Join shower waste to soil pipe (moved from Projects)

[Thisisnotapipe]

Apologies if already covered but I couldn't find a post that described my objective:

Picture hopefully describes it most clearly. I want remove my S-trap pan, put in a p-trap and add a shower on my ground floor bathroom. The main soil stack is not accessible so wanting to join the shower waste with the toilet waste.With antivac shower trap and 40cm to play with.

Is this relatively sane?
Would I need some kind of air inlet for the pan or would the antivac do the job?
Or would I end up showering in excrement?

Advice would be much appreciated

 

[Thisisnotapipe]

Anybody have any thoughts at all?

Would the drawing work? (i know i don't have best drawing skills)

 

[Hugh Jaleak]

Shouldn't be an issue, just ensure there's adequate fall on all the pipework.

 

[picasso]

Is the step into your shower 400mm high ?

 

[Thisisnotapipe]

Thank you Hugh, glad to hear. I'm a total noob!

The shower will be accessed from the room with the higher floor luckily, so will be floor level. That would be a heck of a step otherwise!
Will try to remember to put a flap for gaining access to the pipes from the side once the tray has been secured..

 

[Hugh Jaleak]

If you use a shallow access shower trap, then the dip tube in the shower waste is removable to give access to the outgoing waste pipe for cleaning. Don't forget to refit it though when finished as it form the seal to prevent foul odours coming back into the room.

 

[Thisisnotapipe]

Sounds handy thanks for the tip Hugh! Will get one of those