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Water Leakage Case Study at Tak Shun Garden, Ho Man Tin: Upper-Floor External Wall Seepage and Window Frame Seal Failure

A 20-year water seepage mystery resolved. The affected unit suffered from exposed, rusted rebar in room beams and a deformed, unclosable aluminum window. Using "External Wall Spray Testing," Infrared Thermography, and Moisture Comparative Analysis, Silver Surveyors proved that water penetrated through the upper-floor external wall via the window frame. Furthermore, waterproofing defects were found in the upper unit's altered bathroom piping. Claimed Amount: HK$134,772.

Silver Surveyors

8/7/20266 min read

A 20-Year Leakage Nightmare – The Source Was Right Outside the Window

“This problem has been troubling me for 20 years.”

The owner of Flat C, 19th Floor, Tak Shun Court, Ho Man Tin, stared at the ever-expanding water stain on his bedroom ceiling, his voice filled with helplessness. For two decades, he had watched the paint peel off piece by piece, the concrete on the beam crumble bit by bit, and the steel reinforcement gradually become exposed and rusty. He even noticed that the aluminium window in the bedroom could no longer close properly because the beam had deformed.

He called in workmen. He tried repairing it himself. But the leakage never stopped. Every time it rained, water stains reappeared on the walls, the rust on the beam grew darker, and the hollow sound from the ceiling became more pronounced.

“I’ve lived here for so long. Do I have to watch my home rot away forever?”

That feeling of seeing your home slowly destroyed by water, with no way to stop it – we understand it completely.

A Scientific Investigation That Solved a 20-Year Mystery

On 23 June 2026, the expert team from Silver Surveyors arrived at the subject flat to conduct a comprehensive technical inspection. We deployed multiple professional methods, cross‑validating every finding and leaving no detail unchecked.

What did we discover?

1. Infrared Thermography Revealed Concealed Moisture Zones

Significant moisture retention was detected in the bedroom ceiling, beam, and wall (Bedroom 1), as well as in the wall of Bedroom 2. Most notably, the beam near the window frame showed extensive dark blue low‑temperature areas – clear evidence of massive water accumulation, marking the core of the leakage.

2. Moisture Meter Testing Confirmed the Severity

We set up multiple moisture measurement points across all affected areas and conducted two critical tests:

Test 1 (External Wall Water Spray Test): Simulated rainfall by spraying the external wall for 30 minutes.

Test 2 (Window Frame Water Spray Test): Sprayed the bedroom window frame for 30 minutes.

The results were telling: after Test 1, moisture readings at all affected locations rose significantly; after Test 2, there was no further change. This meant the source of leakage was the external wall, not the window frame itself.

For example, the moisture reading at beam position B1 was already 78.9% before the test and jumped to 89.3% after spraying. Wall position C11 surged from 38.8% to 78.1% – clear proof that water was entering the interior through the external wall.

3. Water Sample Analysis Ruled Out Drainage Pipes

We collected water samples from all four affected areas. Results showed a salinity of 0.00 p.p.t and a negative ammonia test in every sample – confirming the infiltrating water was fresh water (rainwater or tap water), not sewage or drainage.

4. Visual Inspection Documented the Extent of Damage

Our inspectors found alarming conditions:

Bedroom 1 ceiling: hollow/delaminated areas, cracks, peeling paint and plaster

Bedroom 1 beam: water stains, concrete spalling, exposed and corroded steel reinforcement – a serious structural safety warning

Bedroom 1 wall and Bedroom 2 wall: water stains, cracks, peeling paint and plaster

Bedroom 1 aluminium window: deformed due to beam spalling, unable to close

Crucially, the inspection also revealed that the upper‑floor unit (Flat C, 20/F) had relocated its bathroom directly above the subject flat’s bedroom, raising suspicion that the pipe modification work had not been properly waterproofed.

Comprehensive Conclusion: Upper‑Floor External Wall Leakage + Failed Window Seal

By synthesising all test results, we reached the following conclusion:

There is evidence and indication that the upper‑floor external wall is leaking, with water passing through the bedroom beam and above the window frame, then spreading to the bedroom ceiling, beam, wall, and the wall of Bedroom 2.

In addition, the bedroom window frame had deformed over time due to structural stress, losing its seal and further worsening the leakage.

“So it was the external wall all along… plus the leftover problem from the upstairs bathroom renovation.”

When we presented our findings to the client, the mystery that had haunted him for 20 years finally made sense. Those countless sleepless nights now had a clear answer.

How Much Damage Was Done? A Clear Assessment

Based on our detailed calculations, the total loss and estimated repair cost for the subject flat amounted to:

HKD $134,771.76

This covered:

Bedroom 1 ceiling (approx. 50 sq. ft.): cutting out loose concrete, anti‑rust treatment for rebar, replastering and emulsion paint

Bedroom 1 beam (approx. 40 sq. ft.): concrete repair, rebar anti‑rust treatment and structural strengthening

Bedroom 1 wall (approx. 30 sq. ft.) and Bedroom 2 wall (approx. 10 sq. ft.): replastering and painting

Replacement of the deformed aluminium window and waterproof sealing around the frame

Inspection and, if necessary, repair/replacement of the affected electrical system

Debris removal and final cleaning

Note: Due to prolonged leakage, the beam’s steel reinforcement has already begun to corrode. If left untreated, this could compromise structural safety. We recommend first repairing the external wall and the upper‑floor pipe leakage source, and only proceeding with interior restoration once the leakage has been confirmed stopped.

What This Case Teaches Us

Leakage problems don’t always develop overnight. Over 20 years, a tiny water entry point can evolve into corroded rebar and structural damage. And the most frustrating part is – you simply cannot see the source with the naked eye.

At Silver Surveyors, we let science speak and integrity guide us. Through external wall water spray tests, infrared thermography, moisture comparison analysis, and water sample testing, we cross‑validate every finding to uncover the truth.

If you are facing a similar ordeal – damp walls, peeling ceilings, cracked beams, or exposed rebar – don’t wait any longer. Let our expertise and science identify the root cause and protect your home.

Expert Qualifications Endorsement

This report was signed and confirmed by Mr. Leung Ka Chun, Managing Director of Yin Jin Consultants & Gongzheng Limited. As a Chartered Institutional Surveyor (MRICS), Chartered Builder (MCIOB), and Chartered Building Engineer (MCABE), Mr. Leung possesses extensive experience in building diagnostics and surveying, ensuring the professional authority of the investigation.

Silver Surveyors | Precision in Investigation, Integrity in Service

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