Darlinghurst strata balcony leak repair: case study

Strata balcony leaks in Darlinghurst: fixing a failed earlier repair

Ceilings were staining in the units below the balconies of a Darlinghurst strata block, even though another contractor had repaired the balconies a few years earlier. We regrouted, resiliconed and sealed all three balconies over 5 days, without removing the tiles. After pressure testing showed no leaks, the strata manager signed off the work.

The job at a glance

Location: Darlinghurst, NSW 2010
Property: strata block of units
Problem: water staining on the ceilings beneath the balconies, after an earlier repair by another contractor
Balconies: 3
Work: degrouted and regrouted all three balconies, resiliconed all perimeters and door junctions, and sealed all three
Time on site: 5 days for all three balconies
Back in use: each balcony after 24 hours of curing
Tiles removed: none
Testing and sign-off: pressure tested with no leaks, then signed off by the strata manager
Completed: September 2026

Before: Large terracotta-tiled strata balcony with worn grout and a patchy, poorly finished perimeter joint — Balcony 1: worn grout and a patchy earlier repair before; regrouted, resiliconed and sealed after

After: The same balcony regrouted with clean white grout, resiliconed around the edges and sealed to a glossy finish — Balcony 1: worn grout and a patchy earlier repair before; regrouted, resiliconed and sealed after

During: The same balcony with all the old grout raked out of the joints, ready for regrouting — Balcony 1 mid-job: every joint raked out before regrouting

Before: Second balcony with weathered grout and a failed, messy joint along the brick wall — Balcony 2: weathered grout and a failed joint along the wall before; regrouted and sealed after

After: The second balcony with new grout, resealed edges and a sealed finish — Balcony 2: weathered grout and a failed joint along the wall before; regrouted and sealed after

Before: Narrow side balcony with dark, failing silicone along the brick walls and tired grout — Balcony 3: failing silicone along the walls before; resiliconed, regrouted and sealed after

After: The narrow balcony regrouted, resiliconed along the walls and sealed — Balcony 3: failing silicone along the walls before; resiliconed, regrouted and sealed after

The problem

Water stains were appearing on the ceilings of the units underneath the balconies. Another contractor had repaired the balconies a few years before, so the owners corporation was dealing with a repeat problem, and owners whose ceilings were marked.

What we found

The earlier repair hadn't been prepared properly. The old grout hadn't been fully removed before new material went in, and the perimeter joints along the brick walls, upstands and doors were patchy, with sealant that had split or come away. Water was getting in through the joints and edges and finding its way into the ceilings below.

The tiles themselves were sound, so the balconies didn't need to be stripped back to the slab and rebuilt.

What we did

Raked out the grout from every joint on all three balconies, back to clean, sound edges.
Cut out the old sealant around all the perimeters and door junctions.
Regrouted each balcony completely.
Resiliconed every perimeter and door junction.
Sealed each balcony and left it to cure for 24 hours before residents used it again.
Pressure tested the balconies to confirm they were watertight.

All three balconies took 5 days. We worked through the balconies in turn, so each one was out of use for only a short time.

The result

Pressure testing showed no leaks, and the strata manager signed off the work.

Repeat leaks after an earlier repair?

When a balcony starts leaking again after it's been "fixed", the cause is often preparation: the old grout and sealant weren't fully removed, so the new material had nothing sound to bond to. We prepare every joint properly, test the result and give strata managers the findings, photos and sign-off they need for the committee. We can also issue a compliance certificate for our waterproofing work. See our strata leak repairs

Every building is different. If a balcony needs more than a non-invasive repair, we'll say so at the inspection.