When glazing issues appear in a commercial building, the instinctive response is often to call a window cleaner. Water ingress, misted units, staining around frames or draughts are treated as cosmetic problems rather than symptoms of deeper failure. In many cases, well-meaning cleaning contractors are asked to ‘have a look’, reseal edges, or simply clean more aggressively in the hope that the problem will go away.
It rarely does.
Unfortunately, relying on window cleaners to address commercial glazing defects can actually accelerate deterioration and significantly increase long-term repair costs. The same applies to one of the most common cleaning habits we see across commercial estates: the use of Fairy washing-up liquid on windows and frames!
Most glazing failures don’t start with glass. They start with seals, gaskets, fixings and interfaces. Cleaning alone won’t identify that, and in some cases, it actively makes it worse.
Glazing Cleaning Is Not a Glazing Inspection
Window cleaners play an important role in maintaining appearance and visibility, but their remit ends there.
They are not trained to assess glazing systems as part of a building envelope, nor are they equipped to diagnose failure mechanisms within sealed units, pressure plates, gaskets, setting blocks or drainage paths.
When a window cleaner is asked to address a glazing issue, the intervention is almost always superficial. Silicone is applied to visible joints, staining is scrubbed away, or pressure washing is used to clear debris. These actions may temporarily improve how the window looks, but they do nothing to address the root cause of water ingress, air leakage or thermal failure.
Worse still, they can mask early indicators that a specialist glazing inspection would identify immediately. Moisture tracking within frames, micro-movement of units, compression failure of gaskets or blocked drainage channels are often concealed once surfaces are cleaned or resealed without understanding the system design.
In commercial environments such as hotels, offices, healthcare buildings, and educational establishments, this creates a false sense of resolution while the underlying defect continues to progress.
Washing-up Liquid as a Cleaning Agent: The Hidden Damage Caused by Fairy Liquid
One of the most common practices we encounter during glazing inspections is the routine use of washing-up liquid as a cleaning agent.
It is widely assumed to be mild, safe and effective. In reality, it is entirely unsuitable for glazing systems.
Fairy (and most other brands of washing up) Liquid contains petroleum-based surfactants. These are effective at cutting grease, but the compounds are aggressive to many of the materials used in commercial glazing assemblies. Over time, repeated exposure causes seals and gaskets to degrade, lose elasticity and shrink. Once this happens, the glazing system can no longer accommodate movement, maintain compression, or form a continuous weather-tight barrier.
The result is gradual but inevitable failure. Water ingress appears intermittently at first, often only during wind-driven rain. Draughts develop as air paths open around frames. Condensation increases as thermal performance drops. Eventually, sealed units fail completely.
From a defect identification perspective, this type of chemical degradation is particularly problematic because it is rarely attributed to cleaning practices. Instead, responsibility is often misassigned to age, weather exposure or poor installation, when in fact the damage has been chemically induced over years of incorrect maintenance.
Why Defects Require Specialist Glazing Investigation
Commercial glazing systems are complex assemblies that form a critical part of the building envelope. They must accommodate structural movement, thermal expansion, wind load, drainage and vapour control simultaneously. When something fails, the cause is rarely isolated to a single visible point.
Practical glazing inspections require close access, controlled testing and an understanding of how the system was designed to perform as a whole. This includes assessing gasket condition and compression, identifying failed seals, reviewing drainage paths, checking fixing integrity and understanding how interfaces with surrounding façade elements behave under load.
This level of defect identification cannot be achieved from ground level or during routine cleaning. It requires trained specialists who understand glazing behaviour and can distinguish between cosmetic symptoms and systemic failure.
The Cost of Getting It Wrong
Treating glazing defects as cleaning issues is not just a technical mistake; it is a financial one. Temporary fixes and repeated cleaning visits consume maintenance budgets without reducing risk. Meanwhile, undiagnosed defects continue to allow moisture ingress, damaging internal finishes, disrupting occupants and increasing long-term liability.
In commercial settings, the consequences extend beyond repair costs. Hotel rooms taken out of service, office productivity impacted by draughts and leaks, reputational damage from visible deterioration, and compliance risks where building performance standards are not met all stem from the same root problem: the absence of proper defect identification.
When glazing systems fail, replacement is rarely cheap. But in many cases, targeted commercial glazing repairs informed by accurate inspection can extend system life significantly and prevent wholesale replacement.
Specialist Glazing Inspections: Getting the Right Expertise Involved
The solution isn’t to simply stop cleaning windows; it is to understand its limits.
Cleaning should be part of a broader, informed maintenance strategy that includes periodic specialist glazing inspection. Cleaning agents should be compatible with glazing materials, and any signs of failure should trigger investigation rather than surface treatment.
At Building Transformation, our glazing inspection work focuses on understanding how and why systems are failing, not simply what they look like. By combining specialist access capability with detailed defect identification processes, we are able to provide actionable insight that informs long-term maintenance and repair decisions.
Commercial glazing services should be based on evidence, not assumptions. If a window is leaking, misting, staining or deteriorating, the answer is not more cleaning or another bead of silicone. It is a proper investigation that identifies the defect at the source and addresses it appropriately.
Because when it comes to glazing, what you can’t see is usually what matters most, and cleaning alone will never reveal it.
