Pilkington Activ™ Clear: Self-cleaning glass with photocatalytic coating

Saint-Gobain Pilkington has developed Activ™ Clear, a flat glass with self-cleaning function that is manufactured in the United Kingdom. The invisible coating works in two stages: photocatalysis breaks down organic dirt through natural daylight, then rainwater spreads evenly across the surface and rinses away dissolved contaminants. During longer dry periods, rinsing with tap water is sufficient. The technology reduces the need for manual cleaning, water, and chemical cleaning agents. The target customers are residential and commercial buildings, especially hard-to-access glazing such as roof windows, winter gardens, and glass facades.

How does the photocatalytic coating work?

The coating of Activ™ Clear combines two physicochemical mechanisms. In the first stage – the photocatalytic phase – the surface reacts with natural daylight and breaks down organic contaminants at the molecular level. This process runs continuously, even in cloudy conditions or at night. In the second stage, the hydrophilic property comes into play: instead of forming droplets, the coating attracts water, which spreads across the surface and removes dissolved dirt particles. This minimizes streaking, a known problem with conventional glazing.

The coating is applied using the pyrolytic online process – a permanent method established in flat glass production. The layer is vapor-deposited directly onto the ribbon at high temperatures during glass manufacturing and fuses with the glass surface. This guarantees a lifespan equivalent to that of the glass itself. The material achieves Class A according to EN 1096 for coated glass and meets the ASTM C 1376 standard.

Applications in residential and commercial construction

Pilkington recommends Activ™ Clear primarily for residential applications, but the product is also suitable for commercial projects. The specified areas of use include:

The advantage of continuous self-cleaning is particularly evident in roof windows and skylights, where dirt and leaves accumulate. When combined with insulating glass systems, Activ™ Clear can meet thermal requirements while reducing maintenance costs. The technology is also relevant for glass facades in urban environments where air pollution and organic deposits are a problem.

Processing and compatibility with further refinement

The glass is supplied in annealed form and can subsequently be thermally tempered, laminated, bent, or enameled without affecting performance or appearance. This flexibility allows integration into complex facade systems and laminated safety glass or tempered safety glass solutions for increased safety requirements. Pilkington provides processing guidelines as a separate document ("Pilkington Activ™ Handling and Processing Guidelines").

The coating is located on the exterior side of the glazing and is thus directly exposed to weather and UV radiation – a prerequisite for the photocatalytic effect. In multi-layer structures (e.g., insulating glass), the coated side must face outward. Planners should account for this in detail planning, particularly in complex facade designs with thermal protection glass.

Sustainability aspects and resource efficiency

Pilkington positions Activ™ Clear as a sustainable product. The self-cleaning function reduces the consumption of water and chemical cleaning agents. For large facades, this can mean significant savings over the service life – both ecologically and economically. The pyrolytic coating is free of organic solvents and is applied without subsequent chemical processes.

The company provides an EPD (Environmental Product Declaration) that quantifies the product's environmental footprint. For planners evaluating according to DGNB or LEED criteria, this documentation is relevant. The Declaration of Performance (DoP) is available on the Pilkington website; additional test reports can be requested by email.

Market environment and competitive comparison

Self-cleaning glass is not a new concept – several European and international manufacturers offer comparable solutions. Pilkington emphasizes British manufacturing and patented coating technology. The invisible coating is optically indistinguishable from uncoated glass, which is an advantage for prestigious facades. Compared to hydrophobic (water-repellent) coatings, Activ™ Clear relies on hydrophilicity – a different physical strategy that has proven particularly effective against organic contaminants.

Economic viability depends heavily on the application. For hard-to-access surfaces, the additional cost compared to standard glass pays for itself through savings in cleaning and scaffolding costs. For floor-to-ceiling windows in a single-family home, the economic advantage is less pronounced. Architects and building owners should therefore consider lifecycle costs, not just initial price.

Availability and technical support

Pilkington offers technical consulting, test reports, and samples through local distribution partners in the United Kingdom. The product line includes other Activ™ variants documented in a brochure ("Pilkington Activ™ Range Brochure"). A UK data sheet and sustainability document ("Pilkington Activ™ Actively Sustainable, Environmentally Green") are also available for specifications. Samples can be ordered via an online form.

The product has already been used in several European reference projects, including the Holmenkollen Metro Station in Oslo, a rooftop terrace building in Trondheim (Nordre Gate 12), the Odra Tower in Wrocław, and the Pyramide Berger in Traboch, Austria. These projects demonstrate the range from public infrastructure to residential high-rises to commercial special structures.

Conclusion: Niche solution with clear application profile

Pilkington Activ™ Clear offers a technically mature solution for low-maintenance glazing. The combination of photocatalytic dirt breakdown and hydrophilic water distribution works permanently and without external energy input. The greatest benefit lies in hard-to-access or large-scale applications where cleaning costs and risks are high. For architects who prioritize sustainability and lifecycle costs, the technology is a meaningful supplement to established insulating glass systems. Integration into existing planning processes is straightforward thanks to standards compliance (EN 1096, ASTM C 1376) and comprehensive technical documentation.