eToolLCD Certification Service (Third Party Review)

Ever since the early days of eTool back in 2012 we highlighted one of the risks to widespread LCA adoption is the varying levels of quality in building LCA models and subsequent loss in confidence of the results and conclusions drawn.

To mitigate this, as well as our free of charge eToolLCD training, eTool have also ingrained a formal certification process provided with any paid for eToolLCD Subscription and associated project access fee. ISO 14040 and ISO 14044 standards for LCA call for all studies to be verified by a third party, therefore it made sense for eTool to offer this certification service, as we understand the inner workings of the software which is important for LCA verification. This approach allows eTool to carefully manage the user experience enhancing the users LCA writing skills by assessing users ‘inputs, whilst ensuring quality and comparability.

During the certification process, a senior eTool LCD practitioner is made available to your project for the purposes of:

  • Assisting the LCA team with completing the study in compliance with relevant standards and rating systems (we have now completed over 400 projects for BREEAM, LEED and Green Star so will ensure the model is completed to the correct requirements and no hold ups occur during the LCA credit  verification).
  • Providing credit for “3rd party verification” under BREEAM 2018.
  • Reducing the risk to your clients and elevating the professionalism of your service by peer-reviewing your LCA study to ISO 14040 and ISO14044 standards.
  • Assisting the LCA team with challenging concepts or modelling requirements.
  • Improving the LCA teams efficiency in completing LCA/LCCs using eToolLCD.
  • Providing the LCA team with potential strategies that may be worth considering to reduce the impact of the design.

The certifier will be “suitably qualified” to undertake peer reviews having as a minimum:

  • Completed at least 3 paid for LCAs within the last 2 years
  • eToolLCD advanced training course
  • Experience or qualifications in interpreting construction documentation

The certification system ensures that consistent, high-quality LCA studies are produced from the eToolLCD software. This lends further credibility to your work when clients see the eTool brand on your reports. Outcomes after initial certification requests and interaction with a senior eTool LCD practitioner during third party review has seen a considerable difference in tCO2e saved.

For practiced users of eToolLCD, our certification system offers the benefit of a dedicated support section to complement existing experience. Utilising our certification system, users will benefit from a very quick third party review and subsequent certification, due to the level of quality input data.  

The certification is provided for up to 6 designs within an eToolLCD Building or Infrastructure entity. These designs may be very early stage models, or later stage complete LCA/LCC models or a combination, typically:

  • Concept Design Stage Base Model
  • Concept Design Stage Improved Model(s) (including optioneering)
  • Concept Design Stage Final Model
  • Technical Design Stage Base Model
  • Technical Design Stage Improved Model(s) (including optioneering)
  • Technical Design Stage Final Model

eTool understands that good LCA/LCC modelling is an iterative process and will be on-hand from the outset to provide assistance and answer any questions surrounding the modelling and certification.

Certification Process:

  1. eToolLCD user conducts self review and submits initial model for review
  2. eTool staff complete quality checks on eToolLCD model and provides feedback
  3. eToolLCD user complete / update eToolLCD model
  4. eToolLCD user submit final model for certification
  5. eTool staff completes certification and issue Certifier Review Statement

BREEAM Third Party Verification

In addition to ISO14040 and ISO 14044 quality checks the certifier will also review the following for both baseline models and optioneering models, in line with BREEAM 2018 requirements:

  • Material quantities are within +-10% of those shown in design documentation (both concept and technical design stage models)
  • Where default figures for product service life, transport distance and construction waste have been adapted from generic material default values, there is adequate justification and references.
  • Adhesives are included if cover more than 20% of materials surface
  •  Study period of 60 years

The deliverables are as follows:

  •  eToolLCD Certifier Review Statement documenting checks made, comments and user responses using the certification checklist
  • Phone/email and web link support throughout the process.

Additional information can be found at the Subscription, Project Licenses and Project Certification sections of eToolLCD Software Use Terms and Conditions and eTool Services Specification.

Additional information regarding eToolLCD Project Access Fees can be found here.

* Effective modelling and certification is a result of the eToolLCD software being utilised as it has been designed/intended to be used. The certification service helps ensure that eToolLCD software is appropriately used by ensuring a high quality of user inputs. Studies are conducted by the author (not eTool), and if deviated away from standard processes, are exposed to the risk of errors in the model and authors adding information without notifying the reviewer. In these circumstances the reviewer will flag any concerns in the certifier review statement, but can not be held liable for inaccurate reports.
** It should be noted that as the review has not been conducted by a panel of experts, publication of the comparative results of the LCA would breach ISO 14044 and EN15978 unless the relevant sections of the standards were addressed, in particular requiring a panel review team for comparative studies. 
*** Users who wish to make eToolLCD results public, will also be required to provide a Third Party Verified LCA compliant report.

