The National Construction Code Volume One, Building Code of Australia 2019 (NCC), allows the use of timber construction systems under the Deemed-to-Satisfy (DTS) Provisions for all buildings up to 25 metres in effective height, ‘mid-rise construction’.
The DTS provisions cover both traditional ‘lightweight timber framing’ and ‘massive timber’ products such as Cross-laminated Timber (CLT) and Laminated Veneer Lumber (LVL) in conjunction with the use of appropriate non-combustible fire-protective coverings – termed ‘fire-protected timber’ in the NCC – and appropriate compliant automatic sprinkler systems. With mid-rise timber construction design, fire and sound are two of the major considerations: appropriate fire-resisting construction is critical to providing acceptable levels of fire safety, while sound or acoustic performance is essential because of its daily impact on occupant amenity and quality of life.
This Guide applies to Class 5 to 8 and 9b Commercial Buildings or parts of buildings and Class 4 parts. It aims to assist in providing specific advice on fire safety and, to a limited degree for the majority of these building types, acoustic performance and is specifically written for use by designers, specifiers, builders, regulatory and certifying authorities. It is set-out according to a simple step- by-step process as presented in Figure 0.2. The steps are then used as the basis for headings throughout the main body of this Guide. Details on the scope and other important aspects of the Guide are set out below.
Mid-rise Timber Buildings Commercial and Education Class 5, 6, 7, 8 and 9b (including Class 4 parts)
This Guide explains how to achieve the targeted fire and sound Performance Requirements in the National Construction Code (NCC) for the following mid-rise timber buildings using the Deemed-to- Satisfy pathway for fire-protected timber first introduced in the 2016 edition of the NCC, with further developments included in the 2019 edition:
• Class 5 – Office Buildings
• Class 6 – Shops, Restaurants, Bars etc.
• Class 7 – Carparks and Storage / Wholesale Facilities
• Class 8 – Laboratory, Manufacturing / Processing Goods or Produce
• Class 9b – Assembly Buildings including Education Facilities
The treatment of a Class 4 part of a building (a dwelling in a Class 5, 6, 7, 8 or 9 building) is also addressed in this Guide.