap) there, and then the one most likely to cause issue is covered. 
 

Is the stack internal?

 

The general rule is not to have more than 3m of small bore water pipe, assuming 32mm for basins etc and 40mm for everything rise, or upsize if >3m which you have done with the 50mm pipe.

 

Go and push back   

[Big Jimbo]

2 minutes ago, Nickfromwales said:

Your inspector is a jobsworth muppet.

 

+1 . Are they straight out of uni ? 

[ricardo100671]

Thanks for the replies and the tip on the Y branch for a rodding eye. 

It just sounded absurd what he was saying, also claimed rodding tools are all 4" WHAT ! and he is practically retired ! I do wonder where he bought his credentials. 

 

Worse still and if I read Part H, section 2.6, correclty, it states "Appliance discharge pipes should discharge into another discharge pipe before discharging into a stack, unless they discharge to a gulley." I have all my appliances discharging to a common discharge before discharging into the stack. So to me that seems perfectly compliant right ? 

 

[Nickfromwales]

3 hours ago, ricardo100671 said:

I do wonder where he bought his credentials. 

Fell out of a Kellog's box over breakfast with the shite he's spouting....

 

3 hours ago, ricardo100671 said:

So to me that seems perfectly compliant right ? 

Yup. Most shower traps can have the throat of the trap removed for rodding / clearing with a snake. 

 

Most decent BCO's only care about the drainage from DPC and downwards, to the groundworks and sewer etc, and that you have vented or have AAV's (air admittance valves) etc. He needs a holiday, or a beer, or both. Or retire!