[A big fight over who is responsible for the leakage of the roof on the roof] Shared platform vs. dedicated roof, who should pay for the leakage and repair costs?

The nightmare of water leakage in old apartments in Taipei

During the rainy season or typhoon days in Taipei and New Taipei, the most common neighborhood dispute in old apartments is "water leakage from the top floor." When a fourth-floor resident’s ceiling begins to seep, the wall cancer peels off, or even drips and wets the furniture, the gut reaction is usually to find the owner of the fifth-floor attic to take responsibility. However, rooftop owners often argue: "The roof deck is shared by the entire building, and the leakage is due to the aging of the public waterproof layer. All residents or the management committee should pay for repairs." Both parties disagree, and eventually even go to court. In legal practice, who should be responsible for repairing leaks in the attic? How should the costs be divided?

Regulations decrypted: Shared principles for "rooftops" in the Apartment Building Management Regulations

According to Article 7 of the Apartment Building Management Ordinance, the roof deck is essentially a "common part" and cannot be reserved for exclusive use without the consent of all zone owners. At the same time, Article 10, item 2, of the Regulation states:

"The repair, management, and maintenance of the common parts and the agreed common parts shall be carried out by the person in charge of management or the management committee. The costs shall be paid from public funds or shared by the divided owners in proportion to their share of the shares."

This means that if the water leakage is caused by the "natural aging and cracking of the waterproof layer" on the roof platform, and it is an uncovered public space, the repair costs should indeed be paid by the management committee, or shared by all residents in proportion to their shares, and cannot be imposed on the top floor households.

Key watershed: whether the water leakage is caused by "roof top building"

However, when there is "top floor addition (illegal construction)" on the roof platform, the court's decision logic will undergo a key change. When the court determines liability, the core lies in the "causal relationship between the cause of the water leakage":

• The roof owner can be blamed: If identified, the cause of the water leakage is that the attic roof owner destroyed the original waterproof layer during construction, modified the bathroom pipes without permission, causing leakage, the roof structure was too heavy and the floor slabs were cracked, or the roof roof blocked normal roof drainage, causing rainwater to accumulate and leak. At this time, the leakage responsibility is considered "man-made", and the top owner should bear all repair costs and compensate the downstairs residents for the loss of decoration and furniture.
• Exclusive maintenance responsibility agreed upon: Even if Dingjia is deemed an "existing illegal construction" and demolition is suspended, the owner of Dingjia has actually formed a "dedicated" or "exclusive use" of the roof platform. Court practice often holds that since top households enjoy exclusive use benefits, based on the principle of reciprocity of rights and obligations, they should also bear the responsibility to eliminate infringements for daily maintenance within the exclusive scope and for repairing leaks caused by illegal construction.
• Legal Consequences of Impeding Repairs: If the water leakage is indeed due to the aging of the public waterproof layer, but the owner of the Dingjia House refuses to demolish the illegal construction to facilitate the laying of the waterproof layer by the management committee, or refuses to allow the plumbers to enter and cooperate with the inspection, the downstairs residents can apply to the court to "eliminate the infringement" in accordance with the law and require the Dingjia House owner to demolish the illegal construction that hinders the construction within a time limit. The Dingjia House owner cannot refuse.

Three steps to detect and identify water and electricity leaks: evidence preparation for court offense and defense

If you are a downstairs homeowner suffering from water leakage, be prepared to seek compensation from the roof owner or management committee through legal channels. Do not just rely on your naked eyes to guess. You must complete the following professional evidence gathering steps:

1. Preliminary professional plumber and electricity leak detection: Invite a qualified plumber and electricity dealer or leak detection master to conduct a preliminary inspection. Through the infrared thermal imaging camera, pipeline pressure test (water pressure needle test) and drain pipe color water test, it is confirmed whether the water source comes from the bathroom waterway, drainage holes, or rain seepage from the roof expansion joints.
2. Apply for a third-party professional appraisal: If the two parties have a dispute over liability, they can apply to the "Architects Association", "Civil Technicians Association" or "Structural Technicians Association" for an appraisal of the cause of the leakage. Although the appraisal fee (approximately 50,000 to 150,000 yuan) must be paid in advance by the applicant, this report has extremely high evidentiary power in court, and the losing party can be required to bear the cost after winning the case.
3. Formal written reminder: After obtaining the inspection evidence, send a certificate of deposit letter to the roof owner and the management committee, stating the fact of the leak and the identification results, and limiting repairs within 14 days. If the other party fails to respond within the time limit, you can file a civil lawsuit with the court to request exclusion of infringement and compensation for damages.

Conclusion: Rational negotiation is the most efficient repair guide

Although the law has a clear division of responsibilities, it often takes half a year to two years to fight a civil lawsuit, during which time the leakage problem continues to damage the house. For the roof owner and downstairs neighbors, the most pragmatic approach is to clarify the proportion of responsibilities under the witness of a professional plumber and electricity leak catcher. If water leaks in the illegally built part, the Tingjia household should show sincerity in funding repairs; if the public waterproof layer is aging but limited by the location of the illegal construction, the two parties can agree that the Tingjia household will contribute the majority of the investment and the management committee will subsidize the small part. After all, protecting the structural safety of the house and completely eradicating wall cancer are the best win-win solutions to protect asset value and living quality.

New knowledge on air-conditioning power consumption and Taiwan climate maintenance regulations in recent years (2025-2026 current situation)

With the high temperatures in summer breaking historical records and the adjustment of electricity price structure in recent years, the latest statistics from the Energy Administration of the Ministry of Economic Affairs show that air-conditioning equipment accounts for more than 47% of residential electricity consumption in summer. Many people mistakenly believe that if the air conditioner is not cold, they only need to "replenish the refrigerant." However, in fact, refrigerant is not naturally consumed during normal operation in a closed circuit. If the refrigerant is insufficient, it means that there are micro leaks in the copper pipes or joints. Simply replenishing the air conditioner will only treat the symptoms but not the root cause. Refrigerant leakage will aggravate the high temperature overload of the compressor and shorten its service life.

According to Taiwan's standard operating specifications for air-conditioning projects, it is recommended that professional technicians with a refrigeration and air-conditioning decoration technician license perform "full machine high-pressure water washing and evaporator deep sterilization" every 1 to 2 years for detached air-conditioning indoor units. Especially in the humid summer in the Shuangbei Basin, the air drum and water collection tray are easy to breed black mold and jelly-like biofilm. This is also the main reason for the sour smell in the air-conditioning outlet and the backflow of the drainage pipe. Regular maintenance can maintain CSPF (Air Conditioning Seasonal Performance Factor) level one energy efficiency level, which can save an average household 15% to 20% of air conditioning electricity bills every year.

Autonomous simple maintenance vs professional maintenance safety red line

• Homeowners can do this themselves: Regularly remove and clean the nylon filter every 2 to 3 weeks (rinse with clean water and dry in a cool place, do not expose it to the sun to avoid deformation and embrittlement); clean the air outlet blades of the indoor unit with a dry cloth; check whether there is any accumulation of debris within 50 cm around the outdoor unit that hinders heat dissipation.
• Professional technicians must be entrusted according to regulations: Refrigerant pressure testing and leakage repair welding, high-pressure cleaning of indoor unit air drums and aluminum fins with liquid chemicals, reset of the drainage slope of hidden cold water pipes in the ceiling, and 220V dedicated power circuit configuration and leakage circuit breaker replacement.