Every Mumbaikar has a monsoon wall. It is the one that develops a faint grey bloom sometime in July, then a map of brown continents by August, and by September has a patch of paint that sounds hollow when you tap it. Ours faces west, towards the sea and the weather, and I have come to think of it as a barometer with opinions.
The rains are the best and worst of living here. The city turns green overnight, the heat breaks, and the sound on a tin awning at 2 a.m. is one of the finest things Mumbai has to offer. But four months of near-constant humidity is hard on buildings, and harder still on buildings that were not maintained in the dry months. Most of what goes wrong in a flat during the monsoon was decided in March, April and May.
Why Mumbai buildings leak
Water gets in through a handful of predictable routes. The terrace is the big one: a flat roof with cracked or ageing waterproofing will send water down into the top-floor flats, and sometimes further, through the slab and along the walls. External walls are the next culprit. Hairline cracks in plaster, gaps around window frames, and poorly sealed joints where an air-conditioner pipe or a cable enters the wall all let driven rain in, and the wind off the sea drives it hard.
Then there is plumbing. Many older buildings have drainage and water pipes running down the outside of the building, and a leaking joint behind a bathroom wall will show up as damp in the bedroom next door, and in the flat below. It is worth knowing that not every monsoon stain is caused by rain. If a patch is damp in February, the problem is a pipe, not the weather.
What to do before June
The single most useful thing you can do is walk around the flat in April with a torch and a critical eye. Look for the following:
- Cracks in the external plaster around your windows, visible from inside if you lean out, or better, from the building opposite.
- Old, dried-out silicone or putty around window frames and glass panes. It shrinks and crumbles in the sun and should be redone every couple of years.
- Bathroom tile joints that have lost their grout, especially around the floor trap and the base of the shower wall.
- Any existing stain, even a faded one. Old stains usually mark a route the water already knows.
Resealing windows and regrouting bathrooms is cheap and can be done by a competent local contractor in a day or two. External wall work is a different matter, because it usually needs scaffolding or a rope-access crew and must be coordinated with the society. That is why it has to be raised early. Contractors in Mumbai are booked solid from April, and nobody sensible does exterior waterproofing once the rains have started; the surfaces must be dry for most coatings to bond.
Society versus owner: who fixes what
This is where most monsoon arguments happen, usually in a WhatsApp group at 11 p.m. The broad principle in Maharashtra's cooperative housing societies is that the society is responsible for the structure and the common areas, and the member is responsible for the inside of their own flat. The terrace, the external walls, the common drainage lines and the building's structure fall to the society. Leaks from your own bathroom, your internal plumbing, or alterations you have made fall to you.
In practice the lines blur. Water from a cracked external wall damages your internal plaster, and someone has to decide whether the repainting is the society's cost or yours. A leak from the flat above is the upstairs owner's responsibility if it comes from their bathroom, but proving that can take a week of polite visits and one less polite one. The model bye-laws that most societies adopt set out the division of repairs in some detail, and your society's own adopted bye-laws are the document that actually governs you. Read the repairs section before you need it. If a dispute escalates, the registrar of cooperative societies for your area is the formal route, though a well-minuted managing committee meeting usually resolves things sooner.
Tenants are in a different position: your landlord is your counterparty, not the society. Report leaks in writing, with photographs and dates, and do it early. It protects your deposit and it gives the landlord time to chase the society.
Terrace repairs and the society meeting
If your building has a leaking terrace, the fix is usually a fresh waterproofing treatment, and for a building of any size the cost runs into lakhs. That means it goes to the general body, it gets quoted by more than one contractor, and it is funded from the repair fund or a special contribution. Top-floor residents feel the problem most keenly and often end up pushing for it, which is fair enough; everyone else should remember that water in the slab eventually becomes a structural problem for the whole building.
A few things are worth asking any contractor: what system they propose, how many years of guarantee they will give in writing, and whether they will return to inspect after the first monsoon. A treatment done in a rush in late May, on a surface that has not been properly cleaned and repaired, is money poured off the edge of the roof.
Living with the damp
Even a well-sealed flat will be humid from June to September. Mould loves still air, so the first defence is ventilation. Open windows on the leeward side when it is not pouring, run exhaust fans in bathrooms and the kitchen, and keep a little gap behind wardrobes and beds placed against external walls. Leather bags, shoes and books are the usual victims; keep them out of closed cupboards on external walls, and air them on the rare sunny afternoon.
A dehumidifier is the single purchase I would recommend to anyone new to the city. A mid-sized domestic unit will pull several litres of water out of the air a day in a Mumbai July, which is a startling thing to see in the tank the first time. Run it in the bedroom with the door closed, or in a wardrobe room, and empty it daily. Air-conditioners also dehumidify as a side effect, and many have a dry mode that does just that without chilling the room.
Then there is laundry. Clothes hung indoors in August do not so much dry as become slightly less wet over three days, acquiring a smell on the way. The standard Mumbai answers are a ceiling-mounted pulley rack, a fan pointed at a clothes horse, a spin cycle run twice, and, increasingly, a dryer, for those with the space and the electricity budget. A pinch of patience helps too. Towels are the hardest; I rotate more of them in the monsoon than seems reasonable.
For mould that has already appeared, wipe it off with a diluted vinegar or a mild bleach solution, dry the surface thoroughly, and fix the source of moisture before repainting. Anti-fungal paint over a wet wall only buys a few weeks.
The monsoon wall, revisited
Our west wall got its proper treatment two summers ago, after three years of me raising it at society meetings and one especially wet August that brought a patch through to the top-floor flat next door. The external plaster was repaired, the window frames resealed, the whole face coated. Last monsoon the wall stayed white. I found I missed it a little, the way you miss a difficult relative who has finally moved to Pune.
The real lesson was not about paint. It was that the monsoon in Mumbai is a shared problem that rewards people who plan in the dry months and talk to their neighbours before things go wrong. Walk around your flat in April, read your bye-laws once, and book the contractor early. Then, in July, you can listen to the rain on the awning and simply enjoy it.