The new London Plan – How to meet its requirements

After its initial publication way back in 2017, and after many modifications, the new London Plan came into effect on 2nd March 2021.  One of the key directives is the use of Whole Life Carbon Assessments in an endeavour to meet net zero carbon commitments. In this article we look at what the new London Plan means for “Major Referable Projects” and how eToolLCD can be utilised in accordance with the new London Plan.

eToolLCD GLA Approved

Firstly, it is important to highlight that the GLA guidance requires that Whole Life-Cycle Carbon Assessments should be carried out using a nationally recognised assessment methodology. eTool are proud to announce that eToolLCD is one of the tools approved by the GLA. Some of the key benefits to using eToolLCD for your Whole Life-Cycle Carbon Assessments include:

  • Detailed support article on how to produce results and fill out the required submission template
  • SAP10 and Future decarbonisation grids already available in the software
  • All life cycle modules including module D
  • Biogenic carbon reported separately (EN15804 +A2 compliant)
  • Various end of life scenarios to choose from
  • All other software features listed in our subscriptions page

The London Plan – Overview

With an objective of becoming a net zero-carbon city by 2050, the London Plan is the statutory Spatial Development Strategy for Greater London and the 32 London boroughs, and is prepared by the Mayor of London in accordance with the Greater London Authority (GLA). All major projects are required to meet the net zero carbon target and must show an on-site reduction of at least 35 per cent beyond the baseline of Part L of the current Building Regulations.

Below references chapter 9 of the new London Plan, which covers Sustainable Infrastructure (SI). Policies SI 2 and SI 7 are the key policies with regards to the planning process for major developments.

Policy SI 2: Minimise Greenhouse gas emissions

Major development proposals should calculate and minimise carbon emissions from any other part of the development, including plant or equipment, that are not covered by Building Regulations, i.e. unregulated emissions.

Development proposals referable to the Mayor should calculate whole lifecycle carbon emissions through a nationally recognised Whole Life-Cycle Carbon Assessment and demonstrate actions taken to reduce life-cycle carbon emissions.

9.2.11 – Operational carbon emissions will make up a declining proportion of a development’s whole life-cycle carbon emissions as operational carbon targets become more stringent. To fully capture a development’s carbon impact, a whole life-cycle approach is needed to capture its unregulated emissions (i.e. those associated with cooking and small appliances), its embodied emissions (i.e. those associated with raw material extraction, manufacture and transport of building materials and construction) and emissions associated with maintenance, repair and replacement as well as dismantling, demolition and eventual material disposal). Whole life-cycle carbon emission assessments are therefore required for development proposals referable to the Mayor (more information on referable applications below).

Major non-referable development should calculate unregulated emissions and are encouraged to undertake whole life-cycle carbon assessments. The approach to whole life-cycle carbon emissions assessments, including when they should take place, what they should contain and how information should be reported, will be set out in guidance.

Policy SI 7:  Reducing waste and supporting the circular economy

Referable applications should promote circular economy outcomes and aim to be net zero-waste. A Circular Economy Statement should be submitted, for all major projects to demonstrate:

1) How all materials arising from demolition and remediation works will be re-used and/or recycled

2) How the proposal’s design and construction will reduce material demands and enable building materials, components and products to be disassembled and re-used at the end of their useful life

3) Opportunities for managing as much waste as possible on site

4) Adequate and easily accessible storage space and collection systems to support recycling and re-use

5) How much waste the proposal is expected to generate, and how and where the waste will be managed in accordance with the waste hierarchy

6) How performance will be monitored and reported

Referable applications

Under the requirements of the London Plan, any major developments that fall under a specific criterion require a referral to the Mayor of London. The criteria include schemes of 150 homes or more. They will also cover projects over 100,000 square metres in the City of London, 20,000 square metres in central boroughs or 15,000 square metres in outer boroughs.

Buildings that are over 25 metres in height within the Thames Policy Area, 150 metres in height elsewhere in the City of London and 30 metres in height elsewhere in London will also be referable.

When to submit a Whole Life-Cycle Carbon Assessment

Whole Life Carbon Assessments should cover the development’s carbon emissions over its life-time, accounting for both operational and embodied carbon and any future potential carbon emissions ‘benefits’, post ‘end of life’, including benefits from reuse and recycling of building structure and materials. (as mentioned in London Plan Policy SI 7 ‘Reducing waste and supporting the circular economy’).

The GLA guidance on Whole Life-Cycle Carbon Assessments follows the European Standard for measuring building performance – EN 15978 and the also RICS Professional Statement: Whole Life Carbon assessment for the built environment. It is also prudent to mention that RIBA (Royal Institute of British Architects) have also adopted the RICS Professional Statement (more information can be found in this paper by RIBA).

Planning applicants are required to submit a WLC assessment at the following stages:

  • Pre-application 

General information about the project site and a questionnaire with details of the Whole Life-Cycle Reduction principles.

