EN 15978 and eTool LCA Normal System Boundary

EN 15978

In 2011 the European Committee for Standardisation (CEN) released a new standard for measuring the environmental sustainability of buildings.  We grabbed a copy of this standard, EN 15978 soon after it was published to understand how eTool stacked up against the requirements.  We breathed a sigh of relief, although we had a few things to tidy up, what we were happy with was that we actually needed to reduce the scope and system boundary of a normal eToolLCA to report to EN15978.

Background to EN15978

This standard was one of the first to be released by CEN Technical Committee 350.  It was part of a much broader project to fully define how to measure the sustainability of buildings.  Within TC 350 there were working groups determining how to measure a building’s:

  • Environmental Performance,
  • Social Performance, and
  • Economic Performance.

Impressive.  The full suite of sustainability covered under one set group of standards.  And it doesn’t stop there, there are also working groups covering civil works and construction products.  Incredibly, they are making very good headway through this arduous scope with 8 standards already published and another four under development.  EN15978 is the key to measuring the environmental pillar of sustainability.

How Does it Work?

Well, it’s kind of complex you have to read the detail of the standard, and a good number of the standards referenced.  That said, we will summarise as best we can.  The basic philosophy is to rely 100% on LCA as the method of measuring environmental performance.  So there is hence a heavy reliance on ISO 14040, 14044 and 14025 which eTool LCA software also heavily draws on.  The standard gives guidance on how to apply LCA to buildings.  It effectively defines the goal, scope and method for LCA practitioners working on buildings.

The System Boundary

The diagram below shows the system boundary of EN 15978 is shown below.  For existing users of eTool LCA, or those who rely on eTool ratings, our standard system boundary is also shown.  We think the EN 15978 have essentially done a fantastic job putting this together (with a few exceptions we discuss below).

EN 15978 and eTool LCA Normal System Boundary

EN 15978 and eTool LCA Normal System Boundary

The largest omission from the system boundary is what EN15978 calls “non building related energy use”.  They essentially include HVAC, domestic hot water and lighting but exclude all other energy used within the building.  This makes sense at first glance, after all, these areas are certainly the most heavily influenced by the building designers, and other energy use is very heavily occupant driven.  There are however some strong arguments for including all energy used within the building, a few of which are listed below:

  • A building designer can influence occupant behaviour, and as such these aspects should be considered by architects and engineers, for example:
    • Energy monitoring has been proven to influence occupant behaviour in both commercial and residential buildings and should be considered by the design team
    • In residential buildings, energy use per occupant generally drops off with higher occupants per dwellings due to the base loads (refrigeration, living area entertainment, standby loads, lighting and heat losses from hot water systems) being spread between more occupants.  Buildings that allow and encourage more occupants per dwelling will (all else being equal) use less energy per occupant, and hence should be differentiated.
    • In commercial buildings, an integrated fit out of work stations can have huge positive impacts on energy use through the use of central servers for data storage and processing and mini computers at work stations drawing very little power.  A seamless implementation of such systems may require architectural and engineering consideration during the design of the building so should be factored.
  • Building integrated renewable energy systems should if possible be sized to meet the entire load of the building, not just the base building loads, so designers should be aware of the entire loads.
  • Developers can have a large influence on the building performance (at least initially) through the final fit out of appliances (residential) and work stations (commercial) so this should be within scope so we don’t drop the ball on this opportunity.
  • Vertical transport (elevators, escalators etc) for medium rise buildings can be heavily influenced by design:
    • The building envelope needs to cater for the most efficient plant geometrically
    • The use of stairs or ramps should be encouraged through design to reduce reliance on plant
    • The building electrical systems should be designed to cater for regenerative drives etc
  • Communicating the total impact of buildings without accounting for occupant energy use is very misleading.  Imagine moving into a building marketed as ‘energy neutral’ building only to find your power bill only drops 25%

Environmental Indicators

The suggested list of reported indicators is quite comprehensive for EN15978 and is shown in the below summary table:

 EN15978 Indicators

EN15978 does state that not all indicators need to be reported, but the documentation must specify the reasons for omission.  Interestingly toxicity, land use, biodiversity are missing from the above list.  The standard states that this is due to there being no scientifically agreed calculation method within the context of LCA for these indicators.  We’ll watch this space as we know some of these missing indicators are of great interest to many users of eTool.

