Design and Green Star environmental rating

GBCA Life Cycle Impacts Credit


Under the Green Building Council of Australia’s (GBCA) Green Star rating system, there is a credit that can be obtained for the efficiency of steel use called the Life Cycle Impacts Credit.

This credit relates to the engineering design of the project and up to one point is available when there is a reduction in the mass of steel framing used when compared to standard practice. The reduced mass can be demonstrated either by:

  • the use of high-tensile grade steel material, or
  • the reduction in mass of steel framing by 5% when compared to a suitable reference building.

The Life Cycle Impacts point for the use of high-strength steel can be awarded if the project team can demonstrate that:

  •  ≥ 95% 'Category A' product, and
  • ≥ 25% 'Category B' product meet the strength grades in the table following, as applicable
Category A:  ≥ 95% by weight Minimum strength Grade MPa
Roof and wall sheeting 550
Profiled steel decking 550
Purlins and girts 450
Light steel framing 450

 

Category B: ≥ 25% by weight Minimum strength Grade MPa
Hot rolled structurals 350
Hot rolled plate 350
Cold-formed and hollow sections 450
Welded sections 400


The Life Cycle Impacts point for reduction in mass can be awarded if the project team can demonstrate that the project results in a 5% or more reduction in mass of steel framing when compared to a suitable reference case building.

To demonstrate compliance a qualified structural engineer must submit the following:

  • A description of how the amount of steel has been reduced
  • Justification of a reference case
  • Calculations of the reduction in the total amount (by mass) of steel necessary for the design structure against the reference case, and
  • Confirmation that the reduction has been achieved without changing the load path to other structure elements that are not steel.

Resources


GBCA Green Star – Design & As Built