What are the signs a balcony is leaking?
- Water stains, drips or bubbling paint on the ceiling or wall of the unit below, often worse after heavy rain
- White powdery deposits (efflorescence: salts carried out by water) coming out of the grout lines
- Cracked, crumbling or missing grout, and gaps in the sealant where the tiles meet the walls
- Hollow-sounding ("drummy") tiles when you tap them
- Damp carpet, a musty smell or mould in the room next to the balcony door
Where does the water actually get in?
- Grout lines. Old cement grout is porous. Once it cracks, every rain soaks straight into the bed below the tiles.
- Perimeter joints. The sealant where the tiles meet the walls breaks down in the sun and pulls away.
- The door threshold. Water pools against the sliding door and gets under the frame.
- Balustrade posts and other penetrations. Anything fixed through the tiles is a gap waiting to leak.
- The membrane, falls or drain. If the waterproof membrane under the tiles has failed, the floor doesn't slope to the drain properly (poor "falls"), or the drain itself is leaking, sealing the surface won't fix it alone.
Grout leak or membrane failure: how can you tell?
You can't always tell from the ceiling below, which is why the balcony needs to be inspected, not just the damage. As a rough guide:
| Points to grout and sealant | Points to membrane, falls or structure |
|---|---|
| Cracked or missing grout, open perimeter joints | Water still coming through after the surface has been sealed |
| Leak shows up after rain and dries out in between | Constant damp, even in dry weeks |
| Efflorescence in the grout lines | Many drummy or loose tiles across the balcony |
| Tiles are firm and level | Water pooling because the floor doesn't drain |
| Cracked screed or visible structural cracks |
If it's the grout and sealant, an epoxy regrout and reseal is the least disruptive fix. If it's the membrane or the falls, the balcony will usually need to be rebuilt, and we'll tell you that before you spend money with us.
Who organises the repair in an apartment block?
In most Melbourne apartment buildings, balcony works need owners corporation approval before anything starts, and who pays depends on your building's plan of subdivision and rules. Talk to your strata manager first, and let the owner below know what's happening. We can provide a written scope of work and a fixed quote for the committee or strata manager.
How much does it cost to fix a leaking balcony in Melbourne?
The Seal Guys' 2026 prices for balcony epoxy regrouting and resealing:
| Balcony size | Price (ex GST) |
|---|---|
| Up to 5 m² | from $2,200 + GST |
| 6–8 m² | from $2,400 + GST |
| 9–12 m² | from $3,100 + GST |
| 13–20 m² | from $4,000 + GST |
| Over 20 m² | individually quoted |
Small tiles and mosaics, existing epoxy grout, drummy tiles, upper-level access and extra work (door thresholds, drains, balustrade posts) change the price. Send photos and rough measurements for a fixed quote. A full balcony rebuild usually costs many times more and takes much longer.
What does an epoxy regrout and reseal involve?
- Remove the deteriorated grout and failed perimeter sealant
- Clean out the joints and remove efflorescence where needed
- Regrout with Mapei Kerapoxy epoxy grout, which is non-porous and doesn't need sealing
- Reseal the perimeter, movement joints, door threshold and balustrade posts, as quoted
- Final clean
Balcony work needs dry weather before and after, so we book around the forecast and tell you how long to stay off the balcony while the epoxy cures.
Warranty: 10-Year Warranty on eligible epoxy re-grouting work, subject to terms.
What our balcony customers say
“Very happy with the re-grouting work completed on our bathroom and balcony. … everything was left clean and tidy.”
“…fixed my leaking balcony very quickly. They also helped with bathroom waterproofing prevention and came back afterwards to check everything was working well.”
Balcony leak FAQs
Can a leaking balcony be fixed without removing the tiles?
Often, yes. If the water is getting in through the grout, perimeter sealant, door threshold or balustrade posts, an epoxy regrout and reseal stops it without lifting tiles. If the membrane has failed, the tiles will usually need to come up.
Will regrouting stop the leak into the apartment below?
If the grout and sealant are where the water gets in, yes. Regrouting doesn't replace a failed membrane, which is why we inspect before we quote.
Why is there white powder coming out of my balcony grout?
That's efflorescence: salts dissolved by water moving through the grout and tile bed, left behind when it dries. It's a sign water is getting in.
Do I need owners corporation approval?
In most apartment buildings, yes. We can give your strata manager a written scope and quote.
How long does it take?
It depends on the size and condition of the balcony, and we need dry weather. We'll give you a time frame with your quote.
How much does it cost?
From $2,200 + GST for balconies up to 5 m². See the price table above.
Send 3–4 photos of the balcony (the whole area, a close-up of the grout, the door threshold and any damage below) with rough measurements to 0458 679 629 or through the quote form. We'll reply with a fixed price.
Full prices: shower regrouting cost in Melbourne