Best Bath Waste Position

[Ampimpaired]

Hi, I have moved the pipe-work for the bath to the other side of the bathroom.
The new bath will have the tap and waste in the centre against the wall rather than end on as with the old bath.
Is there a standard position for the waste to come through the floor.
The water pipes are now central a couple of inches from the wall and should be ok to fit using flexy pipe to allow access.
What about the waste? - Any tips for fitting where you can't see or reach easily?
Is there a recommended distance from the wall so it wont catch the main base of the actual bath tub? - and does offsett to the left or right matter?
Without having the bath to hand to check - is there a standard position?

Many thanks.

 

[Space cat]

First things first, which way do the joists run? Getting a waste pipe across joists is a pig- and best avoided if possible.

 

[Ampimpaired]

The pipe routing is not a problem it drops from the bath a few feet along side a joist into a pipe dropping below/across the joists to the main stack.

It is just how close to the wall do I need to go, at the moment I have set it at 18cm (or about 17 cm once the tiles are on the wall) and ofsett lengthways from the centre of where the bath centre will be by about 20cm.

I can move it closer to the wall by changing the length of the pipe - I just need to decide the final position before I lay the new flooring!

The other issue is connecting the bath waste on the wall side where it will be difficult to reach/see. - any tips for that would be great!

Thanks.