Coimbatore sits between the Western Ghats and the Nilgiris, which means the northeast monsoon (October–December) and southwest monsoon (June–September) both affect the city — though the northeast monsoon brings the heavier rains. When they arrive, they arrive fast. One week of heavy rainfall can turn a minor crack in your roof into a major repair job.
The difference between a comfortable monsoon and a nightmare one is usually the preparation you do in May and June. Here's a complete checklist.
Roof and Ceiling
Check for cracks and loose material
Walk the roof (carefully) or have someone do it. Look for: hairline cracks in the concrete, loose or broken tiles, gaps around AC units or exhaust vents, and any area where the waterproofing membrane has bubbled or peeled. Even a 2mm crack can let in significant water under monsoon conditions.
Check ceiling corners inside
Water stains in the upper corners of rooms are the most reliable indicator of an existing leak. They might be dry in summer, but they'll activate the moment the rains start. If you see any, trace them up — the entry point on the roof is usually directly above.
Waterproofing coat
If your terrace waterproofing is more than 3 years old, it's worth applying a fresh coat before the rains. Liquid waterproofing applied in hot, dry weather bonds better than coatings applied on damp surfaces. This is a job most homeowners can do themselves with a roller and a good elastomeric waterproofing product from a hardware store.
Drainage and Plumbing
Blocked drainage is the cause of most monsoon flooding, and it's entirely preventable.
- Clear roof drain covers of leaves, dust, and debris — check that water flows freely
- Check balcony drains: pour a bucket of water and watch it drain. If it pools, the drain is partially blocked
- Inspect external pipes for cracks, loose joints, or rust damage
- Test internal drains for slow drainage — a drain that's slow in summer will overflow in the monsoon
- Clear the area around ground-floor drainage outlets of soil and plant growth
A drain that takes 60 seconds to clear a bucket in dry weather will take 10 minutes in the monsoon — and by then, your balcony is flooded. Clear drains before the rains, not during.
Walls and Waterproofing
External wall cracks
Look for hairline cracks on external walls, especially around window frames, AC installation points, and where pipes enter the building. Fill them with a good exterior crack filler before the rains — most products need 24–48 hours to cure fully, so apply them on a dry day with no rain forecast.
Window and door seals
Run your hand along window frames on a windy day. If you feel a draught, water will get in during rain. Silicone sealant is cheap and effective — reseal any gaps around frames and along the bottom of sliding windows.
Electrical Safety
Water and electricity are the deadliest combination in a monsoon. Take these steps seriously:
- Ensure all outdoor sockets have proper weatherproof covers — check that the covers seal completely
- If your main switchboard is near an external wall or in a location where rain might reach it, have an electrician assess the positioning
- Test all MCBs (Miniature Circuit Breakers) — they should trip when tested and reset cleanly
- Check that all electrical fittings in bathrooms are rated for wet areas
The Rest of the Checklist
- Paint: If external paint is peeling, water will penetrate the wall. A coat of waterproof exterior paint before the monsoon protects the structure
- Garden and landscaping: Trim branches overhanging the roof. Clear gutters of leaf build-up
- Sump and overhead tank: Check for cracks and ensure lids are secure to prevent contamination
- Pest inspection: The monsoon drives cockroaches, termites, and rodents indoors. A pre-monsoon pest treatment is more effective than one done after they've already entered
If this list feels overwhelming, Working Class offers a pre-monsoon home inspection where one of our professionals checks all of these items and gives you a prioritised list of what needs attention. Book a home inspection before June ends.
Frequently Asked Questions
When should I start pre-monsoon repairs in Coimbatore?
April and May are the best months — the weather is dry, materials cure quickly, and contractors have availability. By June, demand spikes and many materials need dry conditions to apply properly.
Can I apply waterproofing myself or do I need a contractor?
Terrace waterproofing using liquid elastomeric products is manageable as a DIY job for small areas. For large terraces or areas with significant cracking, a contractor with proper application equipment will give better results and coverage.
My walls get damp from inside during rain. Is that a roof issue or a wall issue?
Dampness on upper sections of walls usually points to a roof or parapet issue. Dampness on lower sections of external walls often indicates water rising from the ground (rising damp) or penetrating through cracks. Both need professional diagnosis — the fix is different for each cause.