  • Stage 1 submission (i.e. RIBA Stage 2/3)

A baseline WLC assessment should cover the entirety of modules A, B, C and D to comply with Policy SI 2. With regards to grid decarbonisation , applicants should provide two sets of WLC emission figures. The first set of figures will be based on the current status of the electricity grid, and the second set of figures should be based on the expected decarbonisation of the electricity grid over the lifetime of the development. Details on material type, quantity and end of life scenarios are also required.

  • Post-construction (i.e. upon commencement of RIBA Stage 6 and prior to the building being handed over, if applicable) 

Update of the information provided at planning stage and actual WLC results using material quantities and site emissions during construction. Generally, it would be expected that the assessment would be received three months post-construction.

A Whole Life-Cycle Assessment draft guidance and draft template is currently under development which comprises all of the information applicants will need to submit at each stage. This template should be completed and submitted to the GLA to ensure clarity and transparency.

How eToolLCD can be utilised to conduct Whole Life-Cycle Carbon Assessment in accordance with the new London Plan

Pre-application stage

  • eToolLCD  provides users the ability to produce models at concept stage and provide early design advice (see this article on Target Setting)
  • eToolLCD benchmarks available in the software library to assist the design team during the concept stage.

Planning submission stage

  • WLC Assessment Reporting Template – At eTool, we have reviewed the WLC Assessment reporting template and have prepared an eToolLCD to GLA WLC Report Spreadsheet to help our users populate the results for Assessment 1 and Assessment 2 at the Outline Planning and Detailed Planning stages.
  • EN 15978 – eToolLCD is fully compliant with BS EN 15978 including all life cycle stages A, B, C and D.

  • RICS – eToolLCD allows consultants to adhere to the application of the RICS Whole of Life Carbon Assessment for the Built Form professional statement. The following link gives a detailed summary of the “Must” requirements from the standard and associated detail on eToolLCD’s compliance.
  • Grid Decarbonisation – eToolLCD users can now calculate the operational impact of their projects considering the future decarbonisation of electricity grids
  • Scenarios – The Scenarios feature allows branching of design improvements. It gives the user the ability to define the starting point for the scenario and explore different routes for project changes. For example, understanding the difference from using Blast Furnace Slag versus Fly Ash as cement replacement in concrete. The benefit of this feature is the flexibility to model design strategies in parallel from different starting points, instead of a linear sequential order where an improvement is fully dependent on all previous changes. As the design progresses, the model can be adjusted with the appropriate starting point scenarios and the subsequent strategies can be considered, instead of having to remodel all recommendations again from the baseline design.

  • Design features – Advanced features will allow you to quantify, compare and improve the performance of your projects from early design stage through to detailed development. The following link will explain in further detail some of the advanced features in eToolLCD such as Templates, EPD, Bulk Swap, Recommendations recording and Analysis.
  • Materials Inventory Summary Report – quickly extracts material type and quantity to help fill out the reporting template. 

Post-Construction stage

  •  eToolLCD Automated Reporting – Understand the modelling results at different stages of the life cycle design process through eToolLCD automated reporting functionality.

How eToolLCD can be utilised to support Policy Sl 7: Reducing waste and supporting the circular economy, in accordance with the new London Plan.

  • Materials Efficiency Metric – The eToolLCD Materials Efficiency Metric was created to calculate material circularity and apply it to a whole asset analysis. The metric is calculated based on the mass of material that is virgin or reused, and the amount of renewable and non-renewable primary and secondary material.

The draft “Whole of Life Cycle Carbon Assessment Guidance”, was formally consulted at the beginning of 2021. Responses are currently being analysed, with final guidance due to be published later this year. eTool will release further information regarding this topic and what it means for eToolLCD users as the final guidance is released.

eTool Webinar (Youtube)




London Plan Policy – Targeting a reduction in building life cycle carbon emissions.


In response to the latest Draft London Plan Policy, eTool takes a closer look at the importance of Whole Life-Cycle Carbon Assessments (WLC) and the latest guidance.

Draft London Plan Policy SI 2 sets out a requirement for developments to calculate and reduce WLC emissions. This requirement applies to planning applications which are referred to the Mayor, but WLC assessments are encouraged for all major applications. Guidance has been published to explain how the assessment of these carbon emissions should be approached and presented, and all planning applications referred to the Mayor must include a WLC assessment prepared in accordance with the WLC guidance document.(¹)

National Building Regulations and the Mayor’s net zero-carbon target for new development currently only account for a building’s operational carbon emissions. As methods and approaches for reducing operational emissions have become better understood, and as targets have become more stringent, these emissions are now beginning to make up a declining proportion of a development’s WLC emissions. Attention now needs to turn to WLC to incorporate the embodied emissions of a development.(2)

Whole Life-Cycle Carbon (WLC) emissions are the carbon emissions resulting from the materials, construction and the use of a building over its entire life, including its demolition and disposal. It is widely accepted that a WLC assessment provides a true picture of a building’s carbon impact on the environment.

