Glass Replacement

Broken, cracked, or failed glazing in a commercial shopfront is one of the most urgent repair requirements a business can face. A shattered pane leaves the premises physically open to the elements and to opportunistic theft. A misted or failed double-glazed unit, while less immediately critical, degrades the appearance of the frontage and compromises the thermal performance of the building envelope. In both cases, prompt replacement with correctly specified glass is essential.

Urban Shopfronts provides a comprehensive commercial glass replacement service across the UK, covering single-pane toughened glass, laminated security glass, sealed double-glazed units (DGUs), and specialist glazing including solar-control, acoustic, and security-rated products. We handle everything from a single broken panel in a shopfront to the complete re-glazing of a multi-unit retail parade.

Types of Commercial Glass

Understanding the different types of glass used in commercial shopfronts is important for specifying the correct replacement.

*Toughened safety glass* (also called tempered glass) is the standard glazing material for commercial shopfronts. Manufactured by heating float glass to approximately 620°C and then rapidly cooling it, toughened glass is four to five times stronger than annealed glass of the same thickness. When it does break, it fractures into small, relatively blunt granules rather than the large, sharp shards produced by annealed glass, significantly reducing the risk of laceration injury. Toughened glass is manufactured to BS EN 12150-1 and is permanently marked with the kite mark, the standard number, and the manufacturer's identification.

*Laminated glass* consists of two or more layers of glass bonded together with a polyvinyl butyral (PVB) or ethylene-vinyl acetate (EVA) interlayer. When broken, the fragments adhere to the interlayer rather than falling free, maintaining a degree of barrier integrity even after fracture. Laminated glass is manufactured to BS EN ISO 12543 and is specified where post-breakage performance is important — for example, overhead glazing, balustrades, and security applications where resistance to repeated impact or forced entry is required.

*Double-glazed units (DGUs)* — also called insulated glass units (IGUs) — consist of two panes of glass separated by a hermetically sealed cavity, typically filled with argon or krypton gas to improve thermal insulation. The cavity is maintained by a spacer bar around the perimeter, bonded to both panes with a primary butyl seal and a secondary structural sealant. DGUs are specified where thermal performance is a requirement — which, under Building Regulations Part L for non-domestic buildings, applies to virtually all new or replacement glazing in commercial premises. Centre-pane U-values for standard argon-filled DGUs typically fall between 1.0 and 1.4 W/m²K depending on the glass combination and coating specification.

*Security-rated glass* is laminated glass that has been independently tested and certified to resist attack. The principal standard for enhanced security glazing in the UK is PAS 24:2022, which tests the complete window or door assembly (not just the glass) against manual attack with common hand tools. For glazing-only performance, the relevant classification is BS EN 356, which grades glass from P1A (resistance to ball drop impact) through P8B (resistance to prolonged manual attack with an axe). Many commercial insurers now specify a minimum security glazing grade for ground-floor retail premises, and PAS 24 certification is increasingly required by landlords and local authority licensing conditions.

When Glass Replacement Is Needed

The most common reasons for commercial glass replacement are:

*Vandalism and impact damage* — a thrown object, a vehicle impact, or an attempted break-in can shatter or crack a shopfront pane. In the case of toughened glass, the entire pane will disintegrate; laminated glass may crack but typically remains in the frame. In both cases, replacement is required.

*Failed sealed units (misting DGUs)* — over time, the perimeter seal of a double-glazed unit can degrade, allowing moisture to enter the cavity. This produces a persistent misting or condensation between the panes that cannot be cleaned. A failed DGU no longer provides its designed thermal insulation performance, and its appearance is unacceptable for a retail frontage. The failed unit must be replaced; it cannot be economically repaired.

*Accidental damage* — a forklift manoeuvre, a delivery vehicle reversing into a glazed panel, or an internal impact from equipment or stock. We document accidental damage for insurance purposes in the same manner as vandalism damage.

*Regulatory upgrade* — in some cases, glass replacement is prompted not by damage but by a change in regulatory requirements or a landlord's specification. For example, upgrading from single-pane toughened glass to a DGU to meet Part L thermal requirements following a change of use, or upgrading to PAS 24 security glazing as a condition of a new insurance policy or licence.

Measurement and Specification Process

Accurate measurement and correct specification are critical to a successful glass replacement. Our process begins with a site visit where we measure the glazing aperture, record the frame rebate depth and bead detail, and identify the existing glass specification from the markings on the broken or failed unit. Where the existing specification cannot be determined from the remnants (for example, where the glass has been completely removed for safety), we consult the original shopfront installer's records or specify a replacement that meets the current regulatory requirements.

For DGU replacements, we record the overall unit thickness, the individual pane thicknesses, the spacer bar width and type, the gas fill requirement, and any low-emissivity or solar-control coating specification. We then order the replacement unit from our glazing supply network, which maintains stock of the most common standard sizes and can manufacture bespoke units to order within three to five working days.

Compliance and Standards

All replacement glazing is installed in accordance with BS 6262 (Glazing for buildings), which provides the code of practice for the design, installation, and maintenance of glazing in buildings. BS 6262 addresses glass selection based on location within the building, wind loading, human impact safety, and environmental factors.

For safety glazing — glass installed in critical locations where there is a risk of human impact — the relevant standard is BS EN 12600, which classifies glass by its breakage pattern and resistance to body impact. Critical locations are defined in BS 6262-4 and include glazing below 800 mm from floor level, glazing in or adjacent to doors, and glazing in areas where people might fall against the glass.

Toughened safety glass is manufactured to BS EN 12150, and laminated safety glass to BS EN ISO 12543. Both standards require permanent marking of the glass, and we verify the presence and correctness of these markings on all replacement units before installation.

For thermal performance, replacement DGUs must demonstrate compliance with Building Regulations Part L. We specify units with an appropriate combination of low-emissivity coatings and gas fill to achieve the required centre-pane U-value, and we provide documentary evidence of the U-value achieved for building control inspection where required.

Emergency Boarding Before Replacement

Where a glazing panel has been broken and the replacement glass is not immediately available, our first priority is to make the opening secure. We install temporary boarding — heavy-duty plywood or polycarbonate sheet secured within the existing frame — to protect the premises from weather ingress and unauthorised entry. The boarding is installed with discrete fixings that do not damage the frame, allowing clean removal when the replacement glass arrives.

For retail premises where maintaining visibility and trading appearance is important, we can install clear polycarbonate temporary glazing rather than opaque boarding, subject to the security risk assessment for the premises.

Turnaround Times

Standard toughened single-pane replacements in common thicknesses (6 mm, 8 mm, 10 mm, 12 mm) are typically available within 24–48 hours from our glazing supply network. Standard argon-filled DGU replacements are available within three to five working days. Specialist glass — security-rated laminated glass, solar-control glass, acoustic glass, or non-standard sizes — may require five to ten working days depending on the specification and manufacturer availability.

For emergency glazing requirements, we can often source standard toughened glass on a same-day or next-day basis, with installation scheduled immediately upon delivery.

Colour-Matched Frames

Where glass replacement requires the removal and refitting of glazing beads, cappings, or frame trim, we take care to match the existing frame colour and finish. For current-production aluminium profile systems, replacement beads and trims are available in the original colour from the system supplier. For older or discontinued profiles, we source the closest available match and, where necessary, arrange powder-coating to the original RAL or BS 4800 colour reference to ensure a seamless appearance after repair.