Warehouse or industrial roof leaking
On a large-span roof the leak is more often at the gutters, valleys and downpipes than in the roof sheet itself. Mumbai rainfall intensity regularly exceeds what older drainage was sized for, so water backs up and enters at the laps.
Not an emergency, but it will get worse and more expensive with every monsoon it survives.
Probable causes, ranked
Ordered by how often we find each one to be the actual source. The 'tell' is what distinguishes it from the others.
- 01most common
Blocked or under-sized gutters and downpipes
The tell — Leakage worst during heavy downpours and near gutter lines.
TPO Membrane Waterproofing → - 02common
Failed laps and fixings on sheet roofing
The tell — Drips follow fixing lines or sheet overlaps.
APP Membrane Waterproofing → - 03common
Corrosion of a metal deck
The tell — Rust perforation visible from below.
Polyurea Waterproofing → - 04less common
Failed roof-light and penetration seals
The tell — Leakage traces to specific roof-light positions.
TPO Membrane Waterproofing →
Sixty seconds, before you call anyone
- Photograph it while it is actively wet. A dried stain tells a surveyor far less than a running one.
- Note whether it worsens with rain or with usage. Rain-linked points to the building envelope; usage-linked points to plumbing. This single distinction settles most arguments about responsibility.
- Check the area directly above and beside the damage, not only below it. Water travels along a slab before it drops.
- Look specifically for the tell of the most likely cause: leakage worst during heavy downpours and near gutter lines.
- Do not chip into saturated plaster or paint over a damp patch. The first risks bringing material down; the second destroys the evidence needed to trace the path.
What it becomes if you leave it
In a warehouse the building repair is usually the smaller number. Stock loss from a single heavy downpour over racking frequently exceeds the cost of the roof work several times over.
Often seen alongside this
- Water standing on the terrace after rain
Water still standing on a terrace 24 hours after rain means the surface has no effective fall to the outlets.
- Industrial floor breaking up under traffic
An industrial floor fails when the surface was specified for chemical resistance but not for mechanical loading, or when the substrate beneath was never properly prepared.
Warehouse or industrial roof leaking — questions we get asked
What is the most likely cause of warehouse or industrial roof leaking?
Blocked or under-sized gutters and downpipes. The sign that points to it is: leakage worst during heavy downpours and near gutter lines. That said, the ranking here is a starting point — the actual source is confirmed by survey, because more than one of these can be true at once.
What happens if I leave it?
In a warehouse the building repair is usually the smaller number. Stock loss from a single heavy downpour over racking frequently exceeds the cost of the roof work several times over.
Can I diagnose this myself before calling anyone?
Partly, and it is worth doing. Photograph it while it is actively wet, note whether it worsens with rain or with usage, and check the area directly above and beside the damage. That single rain-versus-usage distinction narrows the cause more than anything else you can do in sixty seconds.
How urgent is this?
Act this season. Not an emergency, but it will get worse and more expensive with every monsoon it survives.
Send us a photograph and we will tell you what we think it is
WhatsApp a photo taken while it is wet, with a note on whether it tracks with rain or with usage. That is usually enough for a first opinion, and the site inspection that follows is free.
Mon–Fri 08:00–18:00 · Sat 09:00–16:00 · Jogeshwari West