Applicants should use benchmarks figures provided as a guide for the design team. Projects with higher emissions should discuss design improvements to reduce emissions early in the concept stage. Aspirational targets are encouraged in line with the World Green Building Council reduction of 40% embodied carbon emissions by 2030. 

eTool makes the Office Benchmark model available online for all eToolLCD users, including Open Users, to encourage design teams to engage LCA early in the design process. eTool Benchmark figures are closely aligned with the Policy Benchmarks as detailed below.

TableClick here to create an account and check the model online for more details. eToolLCD Benchmark model available online includes all modules.

What methodology should be used?

WLC assessments should be carried out using a nationally recognised assessment methodology.

In the UK, the recognised framework for appraising environmental impacts of the built environment is BS EN 15978. This standard was adopted for use by eTool since its release in 2011 (this article expands on EN 15978 further: ).

Supporting the BS EN 15978 is the now widely used RICS Professional Statement: Whole Life Carbon assessment for the built environment(3). It is this RICS policy that should be used as the methodology for assessment when developing a WLC assessment for compliance with Draft London Plan Policy SI 2 (this article explains how eToolLCD adheres to the RICS Professional Statement: Whole Life Carbon assessment )

Both BS EN 15978 and the RICS Professional Statement: Whole Life Carbon assessment for the built environment, set out four stages in the life of a typical project and It effectively defines the goal, scope and method of the system boundary.


A WLC assessment should cover the entirety of modules A, B, C and D to comply with the London Plan Policy SI 2, with a reference study period (assumed life expectancy of a building) of 60 years.

What about materials and products?

With regards to acceptable sources of carbon data for materials and products, there is an emphasis on EPD’s and equivalent datasets in accordance with EN 15804, ISO 21930, ISO 14067, ISO 14025, ISO 14040/14044 and PAS 2050.

When it comes to biogenic carbon from the use of timber, this should be assessed in accordance with Clause 3.4.1 of the RICS Professional Statement: Whole Life Carbon assessment for the built environment, and included within the reported totals for modules A1-A3.

Grid decarbonisation

Figures should be based on the current status of the electricity grid, in order to provide a point in time assessment, however it is also important to consider the possible long term decarbonisation of the grid and how it could impact design decisions. Therefore, a second set of figures should be provided based on the expected decarbonisation of the electricity grid over the lifetime of the development (i.e. 60 years). This should be done in accordance with the ‘National Grid’s Future Energy Scenario: Slow progression’, including in relation to the EPDs of all materials (UK and non-UK, for simplicity)(4)

eTool will continue to work with UK Industry Bodies and working groups to offer our ongoing support on the above subject and guidance relating to Life Cycle Design.



What is a Zero Carbon Building?

What does “Zero Carbon” mean?  We thought we’d post this for clarity, when eTool make a claim about one of our subscriber’s (or client’s) buildings we aren’t cutting corners. When we use phrases like “Zero Carbon”, “Low Carbon” etc we’re talking about the Life Cycle Emissions of the buildings.  The normal scope is summarised in the following system boundary diagram (which also works pretty well for infrastructure as well).


eToolLCD System Boundary

eToolLCD System Boundary

There’s a number of varying definitions for “Zero Carbon” in use.  In Europe (including the UK) it’s generally only inclusive of module B6 in the above diagram (that’s integrated equipment energy use in the building) which is very limited.  Some more detail on the varied definitions is available from these two downloads (there are a host more such studies / reports / articles on the internet, this is just a sample):

What is a “Carbon Neutral” Building? Light House Sustainable Building Centre Defining Zero Carbon Buildings – ASBEC

Defining Zero Carbon Buildings – ASBEC


One Brighton Life Cycle Assessment Report

eTool completed a post construction Life Cycle Assessment of the One Brighton development the report can be found below.  The assessment provided some interesting results and lessons surrounding materials choice and centralised biomass heating.

BioRegional One Brighton Lifecycle assessment report final

Project: One Brighton

Client: Bioregional

Benchmarking Best Practice Residential Green Buildings

Executive Summary

How green are green buildings?  The question is very subjective but if we approach it purely scientifically there’s a way to (kind of) answer this.  The method was to measure the environmental savings of best practice conceptual green buildings against EN15978:Sustainability of construction works. Assessment of environmental performance of buildings. Calculation method.

The results are summarised in the below chart showing Global Warming Potential (GWP) performance (more indicators shown in the report).

