Signs Your Balcony Waterproofing Has Failed
Balconies usually tell you they’ve failed well before anyone connects the signs.
In an apartment, the neighbour below often notices first. In a house, it turns up as a damp patch in a room nobody associates with the balcony. Here’s what to look for.
On the balcony itself
- Tiles lifting, drumming or cracking, often along one line – the bed underneath is saturated and the adhesive is letting go.
- White chalky residue through the grout. Efflorescence. Water is moving through the structure and carrying salts to the surface.
- Water still sitting there a day after rain. The falls aren’t draining, and standing water finds every weakness.
- Grout washing out or looking permanently dark and damp.
- The outlet not clearing – or no visible outlet at all.
Underneath and around it
- Staining on the ceiling below, or in the unit downstairs.
- Paint bubbling or render blowing on the wall beneath the balcony.
- Rust staining or spalling concrete at the balcony edge – that’s water reaching the reinforcement, and it’s the serious one.
- Damp inside around the door threshold.
- Musty smell in the room below that doesn’t clear.
The one to act on quickly
Rust staining or concrete flaking at the edge means water has already reached the steel. Rusting steel expands, and expanding steel breaks concrete apart from the inside.
At that point it stops being a waterproofing job and starts being a concrete repair job, which costs considerably more. Caught early it’s a membrane. Left long enough it’s structural.
What it doesn’t automatically mean
Not every wet patch below a balcony is a failed membrane. We’ve traced plenty back to the door threshold, a window above, a planter box, or a drainage outlet that was blocked rather than defective.
Which is worth knowing, because those are much smaller jobs. Find out what’s actually happening before anyone starts pulling up tiles.
Need someone to look at it?
We inspect before we quote, across Sydney. Call 0450 679 512 or email sam@sydneychoicewaterproofing.com.au.
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