[Diagnosis of drainage culverts after earthquakes] Did the earthquake cause misalignment and leakage of drainage pipes in buildings? How to use pipe endoscopes for non-destructive testing and repair methods for water pipes in Shuangbei Apartment without demolition of walls

Undercurrent after the earthquake: Invisible drainage pipe misalignment and leakage hazards

In many old apartment buildings in the greater Taipei area, the drainage pipes, sewage pipes and excrement pipes are mostly buried in RC structural walls or pipe rooms. When a strong earthquake shakes, relative inter-story displacements will occur between the floors of the building. If the buried hard drainage pipes (such as PVC pipes) lack sufficient lateral displacement compensation space, it is easy to cause shear dislocation, degumming or extrusion rupture at the "pipe joint" where the pipes pass through the floor. Since there is no water pressure in the drain pipe when not in use, such ruptures often do not cause water spray immediately. Instead, when residents upstairs take a shower or flush the toilet, wastewater will leak into the gaps between the wall and structure in trace amounts from the misalignment gaps. In the long run, it not only causes wall cancer and steel bars to corrode and swell, but also often triggers legal lawsuits between neighbors upstairs and downstairs alleging water leakage, which greatly damages the commercial rental value and liquidity of the house.

High-tech non-destructive diagnosis: Drain Camera penetrates every hole

Traditional leak detection often requires knocking out large areas of tiles and concrete walls, which not only has a long construction period and high noise, but is also a disaster for store operations or residential buildings under lease. Modern hydropower leak detection projects have fully introduced "pipeline endoscope non-destructive testing". The plumber technician will extend the flexible wire equipped with a high-resolution waterproof lens, LED auxiliary light source and distance counter into the pipeline from the bathroom floor drain, toilet drain outlet or attic vent. The real-time picture inside the pipe captured by the camera will be transmitted to the handheld monitor, and you can clearly see whether there are cracks in the pipe wall, whether the joints are misaligned and separated, and even whether there is cement mortar blockage. Through the pipeline positioning probe (Sonde), technicians can accurately calibrate the dimensions of damaged points on the ground to achieve precise excavation and avoid CapEx waste caused by blindly knocking on walls.

Efficiency of flipping repair: Pipe Relining without wall removal

For minor cracks or joint debonding of water supply and drainage pipes buried in structures, the most innovative construction method in the greater Taipei area is the "wall-free water pipe perfusion method", also known as non-destructive lining repair. This construction method does not require knocking down bricks and demolishing walls. Plumbing technicians will first drain the leaking pipe section and dry it inside the pipe, and then inject special polymer epoxy resin (Epoxy) or polyurethane sealant. Use air or water pressure to press the repair agent evenly against the pipe wall, filling all tiny cracks and misaligned joint gaps, and forming a new layer of chemical corrosion-resistant, highly elastic and seamless lining on the inner wall of the pipe. This construction method shortens the wall knocking and reconstruction project that originally took one to two weeks to 1 to 2 days and is the best repair option for commercial building renovations and boutique property operators when maintenance operations are not interrupted.

Business asset protection: preventive pipeline inspection and transaction security

In the transactions of antique houses or entire commercial property acquisitions (Property Acquisition) in Taipei and New Taipei, senior investors and asset management companies usually include "concealed engineering health inspection clauses" in the contract. Through a professional home inspection team to conduct an endoscope inspection of the whole house's drainage pipes after an earthquake or before a transaction, the risk of damaged pipes in the walls and hidden water seepage in the structure can completely eliminate the risk of building a dangerous building. Completing preventive pipeline maintenance and pipeline filling and reinforcement before decoration construction can effectively ensure property rental income for decades to come and avoid neighbor damage lawsuits. It is a standard operating procedure for precise risk control in real estate business.

The latest standards for catching leaks and regulatory responsibilities in Shuangbei collective housing (2025-2026 practice)

According to Article 10 of the "Apartment Building Management Regulations" of the Ministry of the Interior and the trend of civil water leakage judgments in Shuangbei District Court in recent years, most water leakage disputes in old collective housing focus on the identification and definition of "exclusive parts" and "common parts". The roof platform and the public pipes are jointly owned by all separate owners, and the repair costs should be shared by public funds or all residents in proportion to their shares according to law; if the water supply and drainage pipes inside the floor slabs on the upper and lower floors are damaged, the pipes will be borne exclusively by the users or shared by the upper and lower floors.

At the engineering and technical level, modern professional leak detection has fully introduced non-destructive scientific testing, including "FLIR high-resolution infrared thermal imaging camera" (locating temperature difference leakage paths), "high frequency moisture meter" (measuring the moisture content of deep structures) and "pipeline air pressure and water pressure pressure test" (determining whether hot and cold water pipes are leaking). During construction, do not directly apply elastic cement or oil-based paint on the wet cement layer to seal it. Otherwise, the thermal expansion of internal water vapor will quickly cause the coating to blister and peel off, resulting in more serious powdery wall cancer. The standard construction method must first completely eliminate the water source, wait until the moisture content of the cement structure drops below 8%, and then apply the negative pressure resistant silicic acid permeability crystallized waterproof layer.

Recommendations on independent certificate storage and compensation process for water leakage repair

1. Take photos and videos as evidence immediately: Use rulers to record the leakage range, frequency of water discharge, direction of water mark diffusion, and keep time stamps.
2. Written notification and coordination survey: Officially notify the neighbors through the management committee or a certified letter, and agree on a professional third-party leak detection and appraisal unit recognized by both parties to conduct an on-site survey.
3. The contract states the warranty terms: When signing the contract for the project, be sure to clearly specify the waterproofing warranty period (usually 1 year for partial repairs, and 2 to 5 years for the whole room or roof re-construction), and specify the water test acceptance criteria (such as a 48-hour water storage test in the bathroom shower area) to protect your own asset rights.