Summary Chart 2

The main findings were:

  • Green buildings that focus entirely on non-greenhouse gas (GHG) related credits within rating tools (as far as is possible) achieved a 28-29% greenhouse gas saving against the benchmark
  • Those that focus entirely on GHG related credits will save between 65 and 77%
  • The large range in values was surprising but reflects the many green building credits that don’t relate to GHG savings in the EN15978 scope
  • The taller the building the more difficult it is to get large savings due to space limitations for onsite renewable generation
  • There were no significant poor trade offs in the Low Carbon focussed green buildings when other environmental indicators were analysed
  • The scope of EN15978 doesn’t include the below items which may also have a significant impact on overall GWP performance of the development, all of which can be influenced to some extent by building design (and some green building credits aim to do this):
    • Occupant transport
    • Occupant food and consumable goods consumption
    • Occupant waste generation


The green building movement has been very successful globally.  Uptake is incredible particularly considering most of these rating systems are voluntary for developers.  eTool is in awe at how the Green Building Councils motivated the industry to do better and in some sectors has totally redefined what is considered “normal”, significantly lifting sustainable design standards.   And it’s not only buildings that have benefited.  A whole generation of green building professionals have spawned from the design improvement requirements that the rating systems demand.  The green building movement has been an incredible success.

Despite this success there’s an underlying question that many people are now answering and that is “how green are green buildings?”.  Answering this question historically has largely been achieved by arguing relative values of different “green” credentials but with internationally recognised standards now available that measure the environmental performance of buildings, there’s actually a scientific approach to measuring greenness.

But care must be taken as greenness isn’t just about the planet, at least not anymore.  Typical green building rating tools now also look at social and economic sustainability, not just environmental performance.  In this post we are purely looking at environmental performance.  More specifically we will be focussing on Greenhouse Gas emissions (GHG) but also report performance against a number of other environmental indicators.


The aim of this exercise is to determine how much GHG emissions are avoided for best-practice green buildings compared to business-as-normal buildings.  eTool decided to conduct this research  to prevent any poor environmental trade offs associated with an organisations decide between a rating system and environmental impact targets.


It’s very difficult to compare rating systems, and perhaps impossible to do this in a fair manner.  It’s important to note that what follows is not a holistic benchmarking exercise, but rather just seeks to understand the environmental performance of green buildings.  Although this should be a simple process there are some complexities that warrant discussion.

The Rating Tools

Each major green building rating tool attempts to define environmental, social and/or economic performance (or all three).  At first glance most of the major tools look very similar.  They have criteria that leads to a scoring system that leads to some kind of recognisable rating.  On closer inspection however, depending on why, how and when each tool was set up, the weightings applied to different areas of sustainability vary significantly.  The illustration below shows how the weighting varies between the predominant rating tool in Australia and Germany.  The Australian “Green Star” system has a much higher environmental weighting and largely skips any direct credit for economic sustainability.  This is typical of most most green building rating tools around the world.  The DGNB system on the other hand gives equal weighting to each of the three areas (economic, social and environmental).

DGNB v Green Star

Having established these differences there is generally a bit of a convergence in the language when the final rating is communicated.  In the case of Green Star, the highest rating of six stars equates to world leadership and this seems to be goal of each rating system’s top rating, to recognise excellence on a global scale.

The Standards

Since 2005 the European Committee for Standardisation has been tackling the job of measuring building sustainability.  The work is being conducted by Technical Committee 350.  Specifically their task is to establish standardized methods for the assessment of the sustainability aspects of new and existing construction works and for creating standards for the environmental product declaration of construction products.  At the building level they are writing (or have written) standards to measure the performance of buildings in the following areas:

  • Environmental
  • Economic
  • Social

In this post we’ll be drawing on the environmental performance standards, specifically EN15978:Sustainability of construction works. Assessment of environmental performance of buildings. Calculation method.  Note that the standard is very building design focussed, the system boundary, shown below, doesn’t include building occupant transport, occupant food consumption, or occupant waste generation.  eTool have attempted to expand the scope as much as possible within the limits of the standard by including non-integrated operational energy use.


Building Characteristics

Different buildings inherently perform differently when looking at life cycle impacts.  The key factors are:

  • Energy intensity of the building use per unit of floor area (for example office verse residential use)
  • The site and building geometry characteristics that dictate renewable energy capture (mainly solar)
  • Climate zone which effects heating and cooling loads, natural daylight, available solar radiation and mains water inlet temperature

To account for these anomalies we’re modelling a range of characteristics to understand how they effect results.  Initially however we’ve restricted the climate zone to residential buildings, Building Codes of Australia climate zone 5 (Sydney, Perth), which we will likely expand, get in touch if you’re interested in seeing these results.


The basic methodology was to create a conceptual “standard” apartment building which represented “business as normal” delivery of apartment dwellings in Australia.  The quality of the construction including energy efficiency etc was to match construction code compliance levels.  This set a baseline for performance (this is different from the benchmark as it’s more location and geometrically representative).  This basic apartment building model was then upgraded by applying changes in eToolLCD to reflect changes that would need to be made to achieve a best practice green building rating.

