Quensus warns that vacant and partially occupied buildings face heightened water damage risks as winter approaches, putting developers, property owners and insurers under pressure to prevent burst pipes and undetected leaks from escalating into costly claims. The leak prevention specialist highlights how intelligent water monitoring and automatic shut-off technology can help limit losses when buildings are left unattended.
Quensus’ analysis highlights the scale of the problem, with escape of water accounting for approximately 30% of UK property claim costs, according to industry actuarial analysis cited by the company. It also points to construction industry data suggesting around two-thirds of sites experience water escape incidents. In one documented vacant new-build handover case, flooding resulted in a £2.5m loss, while a separate incident delayed a programme by 18 months.
These incidents expose a particular weakness in the period between construction completion and full occupation. Buildings may contain expensive finishes, newly commissioned mechanical and electrical systems and substantial investment, yet have little operational history and no permanent occupants to identify problems early. Without someone on site, a leak can continue for hours before it is discovered, spreading through floors and damaging completed interiors.
Cold weather adds to the exposure. Water trapped in unheated areas, plant rooms and service voids can freeze, damaging pipes and fittings before leaks emerge during a thaw. Temperature fluctuations can also place stress on joints and flexible connections. Meanwhile, temporary heating arrangements, incorrectly configured frost protection and commissioning errors can leave vulnerable sections of a building exposed.
For developers and investors, the consequences extend beyond the immediate repair bill. Flooding can delay handovers, disrupt sales and rental schedules and require completed apartments or commercial spaces to be stripped back for remedial work. Contractors may face disputes over defects and retention payments, while insurers and brokers can respond to repeated losses with greater scrutiny of vacant-building safeguards, excesses and policy conditions.
Quensus describes the period between practical completion and stable occupation as the “Handover Vulnerability Gap”, when financial exposure is high but building systems have yet to establish a reliable operating history. Winter can intensify this vulnerability, particularly across developments undergoing phased handovers or waiting for tenants.
Conventional leak detection often depends on someone noticing visible damage or an unusual sound. That approach is less effective when properties are empty. Fixed flow thresholds can also generate unnecessary alerts when water use changes between construction, handover and occupation, or when systems periodically operate for frost protection.
Quensus’ LeakNet system uses learning-mode analytics to establish a baseline for normal water consumption at different stages of a building’s lifecycle. By comparing current flow against that profile, the system can identify unusual activity that may indicate a burst pipe or concealed leak. When a deviation is detected, alerts can be delivered through SMS and email, with remote monitoring available through the company’s FlowReporter dashboard. Automatic isolation at the water meter can also be used where policy and system configuration permit.
The objective is to reduce the time between a leak starting and the water supply being stopped. Limiting the volume of water entering a building can help prevent a local fault from becoming a wider property loss, particularly when an immediate physical response is not possible.
Quensus recommends that developers, facilities managers and contractors install monitoring before buildings enter their first vacant period. Systems should be tested before handover, including alert routing, shut-off functionality and arrangements for out-of-hours attendance. Teams should also establish procedures for periods when connectivity is lost and keep monitoring active throughout phased occupation.
Documented winter protocols can provide insurers and funders with clearer evidence of how risks are being managed. The approach also supports insurer-led water damage prevention initiatives, including Quensus’ work with Aviva Risk Management Solutions.
Quensus’ analysis highlights the importance of moving from reactive leak detection to proactive prevention, particularly when buildings are unoccupied and damage can go unnoticed. By combining intelligent flow monitoring with automatic water isolation, developers, property owners and insurers can identify abnormal water use earlier and reduce the risk of a minor leak becoming a major financial loss.
Read the full Quensus analysis
Copyright © 2026 FinTech Global
