What does a new bathroom cost, and how long does it take?

We do the plumbing side of bathrooms, so this is written from that end: what makes the plumbing bigger or smaller, and what order the whole job has to run in. Tiling, plastering and electrics are separate trades.

What makes it cost more

1. 1

   Moving the toilet

   The waste has to fall the right way to reach the soil pipe. Move the toilet and you are often into floor work or boxing in. Keeping it where it is is the biggest single saving available.

2. 2

   Changing the layout

   Swapping a bath for a big shower enclosure, or moving the basin across the room, means new hot, cold and waste runs in walls and floors.

3. 3

   What you pick

   The suite, the shower and the taps can vary by a lot for the same installed job. This is the part you control most.

4. 4

   What is behind the old one

   Nobody knows until the rip out. Old lead or steel pipework, rotten floorboards and previous bodged work are the usual surprises, and any honest quote allows for the possibility rather than pretending it cannot happen.

The order it has to happen in

This is what people wish they had known, because it explains why a bathroom takes a fortnight when the plumbing is a few days.

• Rip out, then first fix plumbing and any electrics in the walls
• Plastering or boarding
• Tiling
• Second fix plumbing: suite, taps, shower, towel rail, all connected and tested
• Silicone, final checks and the bits everyone forgets

Skip an order and something has to come back out. The waiting between stages, and waiting on parts that were ordered late, is where bathrooms actually lose time.

How to keep it under control

• Get the plumbing looked at before you order the suite
• Keep the toilet where it is if the budget is tight
• Have everything on site before the rip out starts
• Agree who is doing tiling and electrics before day one, not during