Following the Greenfell tragedy in London and earlier Lacrosse fire in Melbourne, regulators across Australia have scrambled to address issues relating to flammable cladding.
Whilst much of the attention involves products which fail to meet National Construction Code (NCC) requirements, efforts have also been afoot to improve the Code itself.
Toward this end, the Australian Building Codes Board (ABCB) has prepared an out-of-cycle amendment to the Code. Set to commence on March 12, NCC 2016 Volume One Amendment 1 is part of a set of measures designed to help address fire safety issues agreed to between the Building Ministers Forum and the ABCB. A preview of the changes has been released.
The amendment will be accompanied by new guidance material. This includes a new Evidence of Suitability Handbook 2018 and a revised Advisory Note 2016-3 ‘Fire Performance of External Walls and Cladding’. Information seminars will be conducted throughout 2018.
ABCB general manager Neil Savery says the changes provide greater clarity about the Code’s requirements and its intent.
“At its simplest, the changes mean that practitioners will need to familiarise themselves with the changes and undertake their work accordingly,” Savery said.
“The changes do not alter the performance requirements of the NCC, but help improve clarity and intent, particularly around the deemed to satisfy and evidence of suitability provisions.”
The amendment deals with four areas:
- Introduction of a new verification method for testing of external wall assemblies for fire propagation
- Revision of evidence of suitability provisions
- Clarification of various fire safety provisions
- Greater stringency for sprinkler protection of balconies.
New verification method CV3
First, there is the new verification method, which is known as CV3. This deals with external wall systems and provides a means by which large-scale testing can be used to verify that an external wall assembly does not contribute to the spread of fire in a Type A or Type B building.
Specifically, it determines that compliance with the performance requirements contained in CP2 of Volume One that the building have elements which avoid the spread of fire can be verified as far as external wall systems are concerned when several criteria are met.
- That compliance with CP2(a)(iii) to avoid the spread of fire between buildings has been met in accordance with CV1 and CV2 as appropriate
- The external wall system has been tested for external wall performance in accordance with AS 5113, has achieved EW classification and incorporate cavity barriers which have been included in the tests at the perimeter of each floor where cavities are present
- In the case of Type A construction, the building be protected throughout by a sprinkler system which complies with Specification E1.5 and has:
o Sprinkler protection to balconies, patios and terraces, and where overhead sprinkler coverage is not achieved alongside the external wall, sidewall sprinkler heads are provided at the external wall for the extent of the balcony, patio or terrace where overhead sprinkler coverage is not achieved; and
o the sprinkler system is capable of providing sufficient flow to serve the design area (assumed area of operation) required by AS21 18.1 for the relevant hazard class on each floor level plus the design area (assumed area of operation) required by AS2118.1 for the floor level above, except with the former level is the floor level below the uppermost roof or any floor level which is wholly below ground.
- In the case of Type B construction, the building is either:
o a Class 5,67 or 8 building or Class 4 part of a building; or
o a Class 2, 3 or 9 building that is protected throughout by a sprinkler system that complies with Specification E1.5 or has any opening in external walls separated by a slab or other horizontal construction which complies with C2.6(a)(iv) as if the building were of Type A construction.
Evidence of suitability
Provisions relating to evidence of suitability requirements have been revised.
A significant change is the insertion of a new requirement in A2.2(b) which requires the form of evidence to be appropriate to the use of the material, product, form of construction and design to which it relates. This is important as the previous requirements surrounding forms of evidence were considered by some to be overly loose. Now, the form of evidence must be appropriate and room for a laissez faire approach has been removed.
Other changes include clarifying the language of A2.2 and strengthening the wording of current options.
Clarification of provisions
Clarification has been provided in respect of a range of provisions.
This includes those which relate to external wall claddings and attachments, that provide exemptions to non-combustibility requirements and that control the fire hazard properties of building elements.
Greater stringency for sprinkler protection of balconies
Improved stringency has been added in regard to the sprinkler protection of balconies though the referencing of an updated sprinkler standard, AS218.1-2017 ‘ Automatic fire sprinkler systems – General systems’.
