Under the ‘Details’ tab of your Design, there is an entry field for ‘Design Purpose’. This field helps the software identify the different purposes of each design in your project. This is especially important for design improvement purposes.
Ensuring this field is defined accurately also helps define your project’s progress towards a lower impact outcome. It is also used to populate the GHG Performance Chart for your organisation or personal dashboards which is calculated from the difference between your BAU designs vs Final/Proposed designs. The chart is to help promote friendly competition among organisation members and the wider eTool community. It is also to remind users of the ultimate goal of using LCA – to implement improvement strategies to reduce overall GHG impacts.
Under the ‘Design Purpose’ drop down menu, there are a number of selections to choose from. The meanings for each option are explained in the list below. Note that some Design Purposes are restricted to one per structure, if you are unable to select a purpose this is the likely reason (you will need to change the purpose of the other design, see below for details of each purpose and which ones are unique to structures).
LCA Purpose
‘LCA’ options are for projects that have progressed further along the design development stage. Usually the general geometry of the project has been defined or a cost plan is available for budgeting purposes. There will also be early stage drawings and plans available. The intention for a ‘design review’ stage LCA study is to provide more detailed LCA guidance to more accurately identify hot-spots which will help refine the specification decisions for the project as it proceeds towards the final version of the design.
Under this category, there are the following options:
- Business As Usual: for the ‘business-as-usual’ base/reference design of the project
- Scenario: other option/scenario designs that explore different improvement strategies that may or may not be considered for the ‘Final’ design.
- Proposed**: the ‘Proposed’ version of the design that is a compilation of chosen improvement strategies/scenarios that have already been identified and implemented by the project/design team. When the LCA is conducted in-house by eTool assessors, this design is usually the client’s proposed version.
- Improved: this design is the further ‘Improved’ version of the Proposed design. Contains additional improvement strategies/scenarios to demonstrate the top limit of what is achievable in terms of environmental performance. When conducted in-house by eTool assessors, this design is the improved version of the client’s proposed design.
- Final**: The ‘Final’ design that feature the improvement strategies/scenarios that have been confirmed by the developers/builders to implement for the project after reviewing the Improved Design. Typically the ‘proposed’ design at Stage 4 or As Built stage of a project. The GWP savings recorded in this design (compared to the Stage 2/Design stage Proposed Design) will also go towards the eTool Community GWP savings leader board as well should you choose to participate in that.
- As-Built**: for LCA of buildings where construction has already been completed/finalised. Usually used after the Final Design has been defined. A more challenging stage to identify further improvement strategies as the building as already been constructed. If conducting a foot-printing assessment, please use this design purpose.
- Audit: normally used at the final LCA stage when conducting an LCA for auditing purposes to calculate the impacts of real-world performance or to compare against predicted studies. Usually based on an existing building and actual bills and monitored data.
** The structure can only include one design with this purpose.
