Max Gradient

[LA3222]

Just want to run this by the forum to get a collective opinion.

 

I have a contractor due to put a foul run in for me which will consist of an IC on my plot with approx 30m of pipe then connecting to the main sewer via a junction insert.

 

The invert of the sewer is 3m.  The contractor is going to put the IC invert at  1.5m so the foul run gradient will be 1:20 - is this going to cause blockages?

 

I'm sure I have read within this forum that the conventional thinking that 1:40 is no longer mentioned within building regs as the max, so in theory there is no max gradient.  However it's hard to get that conventional thinking out of my head and accept that it will all be ok!

 

TIA

 

Jamie

[PeterW]

It will be fine but you will need a second IC at the boundary. I would put an IC at your boundary at 1.5m and run down to the sewer connection at 30 degrees so 4.5m back from the sewer. Initial invert and IC I would put at 750mm. Much more than that and rodding may be an issue. 

 

If you start at 1.5m down, the boundary chamber will be so deep it will either need to be a full man access 1200 concrete or you’ll need to put restrict rings in a standard chamber. 

[ToughButterCup]

1 hour ago, LA3222 said:

[...]

foul run in for me which will consist of an IC on my plot with approx 30m of pipe then connecting to the main sewer via a junction insert.

[...]

 

IC ?

[AliMcLeod]

6 minutes ago, recoveringacademic said:

IC ?

 

Inspection Chamber.