What's typically involved in a bathroom installation, and why does the drainage run matter so much?
Scope ranges from a like-for-like suite swap through to full refits with new pipework, but the distance to the existing waste pipework and soil stack usually drives cost and complexity more than the fittings themselves.
A straightforward swap - replacing an existing toilet, basin or bath with a similar one in the same position - is usually the quickest job, since the existing pipework and drainage stay largely unchanged. Repositioning fittings, adding a second bathroom, or converting a bath to a shower typically needs new pipework runs, and this is where the drainage run becomes the main factor: a toilet or shower close to the existing soil stack is generally more straightforward to connect than one moved to the opposite side of a room, since a longer run needs the right fall and routing to work properly. This is one of the first things worth checking at survey stage, before decisions are made on layout.