What are Alternative Solutions in the Building Code of Australia?

The  Building Code of Australia (BCA) is a ‘performance based’ document, with each section in the BCA setting minimum mandatory levels of compliance  – these are termed ‘Performance Requirements’.

So what are Performance Solutions, (also referred to as Alternative Solutions)? The National Construction Code (NCC), which includes the Building Code of Australia (BCA) (Volumes One and Two)  is a ‘performance-based’ building code.

Jigsaw Puzzle Pieces, with missing piece

The Australian Building Codes Board has been quoted as stating that the use of a performance-based approach to compliance  ‘provides practitioners with a strong degree of flexibility to determine the most appropriate means for demonstrating compliance with the relevant Performance Requirements’.  

This, therefore, allows some level of creativity in how compliance (or a compliant building solution) can be achieved and could see the introduction of new materials, technologies or methodologies, which could also see some efficiencies, better outcomes and cost savings, whilst still meeting the relevant Performance Requirement.

Methods of providing a compliant building solution are shown in the diagram below that has been adapted from the BCA.  There are three methods to achieve compliance with the Performance Requirements:

  1. complying with the ‘Deemed-to-Satisfy’ Provisions (or the prescriptive approach detailed within each part of the BCA);
  2. formulating a Performance (Alternative) Solution (i.e. adopting a ‘performance-based approach’); or
  3. a combination of both of the above.

Compliance with the ‘Deemed-to-Satisfy’ provisions is easier as these building solutions are all detailed within the pages of the BCA and will be deemed to comply with the relevant Performance Requirements.

If a performance-based approach is adopted to achieve compliance an ‘Alternative Solution’ must be developed for acceptance by the building surveyor/building certifier.

An ‘Alternative Solution’ has been defined as ‘a building solution which complies with the Performance Requirements other than by satisfying the  ‘Deemed-to-Satisfy’ provisions of the BCA.’

A simple example of an ‘Alternative Solution’ is automation of a hinged leaf door. This undoubtedly provides a better building solution and provides a greater level of accessibility for users of a building (including those with mobility limitations including reduced hand dexterity, those using a mobility aid such as a wheelchair or a walking frame, amputees etc.). This design solution does not ‘fit’ in with the ‘Deemed-to-Satisfy’ provisions and is not an option provided in AS1428.1. Therefore, it is an ‘Alternative Solution’ that must be developed and documented.

Any proposed ‘Alternative Solution’ must be documented, and verified it complies with the relevant Performance Requirements. The BCA details ‘Assessment Methods‘ that can be used to confirm compliance, however, to ensure compliance with the Access to Premises Standards the use of Expert Judgement alone should be avoided for access-related issues.