We have chosen the Green Building Council of Australia’s Green Star rating tool as our case study as it’s local to eTool, very transparent and is fairly well aligned with other leading global rating systems.  Because we want to understand what world leadership means in terms of life cycle GHG savings, we are modelling theoretical buildings which would achieve a 6 star rating in the Green Star system.

Due to the range of credit criteria that span non-GHG related issues as well as those that relate directly to reduced GHG we have modelled the extremes.  The process to achieve this was:

  • Identify how the rating tool credits relate to GHG savings within the scope of EN15978 and categorise as follows:
    1. have a direct relationship on GHG reduction
    2. are partially or indirectly related to GHG reduction
    3. are largely unrelated to GHG reduction
  • Based on the building characteristics we determine the feasible limit of points that may be practically obtained for each credit * (see note)
  • To determine the “best case” GHG performance we model credits category 1 (direct GHG relationship), followed by 2 and lastly 3 (unrelated to GHG relationship) until we have achieved the required points for the top rating (Green Star 6 Star).
  • To determine the “worst case” GHG performance we model the credits in category 3 first, then 2 and lastly 1 until we have achieved the top rating.

For each building modelled this provides a range of possible GHG performance outcomes for the top rating.  The details on how we categorised the credits is found in a table in the appendices.

*NOTE: In some cases all available credits in a given category could not be feasibly achieved.  For example, for some buildings it’s not feasible to achieve a 100% reduction in operational energy related GHG emissions (worth over 20% of the Green Star rating).  In this case we estimated the maximum possible energy demand reduction and the maximum possible on-site renewable generation and determined the operational GHG savings based on this.

The buildings we chose to model are:

  • 5 Story
    • 25% of roof area lost to set backs or landscaping (unusual but possible best case solar capture potential)
    • 50% of roof area lost to set backs or landscaping (typical)
  • 15 Story
    • 25% of roof area lost to set backs or landscaping (unusual but possible best case solar capture potential)
    • 50% of roof area lost to set backs or landscaping (typical)
  • 25 Story
    • 25% of roof area lost to set backs or landscaping (unusual but possible best case solar capture potential)
    • 50% of roof area lost to set backs or landscaping (typical)
  • The benchmark buildings we chose to measure the GHG savings against are the eTool International Developed Country benchmarks.


No methodology is flawless so we wanted to highlight the potential pit falls in the below list:

  • eTool may not be aware of technologies or approaches that enable an increase in the number of points that can be achieved for a particular credit over and above our “feasible limit”.
  • We have had to make assumptions on building use profiles
  • This is building design and hence predictive approach rather than an empirical approach to measuring actual building performance
  • The Green Star tool has an “Innovation” category which accounts for up to 10% of the rating score. This category is quite flexible in how the points are awarded and may effectively increase or decrease the GHG savings.
  • The scope of EN15978 is very building centric, it doesn’t include for example occupant transport which is going to have a large effect on the GHG (if improved through better building design).  Depending on the savings facilitated by applying the green building transport related credits, the overall saving in GHG per person per year may be substantially different and the comparison may change between designs.


The code compliant apartment building represented an 18-19% saving compared to the international benchmark.  The taller building had a slightly better saving than the shorter building mainly due to some efficiencies in shared spaces.  The main differences between the benchmark and this baseline apartment building were that the base line building had:

  • Less heating loads (Benchmark includes regions like North America, Europe etc where as Australian climate is much, much milder)
  • Longer design life (Benchmark has a mix of densities which average less than the baseline)
  • Larger floor plate per occupant (particularly car parks, common areas, outdoor areas) and hence more operational energy to light and ventilate the building per occupant

Green buildings that focus entirely on non-GHG related credits (as far as is possible) achieved a 28-29% greenhouse gas saving against the benchmark.  Those that focus entirely on GHG related credits will save between 65 and 77%.  The large range in values was surprising but reflects the Green Building credits that don’t relate to GHG savings in the EN15978 scope.  The taller the building the more difficult it is to get large savings due to space limitations for onsite renewable generation.  A summary of the results is given in the below chart:

Summary Chart 2


It should be noted that the GHG focussed Green Building  is very aspirational and includes such strategies as biomass boilers for hot water and space heating, 9 or 10 star NatHERS performance and 20% reduction in the car park size.  The full list of strategies that were modelled that produced these results are given in the appendices.

Other Environmental Impact Results

To help determine if there were any poor trade-offs environmentally a host of other indicators were also predicted in the LCA.  These other environmental indicators are not as robust as the GHG figures due to less research effort and hence lower quality background LCI data.  They do however provide some basis for understanding relative impacts between designs.  Interestingly the results for other environmental indicators support the strategy of focusing on GHG savings as there’s generally a positive outcome.  The only poor trade off was a very slight increase in POCP due to combustion of timber as a low carbon heat source (for domestic hot water and space heating).  The 5 storey and 15 storey apartment building results are both very similar.

