What makes one bathroom cost more than another

Why is floor area a poor guide to bathroom cost?

Owners often ask for a price per square metre. In a bathroom it makes little sense, because most of the work is not proportional to the floor. A small en-suite still needs strip-out, a plumber, an electrician, waterproofing, a tiler and fitting; it simply has less tile. The fixed parts of the job are similar whatever the size, and the variables are the decisions below.

Which hidden factors add the most?

• The state of the pipework. If supply or waste pipes are old, corroded or badly laid, they must be replaced, and in a full renovation we replace them anyway.
• Moving things. Relocating the WC means a new connection to the soil stack; relocating the shower means a new waste route with enough fall. Both may involve opening more floor.
• The walls. Walls that come away when the old tiles are removed, or are far from flat, need rendering or boarding before tiling.
• The floor build-up. If a flush shower requires raising the bathroom floor or cutting into the screed, that adds work.

None of these are visible in a photo of a tired bathroom, which is why the final quote follows a visit.

How do your choices change the quote?

Shower type. A floor-level walk-in shower formed in the screed involves more work than placing a tray. Finish. Large-format tiles need flatter walls and more careful handling; a seamless finish involves multiple coats and preparation. Fittings. Concealed mixers, wall-hung WCs and integrated counters need framing and more planning than exposed or floor-standing alternatives. Niches, benches and lighting. Each adds a line to the quote.

None of these is a bad choice; they are simply where the budget goes. See walk-in showers and seamless bathrooms for what each involves.

Does the location of the property matter?

Access matters more than the town. A fourth-floor apartment without a lift, a villa at the end of a narrow track, a building where the community restricts working hours or lift use, or a property where debris must be carried a long way to a skip all add time. So does a property that is occupied during the works, because the area must be sealed and cleaned daily.

What is usually included, and what is not?

Our quotes list each task separately: strip-out and disposal, plumbing, electrics by authorised partner installers, waterproofing, finishes, fitting and a final clean. Materials appear either included or as labour only, depending on whether we source them. Things often outside a bathroom quote are furniture not built in, decoration of adjoining rooms and any paperwork with the town hall.

For a detailed look at how renovation costs are built up and what moves them up or down, our sister site presupuestoreforma.eu covers it from the budget side.

Why do two quotes for the same bathroom differ so much?

Usually because they are not describing the same job. One contractor includes renewing all the pipes, a full waterproofing stage and levelling the walls; another assumes the existing pipes are fine, waterproofs only the shower tray edge and tiles over what is there. On paper both say “bathroom renovation”. Only an itemised quote, with each task, unit and quantity listed, lets you see which is which.

A very low quote is not necessarily dishonest, but it often means something has been left out or will appear later as an extra. Ask what happens if the pipes turn out to be in poor condition, and whether that is included or charged separately.

How do you get a reliable figure?

Send photos of each wall, the floor, the ceiling and the shower or bath, the approximate floor area and a note of what you want to change. We give a first assessment, then visit and prepare an itemised quote. If you are comparing quotes, compare them line by line rather than by the total; the bathroom contractor checklist helps with that. For the full scope of the work, see bathroom renovation.