A bathroom designer creates a functional and attractive bathroom, shower room or wet room plan tailored to a client's space, accessibility needs and budget. They produce technical drawings for sanitaryware placement, tiling, waterproofing and services (plumbing, electrics and ventilation), and may also manage the installation. Bathroom design is not a regulated profession in the UK but the KBSA (Kitchen Bathroom Bedroom Specialists Association) is the leading industry trade body whose members must meet defined standards of professionalism and trading. Showroom designers typically provide design services free as part of a supply contract; independent designers charge a fee.
What they do
- Survey the existing bathroom space and drain, water and electrics positions
- Produce 2D plans and 3D renders of the proposed bathroom layout
- Specify sanitaryware - bath, shower, basin, WC and storage
- Select and specify tiles, grout and feature materials
- Plan waterproofing (tanking) for wet room or shower areas
- Specify bathroom lighting within the IP zone requirements of BS 7671
- Coordinate plumbing, electrical and ventilation positions with trades
- Advise on underfloor heating and towel rail specification
- Project-manage the installation (if full-service)
When you need one
A bathroom designer adds most value when creating a wet room, making significant layout changes, or specifying high-end sanitaryware and tile combinations.
Typical costs (UK, 2025)
| Item | Typical cost |
|---|---|
| Showroom design consultation | Free (tied to purchase) |
| Independent designer - design fee | £400 - £2,000 |
| Basic bathroom renovation (supply and fit) | £3,000 - £8,000 |
| Mid-range renovation with layout changes | £8,000 - £20,000 |
| Wet room installation | £5,000 - £15,000 |
| Luxury or spa bathroom | £20,000 - £50,000+ |
Prices are for supply and fit of sanitaryware and tiling only. Structural works, re-routing drainage, electrics and ventilation are typically quoted separately. Always confirm exactly what is included in a bathroom quote.
Qualifications to look for
KBSA membership is the primary quality indicator for bathroom retailers and designers. Members must meet the association's standards of professionalism, hold appropriate insurance, and adhere to a code of conduct. Check membership at kbsa.org.uk.
A good bathroom designer or fitter should be able to specify and install appropriate tanking systems (such as BAL or Schluter Kerdi) for wet room and shower areas. Ask to see evidence of previous wet room installations and check that the tanking system proposed is appropriate for the substrate.
Bathroom electrical work must be carried out or overseen by a Part P registered electrician familiar with the special location requirements of BS 7671. Lighting, shaving points and heated towel rails all need to comply with IP zone requirements. Ensure you receive an electrical installation certificate on completion.
How to find a reputable bathroom designer
Related Calculators
Extension Cost CalculatorFrequently asked questions
What is the difference between a wet room and a shower room?
A shower room contains a shower enclosure or cubicle with a tray and a door or screen that contains water within the shower area. A wet room is a fully waterproofed room where the shower water drains directly from the floor - there is no tray or enclosure and the entire floor and walls are treated as a wet zone. Wet rooms require tanking (waterproofing) the entire floor and walls to a sufficient height, and a linear or point drain set into the floor. Wet rooms are popular for accessibility as there is no step to negotiate.
How much does a bathroom renovation cost?
A basic bathroom renovation (replacing sanitaryware in the same positions) typically costs £3,000-8,000 supply and fit. A mid-range renovation with some layout changes, tiling and new electrics costs £8,000-20,000. A high-end renovation with bespoke features, underfloor heating, and full wet room or freestanding bath costs £20,000-50,000 or more. The main cost drivers are sanitaryware quality, tile choice, the complexity of waterproofing and whether the layout is changing (which increases plumbing costs significantly).
Do I need planning permission for a bathroom renovation?
Bathroom renovations are normally permitted development and do not require planning permission. However, Building Regulations approval is required if you are adding a new bathroom to a room that did not previously have one (for example converting a bedroom), because this requires demonstrating compliance with ventilation requirements (Part F) and potentially drainage regulations. Electrical work in the bathroom must be notified to Building Control or carried out by a Part P registered electrician, even for a like-for-like renovation.