15 Storey Apartment Building LCA Impact Assessment for Multiple environmental Indicators

 2015.06.08 15 Storey Apartment Building, Multi Indicator Radar Chart Green Star 6 Star GHG Savings Focussed (Standard Roof)


5 Storey Apartment Building LCA Impact Assessment for Multiple environmental Indicators

2015.06.08 5 Storey Apartment Building, Multi Indicator Radar Chart Green Star 6 Star GHG Savings Focussed (Standard Roof)

The higher ecotoxicity result is due to increased copper use in the Green Star buildings.  This is an unexpected result but may be a reflection of poor background data (copper is by far the dominant ecotoxicity effect).  The reason for the higher copper in the Green Building models is replacement of PVC with copper and higher churn (longer building design life) for some copper in equipment.  This result could be seen as noise rather than a significant feature of the LCA impact assessment.


The main findings were:

  • Green buildings that focus entirely on non-greenhouse gas (GHG) related credits within rating tools (as far as is possible) achieved a 28-29% greenhouse gas saving against the benchmark
  • Those that focus entirely on GHG related credits will save between 65 and 77%
  • The large range in values was surprising but reflects the many green building credits that don’t relate to GHG savings in the EN15978 scope
  • The taller the building the more difficult it is to get large savings due to space limitations for onsite renewable generation
  • There were no significant poor trade offs in the Low Carbon focused green buildings when other environmental indicators were analysed
  • The scope of EN15978 doesn’t include the below items which may also have a significant impact on overall GWP performance of the development, all of which can be influenced to some extent by building design (and some green building credits aim to do this):
    • Occupant transport
    • Occupant food and consumable goods consumption
    • Occupant waste generation


Building Use Assumptions:

ABS Stats used to determine occupancy per bedroom in residential apartments

Assumed occupancy density of 15m2 / workstation in office buildings

Green Star Credit List and how each credit was applied to the LCA Model

Green Star Credits and Relationship to EN15978 Savings

More About the Conceptual Green Buildings:

The following strategies were modelled in eToolLCD software to determine the life cycle impacts of the conceptual green buildings:

  • Behavioural Change Initiatives Leading to a 5% reduction in building operational energy use through the application of the following credits:
    • Commissioning and tuning:
      • Services and Maintainability Review
      • Building Commissioning
      • Building Systems Tuning
      • Independent Commissioning Agent
    • Building Information:
      • Building Operations and Maintenance Information
      • Building User Information
      • Environmental Building Reporting
    • Commitment to Performance:
      • Environmental Building Reporting
  • Increase in end of life recycling recovery rates to 100% and where possible allocate waste to down cycling processes (rather than landfill, eg concrete recycling) through the application of the following credit:
    • Commitment to Performance, End of Life Waste Management
  • 100% reduction in potable water use via efficiency, rainwater collection and water recycling through the application of the following credits:.
    • Potable Water (This would require water recycling infrastructure and large rain water tanks etc to achieve which are modelled).
  • Energy monitoring upgrades lead to an additional 5% reduction in building operational energy use through the application of the following credits:
    • Metering and Monitoring:
      • Monitoring strategy
  • 50% reduction of construction waste through the application of the following credits:
    • Construction Environmental Management:
      • Formalised Environmental Management System
    • Construction and Demolition Waste:
      • Reduction of Construction and Demolition Waste
  • 20% Reduction in car park size through the application of the following credits:
    • Sustainable Transport:
      • Modelled pathway (reduction in number of car spaces and provision of alternative transport methods)
  • 100% recycled content steel through the application of the following credit:
    • Sustainable Products
  • Reduction in operational GHG through to the practical limit through application of the Green House Gas Emissions credit.  See section below on how this is applied.
  • Refrigerant change to CO2 which essentially negates any refrigerant impacts through the application of the following credit:
    • Refrigerant Impacts

Operational GHG Detail:

