How complicated is it to put a new soil pipe access in to a public sewer?

[cinnabunbun]

Obviously I would use a professional to physically do this job.

Has anyone put in a downstairs loo quite far from their house's existing soil pipe?

I'm at the planning stage of a renovation and thinking about placement for a downstairs loo. We are in an end of terrace house with a public sewer running underground along two sides of the property.

Our current soil pipe flows into the sewer which runs along the back of the house. This will be extended over with appropriate structural support and a build over agreement from Thames Water (hopefully!)

The location I'm hoping to use for the new downstairs loo is really far from this. Approx 10 meters away. So I'm hoping to put in a second soil pipe into the public sewer where it runs under the alleyway to the side of the house closer to the planned loo. Is this possible? Is it hideously expensive? Does the water company charge a massive fee if you create a new outlet pipe?

You'd have to ask your local water supply company. At least if it's an alleyway you won't have to dig up the road, potentially apply to have a temporary traffic light, etc. Ideally you would use a firm which could handle the sewer connection including licences and paperwork, etc to fit the downstairs loo.