Installing ensuite - no where near existing waste pipe

With the location of the soil-pipe that manages toilet waste at the other end of the house, the answer is definitely no, this is definitely not a cost-effective option. Soil pipes are generally located on an outside wall and enter the bathroom as close as possible to the toilet location. They can be mounted on the floor, but usually pipes run below the floor in-between the floor joists. The pipe diameter is 110mm. Running this pipe from one end of the house to the other simply is not practical. It would also be necessary to run hot and cold mains water pipes into the bedroom from the nearest accessible existing pipework. This project is not practical unless a new soil-pipe was fitted externally in close proximity to the bedroom and connected to the existing soil-pipe system for starters.

Yes it is very possible. The hot and cold feeds would be very straight forward to plumb to the new en-suite. As for the toilet waste you would have some options and would have to determine which would be the best to suit (cost, mess and building time etc). You could fit a new simple stack close to toilet supply and dig up externally and join to existing waste, or you could install a saniflo system, pipe work is much smaller so could cut through joists. But I would recommend reading up on saniflo systems first as they are quite pricey.

Yer you can do this but don't take too much out of the joist. For the waste, saniflo is the answer as you can put shower toilet sink, all in them at same time and they pump up to 25 meters but they do cost a lot. Good bathroom fitter will not have a problem with this but it would cost a lot more money to do this.