New downstairs WC drainage

[RobboBCFC]

Hi guys,
hoping to get some advice on drainage layouts. I'm currently having a new WC installed downstairs.

However the existing drains are at a depth of around 1M. lower than the existing house footings. Meaning theres a big difference between new drains to existing.

I have spoken to the BCO and he has recommended an internal backdrop in the IC, however I think this isnt the best of ideas.
I have drawn a quick design and think this may be a better alternative to present to BCO, just wanted to get some feedback and whether this would be better or is there an even better alternative?

I've attached pictures. Thanks in advance

 

[Hugh Jaleak]

1m isnt deep in the grand scheme of things, I'd look at putting an external backdrop in at the chamber. Would also suggest you come away from the house further, fit a mini chamber instead of a bend, then go across to the existing chamber.

 

[RobboBCFC]

Thanks for your reply Hugh!

How would I go about putting in an external backdrop into the IC?

I can't at the sides as theres no room... The main run is being used up by the SVP.. can I just join onto that with a T and then go through the top for the rodding point? (hope that makes sense)

 

[RobboBCFC]

Hopefully this is clear

 

[Ian H]

At that depth I’d just dig it out full depth and have the rest bend deeper. I would mess about with any sort of dropshaft.

 

[rougharsedbrickie]

At that depth I’d just dig it out full depth and have the rest bend deeper. I would mess about with any sort of dropshaft.

Works for me too, 1m deep is hardly a massive dig

 

[RobboBCFC]

existing foundations arent as deep as 1meter. Thats the problem with digging all the way at 1m.

Unless theres another way to do this that Im missing?

thanks for feedback guys