Balcony Leaking Into the Unit Below (Condo) — Causes, Fixes & Cost in KL
Your downstairs neighbour reports water dripping from their ceiling on the same footprint as your balcony above.
Estimated professional fix: RM 800–RM 6,500+ depending on membrane state
In a condo, a leaking balcony is not just a leak — it is a legal relationship with the unit below. Under most Malaysian JMB rules the strata unit owner is responsible for the waterproofing of their own balcony, which means the downstairs neighbour's ceiling stain is your invoice, and the clock starts when the JMB serves the repair notice. The physical story is usually one of four: the acrylic or cementitious membrane has aged and cracked, the tile grout has let rain through for years, the balcony drain is blocked and water pools against the slab, or a hairline crack in the concrete is doing slow work during every monsoon. The good news: most of these can be fixed without hacking your tiles — grout the slab from below, or strip and re-membrane only the failed zone.
Common causes
Professional solutions
Safe DIY checks first
- 1Do a ponding test: hose the balcony, let it pool for 30 minutes, and check the unit below — a new dark spot marks the active path
- 2Check the balcony drain: run water and watch it go; if it pools, the drain is the first thing to fix
- 3Tap-test the balcony floor tiles — a hollow ring around a wet zone means the membrane has failed at that spot
- 4Photograph the downstairs damage with dates, and keep the JMB correspondence — the paper trail is what settles the liability question later
When to call a pro
What affects the cost
PU grouting the slab from below — with the downstairs owner's permission, no hacking of your tiles — starts around RM800–RM2,500 depending on the crack line. A partial re-membrane of the failed zone runs RM2,500–RM4,500. Full tile-hack, new membrane, and re-tiling of the whole balcony is the RM4,500–RM6,500+ job, typically 3–5 working days. We do a ponding test first so the method matches the actual leak path, and the waterproofing carries the standard written warranty.
How to prevent it
Related service
This problem usually connects to Waterproofing & Leak Repair Services. Review service scope, pricing, warranty, and process before booking.
View Waterproofing & Leak Repair ServicesFAQs
Am I liable for the downstairs unit's damage?
Under most Malaysian JMB rules yes — the strata unit owner is responsible for their own waterproofing. Fix urgently and document the repair for future claims.
Can you PU grout from the downstairs unit without hacking my balcony tiles?
Often yes — with the downstairs owner's permission, we grout the slab from below and avoid touching your tiles. Success rate is high for hairline cracks.
How long does a balcony re-membrane take?
Full tile-hack + new membrane + retile is typically 3 to 5 working days for a standard balcony.