When bathroom work in a flat needs your neighbours' sign-off

Why a bathroom is not like any other room

Most rooms in a flat are self-contained: what you do to your bedroom floor stays your business. A bathroom is different because the risers running through it usually serve several flats stacked above and below you, and the waterproofing under your tiles is the only thing standing between your shower and your downstairs neighbour's ceiling.

That is why bathroom renovations sit closer to shared building matters than ordinary redecorating, even though the walls of the room are entirely inside your own flat. The building register and the association's rules exist partly to keep track of who has touched what, in case a leak or a blockage needs tracing later.

What usually needs the association's consent or notice

Anything that touches the shared risers is the clearest case. If you plan to move, replace, or reroute the vertical stack that also serves flats above or below, the housing association normally needs to know, and often other owners on the same riser need a say too, since shutting off water for the work affects them directly.

Waterproofing is the other big one. If you are changing the floor buildup in a way that affects the slab shared with the flat below — a different height, a different membrane, or removing an old layer entirely — this is worth flagging to the association even if no permit is formally required, because it is the kind of thing people want to know about before, not after.

• Moving or replacing a shared plumbing riser or stack
• Rerouting pipework that passes through the floor slab to the flat below
• Changing the floor waterproofing system in a way that alters the slab buildup
• Any work that requires shutting off water to the whole riser, even briefly
• Structural openings in the slab or a load-bearing wall — always a specialist matter, not one for a bathroom guide

What is simply your own decision

Replacing a toilet, basin, shower tray, or bath with an equivalent unit on the same connections is your own decision, as is retiling, repainting, changing a vanity unit, or fitting a new extractor fan that uses the existing duct. None of this touches shared systems, so there is nothing to report.

The same goes for changing taps, showerheads, or a heated towel rail on the existing radiator loop, and for any work that starts and ends inside your own walls and floor without altering what is shared. If you are unsure whether something counts as shared, the safest test is whether it could affect the flat below if it went wrong.

Noise and working hours — what neighbours expect

Demolition — breaking out old tiles, chiselling a shower tray free, taking a floor back to the slab — is the loudest part of any bathroom job, and it is worth telling your immediate neighbours the day before, even where no formal notice is required. Most buildings have an unwritten expectation of no drilling or hammering early morning, late evening, or on Sundays.

Many associations set their own quiet hours in the house rules, which can be stricter than general good sense would suggest, so it is worth checking before booking a contractor for a specific day. A short message on the stair noticeboard costs nothing and avoids most complaints before they start.

Where to get a precise answer for your building

House rules vary: some associations ask for written notice on any wet-room work, others only care about the riser. Your management company or board can tell you what your specific building requires, and the building register is worth checking if you suspect a wall you plan to move might be load-bearing or otherwise recorded.

We do not give permits ourselves and we do not touch load-bearing walls or gas installations, but we can tell you plainly, from the plans or photos, whether a job you are planning is likely to need the association's input or not, before you commit to a date.

How a larger bathroom renovation usually runs

A full bathroom renovation typically starts with a site visit or photos, a fixed quote, and a check on anything riser- or waterproofing-related that might need clearing with the association first. From there it runs through demolition, plumbing, waterproofing, tiling, and fittings, usually over one to two weeks depending on scope.

Our bathroom renovation work starts from 3 500 € per job with a fixed quote agreed beforehand, and plumbing on its own is charged from 45 € an hour if it is a smaller job rather than a full renovation. General flat renovation work outside the bathroom runs from 180 € per job on the same fixed-quote basis.