A bathroom installation replaces your old suite with new sanitaryware, a bath or shower, tiling and fittings, including the plumbing, electrics, ventilation and waterproofing needed for a complete, watertight room.
For a homeowner in Carshalton, planning a new bathroom tends to begin with two questions: what will it cost, and how disruptive will it be? Our guide range is £6,500–£15,500 including VAT, and a typical job runs to 1–2 weeks per bathroom. Both numbers firm up once we have seen the property, measured up and agreed exactly what is included.
- Guide price
- £6,500–£15,500 inc VAT
- Time on site
- 1–2 weeks per bathroom
- Postcodes
- SM1, SM2, SM3, SM4 and SM5
- Planning rules
- England
- Local area
- Greater London
- Survey
- Free, with a written quote
What should you budget for a new bathroom in Carshalton?
Here is how the guide price for a new bathroom breaks down in Carshalton. We start from national figures and adjust for London, which comes out about 30% above the national guide. The resulting range, VAT included, is £6,500–£15,500, and a survey, at no cost to you, firms it up.
| Type of job | What it usually involves | Guide in Carshalton |
|---|---|---|
| Shower room or en-suite | A compact room with a shower, basin and toilet, keeping the existing layout. | £5,200–£10,500 |
| Family bathroom | A full suite with bath and shower, new tiling, lighting and an extractor fan. | £6,500–£15,500 |
| Premium bathroom or wet room | Standalone bath, wet room or walk-in shower, underfloor heating and large-format tiles. | £15,500–£26,000 |
The main things that change the figure:
- Room size and the amount of tiling
- Suite, shower and tap specification
- Wet room waterproofing and underfloor heating
- Condition of the floor, walls and existing pipework
What do you get?
- Measured survey and layout planning for your room
- Removal and disposal of the old suite and tiles
- Electrics, lighting and extractor fan by qualified trades, with certificates
- Waterproofing behind showers and in wet areas
- Wall and floor tiling to your chosen design
- Bath or shower, basin, toilet and taps fitted and tested
Local housing and a new bathroom
London's housing is dominated by Victorian and Edwardian terraces, often in yellow London stock brick, with Georgian terraces in central districts and mansion blocks across many inner areas. Outer boroughs have large belts of interwar semis, and there are extensive post-war council estates. Many houses have been split into flats, and conservation areas are widespread.
London Clay shrinks and swells with the seasons, and street trees close to houses can contribute to movement, which affects foundation design.
None of this holds for every street in Carshalton, which is why we look at your actual house before pricing a new bathroom rather than assuming from its age alone.
Permissions for a new bathroom in Carshalton
Which rules apply depends on where you live. For Carshalton, the answer is England, and the points below reflect that; we verify them with the council before quoting.
Internal work such as a new kitchen, bathroom, flooring, plastering or decorating does not need planning permission in England, unless the house is listed, when listed building consent may be needed even for internal changes.
Some internal work is covered by Building Regulations: new electrical circuits and work in bathrooms (Part P), new drainage, structural changes, extractor ventilation and any new window. Notifiable work is certified by a registered installer or by building control.
Rules change and every property is different, so we check the planning history and constraints for your address before we quote.
How does the job run?
A visit to your home
We arrange a free site survey on a date convenient to you. We measure up, look at the existing structure and access, and discuss your plans for a new bathroom so the price reflects your home.
Price and scope agreed
The quote arrives in writing, not over the phone. It covers the full scope, the finishes you've chosen, any exclusions and the payment schedule, with a fixed price tied to that specification.
Dates and permissions
Next comes planning the work itself. We set a start date that suits you, line up the right trades, and make sure any approvals for a new bathroom are in place before the first day on site.
On site to finish
During the work we protect the areas around it and tidy up at the end of each day. Once complete, we check the finish, remove our materials and hand over paperwork such as building control sign-off where it applies.
How we work
Frequently asked questions
Is a wet room right for my home?
A wet room is a fully waterproofed room with a shower area that drains through the floor, with no tray or step. It suits accessible bathrooms and modern designs, and makes cleaning easy. It needs a floor with enough depth for a gentle fall to the drain, and careful tanking of the whole room. Timber floors often need strengthening. We check suitability at the survey.
What ventilation does a bathroom need?
A bathroom needs mechanical ventilation, usually an extractor fan, to remove steam and help prevent condensation and mould. Building regulations set minimum extraction rates for new or refitted bathrooms. A fan linked to the light with an overrun timer, or one with a humidity sensor, works well. Ducting should vent outside by the shortest practical route. We include a suitable fan in every bathroom quote.
Do I need a new boiler for a new shower?
You do not always need a new boiler for a new shower, but your hot water system decides what kind of shower will work well. Combi boilers suit mixer showers directly from the mains. Tank-fed systems may need a pump for good pressure, and electric showers heat their own water. We check your boiler, cylinder and water pressure during the survey and recommend a shower to match.
What happens at the survey?
We visit your home at a time that suits you, look at the area involved, take measurements and check access, condition and any services that might be affected. We talk through what you want from a new bathroom, explain the options and answer questions. There is no charge and no obligation; afterwards we send a written quote.
Is the price fixed?
Yes, for the specification we agree. Your written quote sets out exactly what is included at a fixed price. It only changes if you ask for something different, or if a problem the survey could not reasonably reveal later needs extra work. In either case we explain the change and confirm it in writing before going ahead.
Near Carshalton
We cover every part of Carshalton, including SM1, SM2, SM3 and SM4, and nearby Wallington, Sutton and Mitcham. Wherever you are within that patch, the survey is free and the quote comes to you in writing.