Luxury bathroom renovation on the Côte d'Azur

Marble and limestone are mostly calcium carbonate, the same mineral as the scale on your taps. Acids dissolve it. Vinegar, lemon juice and most limescale removers leave dull, pale, rough patches on polished stone, and wiping won't bring the shine back.

The coast has hard water, so scale builds up around the taps and on the shower walls. The product sold to shift it is the one that harms the stone. Ask the stone supplier which cleaner to use against limescale, and keep anti-scale sprays away from marble. In a second home, write that down for whoever cleans while you're away.

Natural stone is porous. In a bathroom it gets a water-repellent sealer, and the sealer wears off over time. Ask the supplier how often to renew it and with which product.

Polished stone is also slippery when wet. For the floor and the shower, ask for a honed or textured finish, and wet a sample with soap on it before you choose.

A hammam (steam room) fills a closed space with hot, wet air. The steam reaches the walls and the ceiling, so the whole box has to be waterproof and vapour-tight, the floor included. A flat ceiling drips condensation onto whoever sits below. A sloped or vaulted one lets it run down the walls. Where steam gets through a joint, it soaks the plaster or timber behind, out of sight. Ask how the walls and ceiling are sealed against steam.

The steam generator needs its own protected electrical circuit and an isolating switch. It sits outside the steam room, somewhere dry, ventilated and frost-free. A larger generator may need a bigger electricity subscription, so ask before you choose the model. Hard water scales up a generator the way it scales a kettle. Ask what descaling it has and who will service it.

The room also needs an air inlet and a way to dry out fully after each session. Settle how that works before the tiler starts.

On tax, a ready-to-fit cabin is supplied at 20% TVA (French VAT), with only the fitting at 10%. A steam room built to measure, where the room is altered, plumbed and tiled, takes 10% on supply and fitting. On insurance, the generator counts as equipment, so it carries no ten-year cover.

The law doesn't require any of them. An architect is compulsory only for some planning applications, and a bathroom renovated inside the house needs no permit. Who designs it is your call.

"Architecte" is a protected title in France. Only people on the register of the Ordre des architectes (the architects' professional body) may use it, and the register is public. "Architecte d'intérieur" (interior designer) isn't regulated, so anyone can print it on a business card. Ask about training, insurance and finished bathrooms you can see. The title alone guarantees nothing.

A designer who also runs the work acts as maître d'oeuvre (project manager) and takes on a builder's liabilities. Ask for their professional liability and décennale (ten-year building insurance) certificates. The contract should say whether they run the site visits and the réception des travaux (formal handover), or only produce the drawings. If you live abroad for part of the year, that line matters most.

Leaks come first. The waterproofing is a hidden membrane under the tiles, because tiles and grout never keep water out on their own. If it fails under a shower and the room, or the rooms around it, become unusable, the décennale can apply. The insurer decides case by case after an expert visits. Get the insurer's name and policy number on the devis, and ask whether the insurer treats that waterproofing system as standard work.

Faults in the finish are treated differently. Crazing, hairline cracks that don't leak, stains and surface mould generally fall outside the décennale. The AQC, the construction-quality body funded by insurers and the State, notes the bar can shift for a luxury hotel. Don't count on that in a private house. For those faults you rely on the contractor's ordinary liability, and you have to show a fault. Normal wear isn't one.

Taps, mixers, towel rails and a steam generator added to an existing home have had no ten-year or two-year cover since a 2024 court ruling. The fitter's contract and the maker's warranty are what's left, so keep the warranty papers.

On an expensive finish, walk the room in daylight before you sign the handover report, and list every chip and scratch on it. The FAQ below explains what happens to a flaw found later.