Glass Risk Assessment

Glazing is a critical component of modern building envelopes, combining aesthetic appeal with structural performance. However, it also presents unique safety and operational challenges that go beyond standard design considerations. A glass risk assessment evaluates potential failure scenarios, residual hazards, and the implications for building safety, liability, and long-term asset management.

We spoke with our glass engineering expert, Richard Cave, to provide insight into the objectives, methodology, and practical benefits of conducting a glass risk assessment at various stages of a building’s lifecycle.

What are the primary objectives of a façade glass risk assessment, and how do they align with current building safety regulations?

A glass risk assessment looks beyond the standard considerations of glazing design, such as wind loads, occupancy loads, thermal stress, and impact classifications – to evaluate the potential consequences of glass breakage. This includes scenarios like broken glazing falling from height or people falling through glazing.

While BS 6262-1:2017 provides guidance on these risks, there is no explicit requirement under The Building Regulations 2010 for such assessments. However, health and safety considerations are embedded in The Construction (Design and Management) Regulations 2015, specifically for Designers (Clause 9) and Principal Designers (Clause 11), making, in our view, risk assessments a critical part of design.

How does a risk assessment differ from a standard façade condition survey?

A façade condition survey primarily evaluates the physical state of the glazing, looking for issues like delamination or fractures. A glass risk assessment, however, considers residual risks that may not be immediately visible. For example, monolithic toughened glass may appear serviceable with no observable defects but still carries inherent risks if it fractures due to its breakage characteristics.

What are the key benefits for building owners in commissioning a glass risk assessment, particularly regarding long-term asset management and liability?

A glass risk assessment can identify previously unknown risks in a building envelope. Addressing these risks -whether through operational procedures, remedial works, or replacement -reduces the likelihood of incidents and limits potential liability. There are notable cases worldwide where unassessed glazing risks have resulted in near-misses, injuries, and fatalities, highlighting the importance of proactive assessment.

At what stage in a building’s lifecycle should a glass risk assessment be carried out: design, construction, or occupancy?

Ideally, during the design stage. Early assessment allows us to configure glazing in the safest way from the outset, avoiding costly and disruptive changes during construction or after completion. The goal is to achieve a risk level as low as reasonably practicable (ALARP), and it’s far more effective to install the safest glazing initially rather than retrofitting later.

Are there specific types of buildings or façade systems where glass risk assessments are especially critical?

All buildings deserve careful consideration, but high-footfall city-centre buildings naturally carry greater risk. Certain façade systems also require extra attention. For instance, structurally sealant glazed systems rely solely on sealant adhesion; failure of the internal panel can compromise the external pane. Spandrels are also complex due to restrictions under Regulation 7 of The Building Regulations for certain buildings, which limits laminated glass options, meaning alternative solutions or higher-risk glass types may be required.

How do you determine the appropriate methodology or level of detail for a risk assessment based on a building’s use, location, or age?

Our approach is qualitative, based on a risk matrix rather than statistical models, which often lack sufficient data for confident conclusions. Building use, location, and age influence risk consideration. We rely on building management input to assess factors like occupied areas and expected footfall. Age is particularly relevant regarding Nickel Sulphide (NiS) inclusions, which tend to pose less risk over time but remain a consideration throughout the glazing’s service life.

Should existing glass risk assessments be updated periodically to capture contemporary industry thinking?

Glass technology has remained relatively stable over recent decades, with laminated glass consistently among the safest options. Regular updates are not usually necessary unless the building owner’s risk appetite changes or glazing replacement is planned. Replacement projects are an ideal opportunity to reassess configurations and ensure they meet current safety expectations.

Summary

A comprehensive glass risk assessment is an essential component of responsible façade design and long-term asset management. By identifying potential hazards early, whether during design, construction, or refurbishment – building owners can reduce risks, protect occupants, and limit liability.

Engaging experienced professionals to carry out these assessments ensures that all relevant factors, from glazing type to building use and location, are thoroughly considered. As Richard Cave emphasizes, the safest approach is to integrate risk management into the design from the outset, ensuring that the façade not only meets aesthetic and functional objectives but also prioritizes safety.

For building owners, designers, and facility managers, commissioning a glass risk assessment is not just a regulatory consideration, it is a proactive step toward creating safer, more resilient buildings.