A bathroom renovation is easier to control when you settle the layout and services before choosing finishes. This guide helps you build a brief for an existing bathroom, ask useful questions of installers and spot omissions in quotes. Rules cited here relate to England; check the position for your location and project.
Start with the room you have
Measure wall lengths, ceiling height, doors, windows and the position of the soil pipe, water feeds, extractor and radiator. Photograph each wall and note where the floor or walls show signs of movement or damp. The measurements are a starting point for discussion, not a substitute for an on-site survey.
- Who uses the bathroom, and when is demand highest?
- Would better storage solve more than a larger fixture?
- Can the door, window and existing drainage positions remain?
- Where can towels dry, and how will the room be ventilated?
Choose the layout before the look
Draw at least two simple layouts. In each one, check that doors and drawers can open, there is space to use the basin and toilet comfortably, and access is possible for future maintenance. Moving a WC or shower can affect drainage and floor construction; discuss feasibility before buying fittings. Keep product dimensions and installation instructions with the plan.
Plan water, electrics and ventilation together
A bathroom needs careful coordination between trades. Ask how the installer will protect the structure from water, what surfaces will be prepared before tiling, how plumbing will be accessed if repairs are needed and how extraction will work. Agree the locations of lights, switches, shaver points and heated towel rails before the walls are closed.
A like-for-like refit with new fittings does not generally require building regulations approval in England, but drainage or electrical work may do, and adding a bathroom in a new location is more likely to need approval. The Planning Portal kitchen and bathroom guidance explains the distinction. Ask the relevant professional or building control body about your exact scope; never assume that a simple looking change is exempt.
Write a specification that can be priced
A quote is only useful when it describes the same project you expect to receive. Record the make and model of the main fittings if chosen, or set clear allowances. Specify how much wall and floor area will be tiled, the tile size, any niches or boxing, whether the ceiling is included, and who supplies grout, trims and sealant.
- Removal and disposal of the old bathroom.
- Plumbing and electrical work, including testing and certificates where required.
- Substrate repair, waterproofing and surface preparation.
- Ventilation and heating changes.
- Fittings, tiles, flooring, paint and finishing materials.
- Making good outside the bathroom and final cleaning.
Compare quotes line by line
Ask each installer to identify exclusions, provisional sums and assumptions about the condition of the room. Check whether VAT, waste removal and delivery are included. Do not compare one fully specified quote with another that leaves the shower, tiles or preparation as open allowances. Ask who is responsible if a chosen product is delayed or arrives damaged.
For a broader approach to budgets and written scopes, read our home renovation planning checklist.
Agree the order of work and handover
A typical sequence is survey and specification, ordering, strip-out, hidden repairs, first-fix services, wall and floor preparation, waterproofing where needed, finishes, fitting and testing. The actual sequence depends on the construction and products used. Leave time for drying and curing as instructed by manufacturers; a rushed handover can undermine good materials.
At completion, test taps, drains, lights, heating and extraction. Check the sealant and visible finishes, ask for care instructions and keep receipts, warranties and any certificates with your project record.
Bathroom brief: the essential questions
What stays in place? What moves? Who supplies each product? Which surfaces are included? What happens if the substrate is damaged? How will ventilation, waterproofing and maintenance access be handled? Which certificates will you receive? When are decisions and deliveries needed? If a quote does not answer these questions, ask before accepting it.
Sources: Planning Portal: kitchens and bathrooms and GOV.UK: Approved Document F. Requirements depend on the work and may change; confirm them with the relevant authority or qualified professional.