NEW BARRIER REQUIREMENTS AS 1288: 2021

NEW BARRIER REQUIREMENTS AS 1288: 2021

By Russell Harris & Dr Pouya Abtahi

INTRODUCTION

The National Construction Code 2022 (NCC 2022) was released by the Australian Building Codes Board (ABCB) on 1 October 2022 and is now available for use, subject to various transition arrangements imposed by the ABCB as well as individual states and territories. Generally speaking, except for the livable housing, condensation and energy provisions, the NCC will become mandatory in most jurisdictions from the 1 May 2023. Queensland, Victoria, New South Wales and Tasmania will adopt NCC 2022 on 1 May 2023, and Western Australia will adopt on 1 May 2024. South Australia, Australian Capital Territory and Northern Territory have made no formal announcement yet as to an adoption date. Transition periods for other parts of the NCC, such as energy efficiency, condensation mitigation, and livable housing provisions, will come into effect on 1 October 2023. Until the adoption date in each jurisdiction, NCC 2019 Amendment 1 remains in force and can be used and referenced.

The latest edition of the NCC references several Australian Standards which have also been revised or updated, including AS 1288 which was revised in 2021 to include, among other things, updates to balustrades and barriers in Section 7.

SUMMARY OF KEY CHANGES

The aim of the 2021 revision of AS 1288 was primarily to clarify existing requirements and reduce the likelihood of misinterpretation of the barrier provisions within the Standard. Additionally, the 2021 revision introduced a number of changes and new requirements designed to:

- Limit the use of monolithic toughened glass in barriers/balustrades above 5 m from ground level

Glass barriers used to protect a height of more than 5 m are now required to use laminated glass (including annealed laminated, heat-strengthened laminated or toughened laminate). Monolithic toughened glass can no longer be used in these locations.

- Resolve ambiguity and clarify requirements for support conditions and interlinking handrails in structural glass barriers/balustrades

The prescriptive solutions provided inSection 7 have been extensively revised.This includes a revision of the definitionand application of ‘interlinking handrails’ toprovide greater clarity and, specifically, tomake it clear that all structural balustrades protecting a height of more than 1 m,including systems utilising spigots, standoffsand other point-fixed type mountingsystems, must be designed in accordancewith Section 3 General Design Criteria.

- Introduce new test methods for glass balustrades, particularly for spigot supports and stand offs (point-fixed glazing)

Alternatively, a new test methodology is introduced in Appendix H, which can be used in lieu of an engineered solution (in accordance with Section 3 outlined above) and allows performance verification of balustrade systems not covered by the DTS provisions. This new test method provides uniform, predictable and repeatable procedures for balustrade testing applicable for balustrades in all building classes.

- Clarify loading requirements for glass balustrades in various building classes and applications

Appendix J now includes specific loadcriteria from AS/NZS 1170.1, relevantto various use types across all buildingclasses in the NCC. This makes it easier todetermine the specific load combinationsrelevant to any given application,without the need to purchase additionalStandards. It helps the user to select therelevant applied loads when using the DTStables in Section 7 of AS 1288.

- Quantify acceptable post-breakage deflection of structural laminate glazing and include a new informative test methodology for design verification

Structural glass barriers/balustrades protecting a fall of more than 1 m must be designed in accordance with serviceability limit states and maximum deflection limits outlined in clause 3.3.3. Maximum deflection under a 200 Newton force, applied post-breakage, is limited to 250 mm. Appendix I introduces a new informative post-breakage test for structural glass balustrades.

WHAT DOES THIS MEAN FOR ME?

First and foremost, we recommend that you purchase your copy of AS 1288: 2021 as soon as possible and familiarise yourself with the new requirements to assess how these reforms may affect your business. While AS 1288: 2021 may be used immediately, it will become mandatory from 1 May 2023, depending on your state or territory.

Additionally, we emphasise that the use of monolithic toughened glass in locations 5 m or more above the surface below is no longer permitted. This will generally apply for all Development Applications approved on or after the 1 May 2023 or, in the case of complying or exempt development, work commenced after this date.

Most importantly, barrier systems which use spigots, face-mounted stand-offs or other point-fixed systems or other structural balustrades protecting a height of more than 1 m, must be designed in accordance with Section 3, which generally requires engineering certification or testing in accordance with Appendix H.

To ensure barrier/balustrade installations are compliant, we recommend that you purchase hardware from suppliers who have had their product tested (as a whole assembly) or engineered for a particular load application and make your glass selection in accordance with their specifications. The required certification needs to show the compliance of the system for an occupancy type, with the related load requirements clearly outlined to the client upon purchase.

Fig 1: Channel glazed cantilever balustrade with interlinking handrail

Fig 2: Spigot fixed balustrade with interlinking handrail

NOTE: Requires engineered or tested system

DID YOU KNOW…

Compliance and ensuring a level playing field is one of the core priorities of AGWA and we will continue to work on this important agenda. We routinely investigate and report instances on non-conformance to building authorities across Australia and undertake on-site inspections, with some instances proceeding to legal action with AGWA being called upon as an expert witness.

In one recent example, AGWA was informed by one of our members of a potential noncompliant barrier installation in a new multilevel residential development. The member advised they had unsuccessfully tendered for the job using a cantilevered structural laminate system as the owners had indicated a preference for uninterrupted views of the impressive outlook from the property. They were later shocked to learn that the job had gone ahead with what they suspected to be a non-compliant balustrade system and presented us with a photo from the building during its construction showing a balustrade fixed to the balcony's concrete slab using a spigot support system without any handrail.

When contacted by AGWA the builder claimed that a qualified structural engineer had designed the barrier system and that a handrail would be part of the design, but several months later, despite the project being complete and the apartments largely occupied, the barrier was still without a handrail.

Consequently, AGWA informed the builder that unless a handrail was fitted in accordance with the balustrade design, it was unlikely to meet the applied load, meaning the installation was non-compliant and posing a potentially serious safety risk to the building occupants.

Being committed to ensuring a safe and compliant outcome was achieved, and in the interest of a level playing-field, AGWA continued to engage with the builder to seek confirmation that the handrail was fitted as per the required standards. Whilst it is not appropriate to go into details of this correspondence, suffice to say that after almost 6 months of follow-up and discussion, we have recently confirmed that the handrail has now been installed.

Fig 3: Face mounted (stand-off) balustrade with no handrail

NOTE: Requires engineered or tested system