Bossing shower waste into soil pipe vs. separate shower waste

[CitizenErased]

Hi,

We're in the process of upgrading 2 bathrooms in our house: the ensuite and the family bathroom. These adjoin one another. The ensuite is largely done so has all piping in situ. The ensuite required that we feed its soil pipe through the wall into the family bathroom, where it angles outside and runs across the outside of the house into the soil stack. The soil pipe should be visible in the below photograph of the family bathroom. The ensuite toilet is against (with 120mm boxing) the wall that the soil pipe comes through/ is on the other side of the wall.

The shower/bath in the family bathroom is due to have its head (shower) above the soil pipe that can be seen in the below photograph. The bath is 1700 (the length of the room) x 750 and its waste is in its centre. It has an overflow inlet. The clearance beneath the bath should be ~140mm.

The soil pipe that can be seen below exits outside at the point shown , then runs across the outside of the house to the soil stack - as per the bottom image. I believe this means that it is effectively blocking an ideal/ easy core point for a separate waste pipe to be sent outside.

We have had varying advice on how to deal with the waste for the family bath:

1. Boss the bath's waste pipe into the soil pipe internally (the one in the below image);
2. Core a separate hole and send the waste outside separately, to join the soil stack.

I believe 2) may need to go under the floorboards and then out. Someone said that this meant there would be a large drop from the bathtub (that will sit on feet to clear the soil pipe shown below) and that bossing was the best option in all the circumstances; they added that ideally there would be a separate waste but in the circumstances with the existing pipes etc, bossing would be best. I'm not sure if there is another option; I'm hoping to chat through the options a bit more early next week when our fitter is able to chat through in person.

I'd be most grateful for any suggestions or assistance. If any more details would help, please just let me know.

Many thanks

 

[ShaunCorbs]

You normally want to boss in from the top on horizontal soil pipework else you could get a blockage / problems very rare

 

[CitizenErased]

You normally want to boss in from the top on horizontal soil pipework else you could get a blockage / problems very rare

Thank you, Shaun. If bossed I think it would be at a 10 o'clock position. I think the intended entry point can be seen in the top photo, where there is a "cleaner" circle to the right of what looks like a "2".

 

[ShaunCorbs]

Thank you, Shaun. If bossed I think it would be at a 10 o'clock position. I think the intended entry point can be seen in the top photo, where there is a "cleaner" circle to the right of what looks like a "2".

10 o’clock / 45 degrees would be better than horizontal and acceptable