Life Cycle Assessment may be used to support a Development Application with the City of Vincent, in particular to satisfy the requirements of the City of Vincent Planning and Building Policy Manual No. 7.1.1 Built Form.
Application of LCA to Policy Requirements
There are three parts of the City of Vincent Planning and Building Policy Manual No. 7.1.1 Built Form where eToolLCD LCA will be applicable. The other sections are best addressed qualitatively by the architect.
SINGLE DWELLINGS: Volume 1, Section 1 – Town Centre
MULTIPLE DWELLINGS AND MIXED USE: Volume 2, Section 1 – Town Centre
COMMERCIAL: Volume 3, Section 1 – Town Centre
Note the following clauses should be able to be satisfied with description from the architecture or designer.
Development shall incorporate:
(a)Site planning principles that maximise solar passive design opportunities for both summer and winter;
(b) Natural ventilation and daylight penetration to reduce energy consumption;
(c) Daytime areas with north-facing glazing to allow passive solar heating during winter;
(d) Openable windows and/or ceiling fans to habitable rooms or occupied spaces that allow natural and cross ventilation;
(e) Recovery and re-use of rainwater, storm water, grey water and/or black water for non-potable water applications;
(f) Shading devices to reduce unwanted solar gain in summer and increase passive solar gain in winter; and
(g)Integration of renewable energy and energy storage systems to optimise energy consumption.
In the past we have used a statement similar to the below to meet part (e):
Non-potable water use is minimal throughout the design due to the application of water efficient toilets, taps and showers and relatively small areas of irrigated plantings. The design team has identified water capture, grey and black water capture and treatment during the target setting workshop but did not preference these options due to:
- Low non-potable water use requirements of the development
- Logistical constraints, energy use and operational costs associated with grey and black water treatment in multiple dwelling complexes influenced heavily by health regulations (significant periodic inspection and testing required in multiple dwellings applications)
- Space requirements of rain water harvesting and/or grew and black water treatment tanks
- Relative cost vs benefit of these strategies versus competing strategies which delivered much larger environmental benefits at a lower cost
In summary the policy states that the study must comply with ISO 14044 and EN15978 and the development must demonstrate that is capable of achieving the environmental performance shown below:
Residential component: – Global warming potential of the development over its lifetime to be reduced by 50% or more when compared to the average Australian code-compliant equivalent building built at the same time. – Water use of the development over its lifetime to be reduced by 25% or more when compared to the average Australian code-compliant equivalent building built at the same time
Commercial & All Other Building Types component: – Global warming potential of the development over its lifetime to be reduced by 30% or more when compared to the average Australian code-compliant equivalent building built at the same time. – Water use of the development over its lifetime to be reduced by 25% or more when compared to the average Australian code-compliant equivalent building built at the same time.
This means that your Proposed Design must achieve the target savings against the AU benchmarks, not against your Business As Usual/Reference Design. For example, if your BAU/Reference Design is performing 15% worse than the AU Benchmark, your Proposed Design will need to achieve an additional 15% more savings in order to meet the target savings.
Options for Demonstrating Compliance
EN15978 Compliant LCA:
This is the original intended pathway for complying with the policy and involves completing a EN15978 compliant LCA to demonstrate the savings against the benchmark. There is no requirement for a factor of safety via this route.
To ensure the City of Vincent planners can easily interpret the report, the strategies that are being pursued must be clearly listed, and itemised in terms of their environmental savings. This allows planners to refer to a succinct list to check compliance against at the time of building permit or occupancy certificate.
City of Vincent Planners have become accustomed to the Target Setting reports so it is recommended that if utilising a full LCA a summary cover sheet is supplied to summarise the results.
In response to stakeholder feedback the City of Vincent explored means of reducing the consulting costs associated with conducting LCAs. After consulting with eTool and other stakeholders it was agreed that developers can conduct a “Target Setting” LCA to save consulting costs and time by instead of a full EN15978 compliant LCA on the following conditions:
- A 20% factor of safety for was applied on each improvement strategy on top of policy targets.
- The strategies that are being pursued are clearing listed in the Target Setting report so planners have a list to check compliance against at the time of building permit or occupancy certificate.
- The Target Setting is utilised prior to the DA.
It should be noted that if a developer decides to conduct a Target Setting assessment, the factor of safety considered will likely add to the initial capital costs related with building upgrades due to the factor of safety. The building however will likely perform better (better building, planet wins).
Please refer to this support post on fees & conditions of use for conducting Target Setting Studies.
