A bathroom renovation budget that covers more than the tiles

Investigate the stains and slow drainage first

Tell the contractor about smells, recurring mould, loose finishes, leaks and water that takes too long to drain. Include when each problem occurs and whether adjoining rooms or the flat below have been affected. Those observations are useful starting points; a new surface should not be used to conceal an unresolved cause.

The inspection needs to establish what can reasonably be retained and what requires further investigation after removal. Ask how unexpected damage will be recorded, priced and approved. Include ventilation and electrical work in the assessment. Ask the relevant professionals which requirements apply to the planned work in your Spanish property and which parts of the existing installation can be kept.

Official source: CTE · Documento Básico HS Salubridad · BOE · Reglamento electrotécnico para baja tensión (REBT)

Try the room with its doors open

Measure the room, recesses, window, door swing and current connections. Place the proposed basin, toilet and shower at their actual product dimensions. Allow space to open drawers, step into the shower and stand comfortably at the basin. A cabinet that fits against the wall can still block the route through the room.

Compare retaining the layout with moving a specific fitting. Ask what that move means for drainage routes, floor levels, water connections and the surfaces that must be opened. The useful comparison holds the fittings and finishes constant so that the cost of the layout decision remains visible. Include the needs of the people who will use the room, now and over the coming years.

Separate the spending limit from the contractor's price

Suppose an owner has a hypothetical €8,000 available and chooses to keep €1,000 as a reserve. That leaves €7,000 for the agreed works, products and applicable tax. These figures are an illustration of budgeting, not a market quotation or a claim that €7,000 will buy a complete bathroom renovation.

Use that remaining amount to test a written specification. Include strip-out, waste, preparation, services, waterproofing, fittings, tiling, decoration and the agreed checks at completion. A tile supply price says nothing about the cost of removing old finishes or producing a suitable surface underneath.

Keep waterproofing in the specification

Waterproofing needs to be designed around the selected shower and finish system. Ask the appropriate professional to specify the prepared substrate, compatible products and treatment of corners, penetrations, joints and drain connections. Follow that system's current instructions, including the checks required before it is covered. New tiles and a neat visible seal do not establish what has been installed beneath them.

There are easier places to simplify. Compare standard product sizes, a smaller selection of finishes or less elaborate furniture, while checking their suitability for the room. Look at cleaning access and replacement parts as well as appearance. Savings that depend on skipping necessary preparation should prompt a closer conversation about the proposed method.

Official source: Schlüter-Systems · KERDI, ficha técnica 8.1

Agree the awkward details before work starts

A small bathroom still involves several trades and a sequence of work. The written agreement should make clear who coordinates them and who checks that one stage is ready for the next. If it is your only bathroom, discuss the periods when it will be unusable before choosing a start date.

• Confirm which fittings, accessories and finishes are included by model or agreed specification.
• Record preparation, waterproofing, drainage and electrical work separately enough to understand them.
• Ask who handles waste, protects the route through the flat and makes good adjoining surfaces.
• Agree how hidden damage and any owner-requested changes will affect cost and completion.
• Confirm when the selected products will be delivered and when the finished bathroom may be used.

Inspect the finished room as someone who uses it

Arrange a handover that includes the agreed professional checks, operation of fittings and a record of anything still to be corrected. Open the cabinet doors, inspect accessible joints and ask to see how the screen and drain are cleaned. Request product care information and relevant installation records rather than relying on a verbal assurance that everything is fine.

Work may look complete before an adhesive, sealant or other product is ready for use. Ask the installer to confirm the applicable waiting and care instructions. Write down outstanding items and the arrangements for resolving them so they do not disappear into a series of informal messages.