Operational GHG scope for residential buildings is all integrated loads in addition to the below items.  Also included in the below list is the maximum efficiency energy saving based on the most efficient MEPS rated products for each appliance:
  • Fridge / freezer (40% energy saving achievable for 10 years)
  • Dishwasher (35% energy saving achievable for 10 years)
  • Clothes washer (80% energy saving achievable for 5 years)
  • Clothes dryer (56% energy saving achievable for 5 years)
Individual strategies that were applied to achieve the lowest possible operational GHG savings:
  • Reduced fridge space (10.3% drop in average refrigerator energy use for primary refrigerator)
  • Improved fridge ventilation (See Basix requirements, 12.5% saving in refrigerator energy assumed)
  • 9 or 10 star NatHERS rating.  Cooling supplimented with ceiling fans and heating conducted with biomass (effectively zero carbon)
  • Water heating supplied with biomass and/or waste heat
  • Common area and car park lighting on 1 minute delay motion sensors and also automatically shut down when required lux levels are achieved by other light sources (natural or other artificial light)
  • Lighting Coefficient of utilisation improved due to colour scheme in building areas:
    • 0.6 Achieved in car park with white concrete or painted white floors and walls
    • 0.8 Achieved in apartments
  • High efficiency lamps, ballasts and fittings installed throughout
  • Regenerative drive elevators with auto shut down of controls and lighting when not in use
  • Cooking energy supplied by gas (stove and oven)
  • Engineered CFD modelled car park vent solution saving 70% of energy8
The efficiency improvements associated with these items is only applied over the life of the first product installed.  Other strategies (such as refrigerator space and ventilation) are assumed permanent over the building’s life.

The “Peak Electricity Demand Reduction” credit is likely to effect EN15978 results depending on how it is achieved.  If batteries are utilised it would likely increase the net impacts of the buildings.  For this reason the credit has not been modelled to ensure the results reflect the performance of the Green Building positively.

eTool LCA reveals 60% carbon cut for One Brighton

eTool LCA identifies dramatic carbon savings in leading UK development 

A life cycle assessment by eTool reveals UK-based BioRegional’s One Brighton project is delivering a 60 per cent reduction in greenhouse gas emissions compared to the average UK home with the potential to achieve up to almost an 80 per cent reduction.

The impressive findings from eTool’s in-depth life cycle assessment for the inner city apartment development were recently released to a flurry of interest during the UK Green Buildings Council’s Embodied Carbon Week.

eTool’s LCA includes the embodied carbon emissions within this pioneering mixed-use and car-free twin block development, as well as One Brighton’s day-to-day operational emissions from energy and water consumption. As with all eTool LCAs, they are conducted with eTool’s unique online software, giving international standard EN 15978 compliant outputs.

eTool has also worked with BioRegional Australia on projects such as the 5×4 Hayes Lane project located in Melbourne, which was designed in accordance to One Planet Living principles. eTool software was used to calculate and optimise the full life cycle impacts of the project. eTool can assist projects in achieving endorsement against One Planet Living.

Pooran Desai, OBE, BioRegional co-founder, said: ”The Carbon LCA carried out by eTool shed new light on our environmental strategy at One Brighton. It has given us a clearer insight into the relative importance of embodied versus operational greenhouse gas emissions which will inform our next One Planet Community. Carbon LCA has come of age and eTool are right at the forefront of this very useful approach to measuring environmental impact.”

One Brighton was completed and occupied in 2010 and eTool’s LCA was an important part of the review of its performance against the targets set in the One Planet Action Plan. The One Brighton is Bio Regional’s follow-up multi-residential project to the world famous BedZed eco-village in Sutton, South London.

Pat Hermon, lead eTool LCA engineer, said: “An LCA never fails to raise interesting design questions surrounding not only material selection but operational energy, water, transport, waste and functionality. This LCA of One Brighton is no exception, particularly thanks to the transparency of the developers and post-occupancy monitoring – an important step forwards in closing the performance gap.”


The findings from the One Brighton LCA report and the project’s sustainability credentials have received a lot of attention in the UK. Read more about the project here:

One Brighton releases 60% fewer emissions – Building 4 Change, BRE Trust, UK

One Brighton: Achieving a 60% carbon cut, aiming for 78% – UK Green Building Council

One Brighton achieves deep carbon cuts  – Global Sustain, UK

BioRegional project delivers 60% carbon savings –

eTool is watching with interest as BioRegional continues its work to reduce OneBrighton’s operational emissions in order to reach its 2020 target.


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Please note: High-resolution images and interviews are available on request.


Media contact:

Portia Odell
eTool Marketing Communications Manager
+61 08 9467 1664

About eTool

eTool is a world leading life cycle software consultancy that optimises building design for lower environmental impact and high performance. Utilising our unique software eToolLCD®, we work with architects, engineers and developers to measure and improve the life cycle impacts of buildings, surpassing industry standards. eToolLCD® makes sustainable development easy to achieve and cost-effective for all size projects, from residential and commercial building to land development and infrastructure.
For more information, please visit You can also follow us on Twitter, join us on Facebook and LinkedIn for the latest eTool news, or read our blog.

The science behind eTool – Life Cycle Assessment

Embodied Energy Calculations within Life Cycle Analysis of Residential Buildings

“As energy costs increase, controlling the cost of living will require reductions in energy demand. Furthermore, managing global greenhouse gas emissions from property development is of key importance for minimising climate change. Life Cycle energy analysis clearly identifies optimum strategies for reducing both energy demand and greenhouse gas emissions…”

In this informative paper, Rich explains the principles behind LCA in the built environment.

Click here to download.