You opened your mailbox and found a formal notice from your society saying your flat is causing leakage into the flat below, and you have 7 days to fix it or the society will repair it and recover the cost from you.
If you live in a Mumbai housing society, this scenario plays out every single monsoon. Inter-flat leakage disputes are one of the most common and contentious issues between flat owners and managing committees. Most people do not know their rights, their obligations, or how to respond correctly. PS Group (formerly PS Civil) has handled hundreds of these disputes across Mumbai, and the first thing we tell every flat owner is this: do not panic, but also do not ignore the notice.
Who Is Actually Responsible for Inter-Flat Leakage in Mumbai?
The Maharashtra Cooperative Housing Society (CHS) Model Bye-laws are very clear on this. Bye-law No. 47 splits leakage responsibility into three categories:
- Bye-law 47(a): Repairs that the society must carry out at its own cost. This includes structural repairs, external walls, terrace waterproofing, and common plumbing lines.
- Bye-law 47(b): Repairs the society carries out but charges to the flat owner. If the leakage is caused by internal plumbing, bathroom waterproofing failure, or drainage issues inside your flat, the society can repair it and bill you.
- Bye-law 47(c): Repairs the flat owner must carry out at their own cost within a given timeframe. If your internal bathroom or kitchen waterproofing has failed and is leaking into the flat below, you get a notice under 47(c) to fix it yourself.
The key question is not “who is leaking” but “where is the source.” If the source is inside your flat (bathroom tiles, internal plumbing, kitchen drain), you are responsible. If the source is the external wall, a common terrace, or a structural crack, the society is responsible.
This is exactly where most disputes begin. The society assumes it is your fault and sends a 47(c) notice. You believe the problem is external and refuse to pay. Both sides are guessing.
What a Proper Inter-Flat Leakage Notice Should Look Like
Under the Maharashtra CHS Model Bye-laws, a valid leakage notice must include:
- The specific bye-law under which it is issued (usually 47(b) or 47(c))
- A clear description of the leakage problem and which flat is affected
- The repairs required and who is expected to carry them out
- A reasonable timeframe to respond or begin repairs (typically 7 to 15 days)
- The consequence of not acting (society will repair and recover costs, or escalate to the Registrar)
If your society sends a vague WhatsApp message saying “fix your leakage or we will charge you,” that is not a legal notice. You have the right to ask for a proper written notice citing the specific bye-law.
What to Do When You Receive the Notice
Do not ignore it. Under bye-law 47, if you fail to act within the timeframe given, the society can enter your flat, carry out the repairs, and recover the full cost from you, plus a 10% surcharge in some cases. Worse, if the leakage causes structural damage or health hazards, the society can escalate to the Registrar of Cooperative Societies under Section 78 of the Maharashtra Cooperative Societies Act, 1960.
Here is what you should do:
- Respond in writing within the timeframe. Do not WhatsApp the secretary. Send a formal letter or email to the society acknowledging the notice.
- Ask for a joint inspection. Both flats (yours and the one below) should be inspected together with a committee member present. This prevents one-sided accusations.
- Demand source identification. Before anyone starts breaking tiles, get a proper moisture mapping or thermal imaging scan done. PS Group’s PS Leak Detect service uses non-invasive thermal imaging to trace the exact source of seepage without demolition. If the source turns out to be external, the notice should go back to the society under 47(a).
- Get a written report. A thermal imaging report gives you documented evidence of where the water is actually coming from. This protects you whether the source is your bathroom or an external wall crack.
What If the Society Is Wrong About the Source?
This happens more often than you think. In older Mumbai buildings (especially those 15-20+ years old in areas like Andheri, Borivali, and Goregaon), seepage often travels along structural beams or through cracked external plaster before showing up as a damp patch on a ceiling. The flat owner below sees a wet ceiling and assumes it is the bathroom above. But the actual source could be a cracked external wall, a leaking terrace downpipe, or even a failed terrace waterproofing membrane two floors up.
This is why thermal imaging is not just a diagnostic tool. It is a legal safeguard. If your society sends you a 47(c) notice and you can prove with a thermal scan that the source is external, the society cannot force you to pay. The notice should be reissued under 47(a) and the society bears the repair cost.
You can see real examples of how this works on our YouTube channel, where we document actual leak detection cases.
The Supreme Court Position on Upper-Floor Leakage
The Supreme Court has held that the flat owner above is liable for water leakage damage to the flat below, unless the leakage is caused by structural defects in the building. This means if your bathroom waterproofing has failed and is leaking into the flat below, you are responsible. But if the leakage is due to a structural crack, external wall seepage, or common plumbing, the society must fix it under 47(a).
The problem is that most disputes never get to court because neither side has proper evidence. The society sends a notice, the flat owner disputes it, and nothing gets fixed for months while the damage worsens. During monsoon, this delay can cause extensive damage to both flats.
What to Do Before Signing Any Repair Contract
If it turns out the leakage is from your flat and you need to repair it:
- Get the source identified first with non-invasive detection. Do not let a contractor start breaking tiles based on guesswork.
- Insist on a written scope of work specifying which materials will be used, the warranty period, and whether a flood test will be conducted after repairs.
- Ask for a post-repair thermal scan to confirm the leakage is fully resolved. This gives you documented proof that you have resolved the issue, which protects you from future disputes.
- Keep all reports and correspondence. If the downstairs neighbor raises the issue again, your documentation proves you acted properly.
PS Group offers a complete leak detection to repair pipeline. We start with thermal imaging diagnosis to identify the exact source, then carry out targeted waterproofing repairs only where needed. No unnecessary demolition, no guesswork, no repeated disputes.
Your Rights, Summarized
You have the right to a proper written notice citing the specific bye-law. You have the right to a joint inspection before any repairs begin. You have the right to demand source identification before paying for repairs that may not be your responsibility. And you have the right to documented proof that the repair has resolved the issue.
If your society has sent you an inter-flat leakage notice and you want to get the source properly identified before anyone starts breaking tiles, contact PS Group or message us directly on WhatsApp. We will run a thermal imaging scan on both flats and give you a written report that settles the dispute with evidence, not accusations.
You can also follow us on Instagram and LinkedIn for more housing society maintenance tips throughout the monsoon season.
