Glass balustrades have surged in popularity in New Zealand, especially in high value projects because they offer the advantages of clear views, excellent wind protection, and enhanced light penetration. Thanks to innovative digital print options and frit patterns that withstand even the harshest weather, these balustrades are now more versatile and vibrant than ever.

For a safe and compliant installation, it is crucial to consider both glass and hardware together. Metro offer a free online PS1 service for all standard balustrades. However, a common issue arises when support structures and substrates are not built in accordance with the issued PS1 compliance documentation, leading to unsafe systems and costly rectifications. It is best if you can ensure your builders review the PS1 early in the project to ensure substrates and fixings are understood and correctly implemented, facilitating a straightforward installation process.

Glass balustrades must either comply with NZBC Acceptable Solutions B1/AS1, B2/AS1, F2/AS1, F4/AS1 and Verification Method B1/VM1  or Alternative Solutions.

The NZS 4223 set of standards which is used for glass selection, is sponsored by MBIE and are available for free download:
Download NZS 4223 Standards here  

As well as the free online PS1s for standard balustrade designs, Metro Glass provide an in-house process for specific designs and PS1s, with a nominal fee agreed upon during the plan assessment.

To ensure safety, especially for barriers protecting from falling, consider these critical points:

• Structural toughened safety glass barriers: Require an interlinking rail for falls of 1 metre or more.
• Structural heat strengthened or toughened laminated safety glass barriers: Do not necessarily require an interlinking rail but must be tested to meet NZBC "post-failure" load support requirements (20kg, 1 min < 250mm deflection).
• High traffic/public areas: Should Include edge protection on all toughened glass (including laminated toughened glass) to minimise edge impact and potential breakage.

Here's a look at how different glass types perform:

Toughened safety glass is hard to break, but when it does it shatters into thousands of small pieces meaning injury from lacerations is reduced. However, this poses a risk for falls if the barrier was intended to protect a height of 1m or more.

When Laminated safety glass breaks, it is held together by the interlayer. Metro Glass carries out in-house testing to ensure the specific glass make up in the PS1 document complies with required post-failure loads to match the hardware.

Toughened laminated safety glass (LSG) with a stiff interlayer is designed to remain upright even when it has broken. The stiffened interlayer ensures that it can hold post-failure loads and this type of glass can be used with no interlinking rail for clearest views.

To guarantee a smooth-running project, always ensure your builder or customer has viewed the PS1 before starting if a glass balustrade is being installed on-site. If you have any questions about a PS1 issued by Metro Glass, contact us at [email protected], or if you need a quote on a glass balustrade contact [email protected].

Enhance your building projects with the elegance and functionality of glass balustrades, ensuring compliance and safety with Metro Glass’s expert support.