Scope of the Study
The following table details the expected scope of the LCA study. Note the inclusion of B6+ (non-integrated operational energy, e.g. from plug loads) what ensures a wholistic assessment of the building in use phase.
|Life Cycle Stage||Detail Description||Code||In Scope|
|Construction Phases||Product Stage||A1-A3||Yes|
|Transport of Equipment and Materials||A4||Yes|
|Use Phases||Use of Products||B1||Yes|
|Integrated Operational Energy||B6||Yes|
|Other Operational Energy||B6+||Yes|
|Operational Water Use||B7||Yes|
|End of Life Phases||Deconstruction / Demolition||C1||Yes|
|Transport of Waste Offsite||C2||Yes|
|Benefits and Loads Beyond the System Boundary||Operational Energy Exports||D1||Yes|
|Closed Loop Recycling||D2||Yes|
|Open Loop Recycling||D3||Yes|
|Materials Energy Recovery||D4||Yes|
The inventory collection should be thorough and include all life cycle phases. To avoid negative trade offs when considering design options the impacts associated with construction, transport, maintenance and repair should be relevant to the materials and components used. It is not sufficient to apply a generic construction impact per square metre, assumed generic transport distance for all materials or assumed replacement interval and subsequently assess the benefits of timber construction verse concrete construction as this design decision will influence not only the material impacts but also transport, construction, maintenance, repair, replacement etc.
Similarly changes in energy efficiency should include modelling associated with material changes. For example, a design option to include motion sensors to reduce lighting energy should incorporate the materials, installation, replacement etc impacts also. Often these impacts will fall under the cut off rules but not always so it is prudent to model them appropriately.
Applying the EN15978 cut off rules necessitates the inclusion of inventory items such as refrigerants, finishes and in many cases finishes, electrical equipment, mechanical equipment and hydraulic installations.
To overcome the “performance gap” commonly found between building simulation and actual energy consumption the energy use should be calculated by taking empirical demand figures, determining end use energy (assumed splits) and applying “code compliant” improvements to each end use. The same approach should be taken for modelling the energy demand in the proposed building. If a theoretical energy use figure is used a custom benchmark should be modelled which also uses theoretical energy calculations. That is, comparing an eTool benchmark derived from a hybrid of empirical and theoretical data to a pure theoretical energy figure is not consistent and fails the data quality requirements within the standards.
City of Vincent requires that the proposed project is compared with an Average Australian code-compliant equivalent building. This is somewhat open to interpretation, eTool have interpreted this as follows.
Common Building Types (Residential and Office)
- To recognise functional improvements in the building (yield, occupancy, life span etc) the benchmark is an average of building types for the typology of the building rather than a Code Compliant version of the same building. For example, a residential benchmark is made up of of a statistical mix of building impacts as follows:
- 61% Detached
- 13% Semi Detached
- 7% Low Rise Apartments
- 19% High Rise Apartments
- This rewards a building with improved functionality or life span. For example:
- A very efficient car park design verse average (in terms of floor space), or
- Design features that will extend the building’s life span.
- The benchmarks are not an average of existing stock but rather an average of new stock. Hence any efficiency requirements etc in the Building Codes etc are taken into account. This means that periodically the benchmarks will improve in performance and the requirements will be harder to achieve.
- To overcome the “performance gap” commonly found between building simulation and actual energy consumption we have determined energy use by taking empirical demand figures, determining end use energy (assumed splits) and applying “code compliant” improvements to each end use. The same approach should be taken for modelling the energy demand in the proposed building.
The relevant LCA models are publicly available in the eToolLCD software. Please refer to this FAQ post on how to access these benchmarks.
Some additional guidance and discussion on benchmarks is provided here. Note that we’re aware that we’re due for a big update and spring clean of our benchmarks. At which point we will be sure to update this post.
Other Building Types
Where determining a statistical mix is more complex due to lack of previous studies a code compliant version of the same building type may be utilised.
For mixed use buildings apply the same 80/20 methodology that Green Star uses in determining whether the building is considered mixed use or not. For example, a building with 85% Residential floor area vs 15% Office floor area will not qualify as a mixed use building but a predominantly residential building, therefore the office component will be excluded from the scope and the project will be compared with the WA Residential Benchmark. This carries risk as in some cases very energy intensive parts of the building (e.g. cafes, retail etc) may use over five times the energy per square metre (so potentially the 20%, if included, would account for 50% of the impacts).
If associated with commercial gain, an independent review will need to be conducted for the Target Setting study in accordance with EN15978 and ISO 14044. Please refer to this post for details of the Certification Process.