The 2017 edition of this standard replaced the 1999 version and is referenced at Specification A1.3 Table 1.
According to Savery, the amendment will not significantly alter what practitioners need to do on the ground. However, he says the changes will help them to better understand how to apply the Code in respect to external wall claddings and assemblies as well as product selection.
Those most impacted, he says, are practitioners who have not applied current provisions of the Code as intended.
Take, for instance, C1.12(f) of NCC 2016 and earlier editions. This enables the use of bonded laminated materials where non-combustible materials are required provided that each laminate is non-combustible, each adhesive layer does not exceed one millimetre in thickness, the total thickness of adhesive layers is no more than two millimetres and the Spread of Flame Index and the Smoke-Developed Index of the laminate material as a whole does not exceed 0 and three respectively. Regulations, Savery says, never intended to permit the use of bonded laminated materials with a combustible core where non-combustible materials are required. However, numerous practitioners had considered that a core is not a lamina and therefore could be combustible.
The correlating provision under the amendment, he says, clarifies that the core is a lamina which like any other lamina must be non-combustible for the concession to be allowed.
In another example, specific and measurable criteria have been provided to assess when combustible elements can be attached to certain walls. For example, C1.14(h) of NCC 2016 Volume One Amendment 1 sets out measurable requirements for a combustible sign, whereas the current relevant provisions for combustible signs are more qualitative.
According to Savery, the amendments cannot on their own address broader issues associated with flammable cladding and non-conforming building products. Other initiatives, he said, are needed in conjunction with these.
Nevertheless, he says the amendments will help by assisting practitioners to understand their obligations and the intent of the regulatory requirements. Moreover, if the revised evidence of suitability requirements are applied correctly, he says that will help reduce the incidence of non-conforming products.
- What has changed: NCC 2016 Volume One Amendment 1A1.1 A new defined term, ‘Accredited Testing Laboratory’ has been inserted to replace ‘Registered Testing Authority’. Consequently, where ‘Registered Testing Authority’ is used throughout the NCC, it is replaced with Accredited Testing Laboratory’
- A1.1 A newly defined term, ‘Ancillary Element’ has been inserted
- A1.1 A newly defined term, ‘Appropriately qualified person’, has been inserted
- A1.1 A new defined term, ‘Certification body’, has been inserted
- A1.1 A new defined tern, ‘Product Technical Statement’, has been inserted
- A1.1 The defined term, ‘Registered Testing Authority’, has been replaced with ‘Accredited Testing Laboratory’
- A2.1 The title has been amended, sub-clause (a) has been amended and a new sub-clause (b) has been inserted to clarify how suitability is achieved and documented
- A2.2 The provision has been amended to clarify the various forms of documentary evidence used to demonstrate sustainability. A new subclause (b) has been inserted requiring that the form of evidence used must be appropriate.
- Specification A1.3 Table 1 The 2017 edition of AS2118 Part 1 ‘Automatic fire sprinkler systems – General systems’ incorporating Amdt 1 has been referenced. The 1999 edition has been retained in part for a 12 month transitional period
- CV3 A new verification method has been inserted to verify compliance with Performance Requirement CP2 with regard to fire spread via the external wall. CV3 is a means for verifying by large-scale test than an external wall assembly does not contribute to spread of fire in Type A or Type B building
- C1.1 The provision has been amended to improve readability and clarify the application of Specification C1.1
- C1.9 A new provision has been included to combine a series of requirements and concessions for non-combustible internal building elements
- C1.10 The provision has been amended to clarify that the requirements apply to internal building elements
- C1.12 The provision has been deleted on account of its content being re-located to C1.9
- C1.14 A new provision has been included to clarify what ancillary elements be applied to an external wall that is required to be non-combustible
- Specification C1.1 Clause 2.4 The clause has been amended to clarify that the method of attaching an item to a building element much not compromise the required FRL for the element
- Specification E1.5 Consequential amendments have been included on account of referencing the 2017 edition of AS2118.1
- NSW C1.10(a) The variation has been amended to maintain consistency with national standards
- SA C1.1(a) The variation has been amended to maintain consistency with the national provisions.