So you’ve found the apartment of your dreams. Great location, nice light, decent price. You’re already mentally placing your sofa. And then, during the visit, you notice a small brownish stain on the bathroom ceiling. “Oh, that’s nothing,” the seller says with a smile. “Just an old leak, it’s been fixed.”
Sure. But has it really ?
Plumbing is honestly one of the most underestimated issues when buying an apartment. People obsess over the kitchen layout or the floor condition, and somehow skip past the pipes. Big mistake. A hidden plumbing problem can easily cost you several thousand euros after purchase – sometimes tens of thousands if the damage has spread inside the walls or under the floor. If you’re ever facing a serious plumbing emergency in a property you’ve just acquired, sites like depannage-reparation-plomberie-urgent.fr exist precisely for those panic moments, but frankly, you’d rather not need them right after signing.
So let’s talk about what to actually check before you put pen to paper.
Start With the Obvious : Water Stains and Humidity
When you visit, don’t just look at the walls – really look at them. Run your hand along the base of the walls in the bathroom and kitchen. Is the paint bubbling ? Are there yellowish or brownish rings anywhere ? That’s moisture. Could be old, could be active. You can’t always tell just by looking, and that’s the problem.
Check under the sink. Open the cabinet. Does it smell musty ? Is the wood of the cabinet door swollen or warped ? These are signs that water has been there – regularly.
Same thing in the bathroom. Look at the joints around the bathtub or shower. If the silicone is black, cracked or pulling away from the wall, water has been getting behind the tiles. That’s a renovation job waiting to happen, not just a cosmetic fix.
Test Everything That Runs Water
This sounds obvious, but a surprising number of buyers skip it. Turn on every tap. Hot and cold. Check the water pressure – does it feel weak ? A building with old galvanised pipes often has low pressure on upper floors, and replacing those pipes in a co-ownership building is a collective decision and cost. Not always easy or fast.
Flush the toilet. Does it refill properly ? Does it keep running ? A toilet that runs continuously wastes water and money, but more importantly it signals that the internal mechanism hasn’t been maintained. Small fix in itself, but it tells you something about how the property has been looked after overall.
Run the shower for a minute. Does hot water arrive quickly ? Does the drain empty fast or does water start pooling ? A slow drain can mean a partial blockage – or it can mean a deeper issue with the drainage slope. Worth knowing.
Ask Specifically About the Pipes : Material and Age
This is where it gets a bit more technical, but stay with me.
In France, many apartments built before the 1970s still have lead pipes for the internal water supply. Lead pipes are a health risk and legally must be replaced if detected in properties used for residential rental. If you’re buying to live in or rent out, this is not optional. Ask directly : have the internal pipes been replaced ? If yes, when and with what material ?
Buildings from the 1970s and 1980s often used galvanised steel pipes, which corrode from the inside over time. The result ? Brown-tinted water, reduced pressure, and eventually leaks. Copper pipes are much better, and PER (cross-linked polyethylene) – widely used since the 1990s – is excellent for durability.
If you can access the technical room or see any exposed pipes, take a photo. A plumber can tell you a lot from just that.
The Co-Ownership Angle : Don’t Forget the Common Areas
If you’re buying in a co-ownership building (copropriété), the private pipes inside the apartment are only part of the picture. The collective pipes – risers, common drainage columns – are managed and maintained by the building’s syndic.
Ask for the last three years of co-ownership meeting minutes (procès-verbaux d’assemblée générale). These documents are legally required to be provided to any serious buyer. Look for mentions of :
– Plumbing work voted on or already carried out
– Water damage incidents reported in the building
– Upcoming works that could affect your charges
If the building voted on a major plumbing renovation last year, congratulations – that’s good news. If there’s a recurring water damage issue in the common areas and nothing has been decided yet, that’s a red flag you want to know about before buying.
Get a Professional Eye Before the Compromis de Vente
Here’s what I really think : if you have any doubt at all – any stain, any smell, any pipe you can’t identify – spend the €300 to €500 to bring in an independent building inspector before signing the compromis de vente.
Yes, the mandatory diagnostics (DDT) include some checks, but they don’t cover everything. The état de l’installation intérieure d’eau is not yet systematically required in all transactions, even though there’s been movement toward it. An independent expert is not legally required either, but it’s money extremely well spent.
Think about it this way : if the inspector finds nothing major, you sign with peace of mind. If they find a problem, you have three options – negotiate a price reduction, ask the seller to fix it before signing, or walk away. All three are better than discovering a burst pipe behind the tiles six months after moving in.
What the Law Says About Hidden Defects
French law (article 1641 of the Civil Code) does protect buyers against vices cachés – hidden defects that existed at the time of purchase, were unknown to the buyer, and make the property unfit for its intended use or significantly reduce its value. Plumbing defects can absolutely fall into this category.
But here’s the reality : proving a vice caché in court is slow, expensive, and not guaranteed. You need to demonstrate the defect existed before purchase, that you couldn’t have known, and that the seller either knew or should have known. It’s a legal battle most buyers would rather avoid.
Prevention is simply more effective than remedy here. Every check you do before signing is a potential dispute you’ll never have to have.
A Quick Checklist Before You Sign
To summarise, here’s what you want to go through on every visit or before signing :
– Visual inspection of all walls, ceilings and floors for stains, moisture, or bubbling paint
– Test all taps, shower and toilet for pressure, hot water speed and drainage
– Check under sinks and around sanitary fixtures for swelling, mould or bad smells
– Ask about pipe material and age – lead and galvanised steel are potential problems
– Request co-ownership meeting minutes for the last three years
– Bring in an independent inspector if anything looks doubtful
– Read the mandatory diagnostics carefully – and ask questions if something is unclear
Buying an apartment is one of the biggest financial decisions most people make. The plumbing might feel like a boring detail. But it’s exactly the kind of detail that can turn a great deal into a costly nightmare. Take the time. Ask the questions. It’s worth it.