Table of Contents
A bathroom in a Turku flat costs what it costs. A standard 4–6 m² wet room, stripped to the concrete and rebuilt properly, lands somewhere around 8 000–15 000 €, and takes two to three weeks unless something has to dry first. Detached houses on Hirvensalo or Kakskerta run wider, 8 000–20 000 €. Those are the honest numbers. The jobs that end up at 21 000 € or 25 000 € are rarely the ones that started with a bigger plan — they are the ones that started with a cheaper plan and then went wrong. After enough of these projects you stop seeing bad luck and start seeing the same seven decisions.
1. Choosing on price alone, and comparing quotes that are not the same job
Three quotes at 6 500 €, 9 200 € and 13 800 € do not describe three levels of greed. They usually describe three different scopes. One includes demolition, waste removal to the tip, electrical work, a new floor drain collar and the membrane certificate; another quietly leaves out waste, assumes the existing electrics pass, and prices tiling from the customer’s own materials. The only way to tell which is which is to read each firm’s published scope rather than its total. Those documents are indexed in Finnish under Kylpyhuoneremontti Turku, and putting two of them side by side is how you find the quote that is missing 4 000 € of work. Do that before you compare the totals, not after the invoice arrives.
2. Skipping the muutostyöilmoitus and hearing about it from the board
In a taloyhtiö — the housing company that owns the building — a shareholder must file a muutostyöilmoitus, the alteration notice, with the isännöitsijä (the property manager) or the board before work starts. Wet-room work always requires it. The board may appoint a supervisor, normally at your expense, and that is a few hundred euros you can plan for. What you cannot plan for is the alternative: demolition already done, the board objecting, work halted while the notice is processed. A stopped site in a 1970s block in Varissuo or Runosmäki means a bathroom out of use for weeks longer, a contractor whose crew has moved to another job, and in the worst case a demand to open up finished work so it can be inspected. The notice takes an afternoon. Ignoring it has cost people the price of the renovation twice.
3. Economising on vedeneristys, or letting the wrong person do it
The vedeneristys — the waterproofing membrane — is the layer that decides whether the room lasts twenty-five years or leaks in six. It is also invisible once the tiles are on, which is exactly why it attracts savings. It must be installed by someone holding the Finnish personal certification for wet-room waterproofing, and it must be photographed and documented before tiling. Shaving 600 € off that line item to save money is the worst trade in the building trade: a leak found later means demolition, drying, replacement of the neighbour’s ceiling below, and a repeat of the whole renovation at full price. Bathrooms built before roughly 1999 often have no certified membrane at all, just tile on a screed — which is why so much of Turku’s older stock needs the full job rather than a refresh.
4. Getting the floor falls wrong
Water has to reach the lattiakaivo, the floor drain, on its own. If the gradient is flat, or falls the wrong way, or dips into a shallow pool by the shower wall, the room does not fail immediately — it fails slowly. Standing water sits on the seams, the silicone goes first, the grout follows, and five or eight years later you have staining at the skirting and a moisture reading nobody wants to see. This is one of the few faults a homeowner can check before the tiles go down: pour a bucket of water on the finished screed and watch where it goes. If it does not run to the drain, it never will.
5. Ignoring ventilation, so the new room grows the same mould as the old one
People replace a mouldy bathroom and keep the extraction that made it mouldy. A new membrane does nothing about air that never moves. In older blocks the shared extraction has often been throttled by decades of adjustments elsewhere in the building, and a 1930s stone house in Martti or Portsa may be running on natural ventilation that stopped working when the windows were replaced. Measure the extraction rate before you spec the room, check whether the replacement air actually has a route in, and factor in that changing mechanical ventilation can require a permit from the local rakennusvalvonta (building control). Otherwise you have paid 12 000 € for the same problem in nicer tiles. The Finnish-language rundown published as kylpyhuoneremontin 7 virhettä makes the same point, and it recurs because ventilation is the part nobody photographs.
6. Choosing fittings and tile layout after demolition has started
Every undecided detail becomes a stopped site. The tiler cannot set out a wall until the shower mixer position is fixed; the electrician cannot finish until the mirror cabinet is chosen; a tile ordered mid-project arrives in nine days rather than being on the pallet in week one. Each of those is a day or two of idle time, and idle days on a fixed-price job get renegotiated as extras. Decide the fittings, the tile, the layout and the drain position before the first wall comes down, and put them in the contract as a list. Late changes are not free just because the room is already open.
7. Accepting no documentation
If there are no photographs of the membrane, no waterproofing certificate, no written fixed-price contract and no warranty terms on paper, then you own the risk and you cannot prove anything. That matters when you sell — a buyer’s surveyor asks for exactly these documents — and it matters more if something fails. The Finnish Competition and Consumer Authority sets out how consumer contract terms and disputes are handled at kkv.fi, and every route it describes begins with what you agreed in writing. A verbal promise from a good tradesman is worth something. It is not worth 12 000 €.
The habit that prevents most of them
Write things down before they happen, not after. The scope, the notice to the taloyhtiö, the certificate holder’s name, the fittings list, the warranty terms, the photographs at each stage. Six of these seven mistakes are decisions deferred until the room is already open and deferring costs money. The seventh is the absence of the paperwork that would have caught the other six.