EN 15978 and eTool LCA

After we read EN15978, we documented the required changes, pushed them into our product roadmap we got back to other work.  It wasn’t for another year though before it hit us how important this standard was.  All of a sudden, we weren’t “those guys from Western Australia who think they’ve nutted out how to truly improve the environmental performance of buildings”, EN15978 established that LCA was indeed the most appropriate tool for profiling green buildings.  Standards such as this one lend huge credibility to solutions like eTool that were released prior to the standard.  We were definitely barking up the right tree when we naively stood in front of the cameras on the ABC’s New Inventors and demonstrated the humble beginnings of eTool!

The recent uptake of LCA by the Green Building Council of Australia in their Greenstar tool heavily references  EN15978.  This has prompted us to build a suite of reports that are compliant with the standard, and those it references.  Importantly, we’re not going to remove any functionality form eTool, or contract the scope or system boundary.  Users will simply have the opportunity to report to either the EN15978 scope or the more expansive eTool LCA scope.  Similarly we’ll continue to upload more indicators into eTool LCA, our focus for the next 12 months will be plugging the gaps for EN15978 reporting.  There’s likely to be a lot of low hanging fruit here, and some trickier ones that may take some additional programming so we’re not entirely sure when we’ll be reporting on all 22 indicators just yet.  Our reports will be compliant with EN15978 though by still listing these additional indicators with “INA” (Indicator Not Assessed) in place of the calculated values which is accepted in the standard.  We’ll also allow users to report indicators currently available in eTool that aren’t required by EN15978.  Our general position on indicators is that global warming is our biggest environmental problem and hence our main efforts will continue to focus on solving this.

2 replies
  1. eTool says:

    Hi Danny,

    Thanks for reading and thanks for your comments. CAD compatibility is pretty high on our list of priorities. See this post on our product road map, although it’s old, it’s still very relevant (we’ve since knocked off the first of the key milestones by aligning with relevant standards). http://etoolglobal.com/eblog/news/etool-lca-product-development-roadmap/

    We’re currently in a deep research phase working out how to implement 3D integration. There’s a number of options in front of us, AutoDesk being one. AutoDesk have actually invited us to integrate and we have had early discussion about how best to achieve this. The key finds from these discussions were:
    1) eTool think the platform that integrates with eToolLCD should have thermal modelling capabilities (and potentially even lighting energy calcs). AutoDesk agreed with this.
    2) eToolLCD is a design tool for improving environmental impacts, and much of the lowest hanging fruit is identified in very early stages of the design process. AutoDesk and eTool both agreed that an early stage design package was the best fit for eToolLCD to integrate with.
    Based on the above two points we’re looking at integrating with Vasari (http://autodeskvasari.com/) which will hopefully also give us good portability with Revit through export / import.

    Other than AutoDesk we’re also looking at other packages as well. The one protocol that is probably (tentatively) at the top of the list for us is enabling an import of an Energy Plus IDF file. This aligns really well with point 1 above, and has the advantage of being cross-platform in nature (in terms of CAD packages). For example, there are already a few methods of getting an IDF file from a Revit model (e.g. via Green Building Studio). This also opens the door for plugins either developed by eTool or third parties to simplify the process further.

    We do a lot of consulting using our own software. To date we’ve conducted about 200 LCAs on construction projects around the world. We track our consultants time fairly carefully and a really interesting fact is that we actually find the “area take off” part of an LCA study isn’t very time consuming. Particularly the part actually going from the CAD model into eTool, and this is the key area that would be helped by a 3D integration. So we actually don’t see this functionality as a big time saver. This finding was totally unexpected for us, quite counter intuitive, but the timesheet data stacks up when we checked it out. We’re still very motivated to integrate with CAD packages, but I thought I should note this so you don’t see the lack of CAD integration as a short term show-stopper.

    I’m a bit reluctant to directly compare eToolLCD to Tally because I’m obviously inherently biassed in that discussion, and have way, way more familiarity with eToolLCD than Tally. Needless to say, we are absolutely stoked that Tally has been developed. Yep, we said it, we’re pleased. The reason being is that we set eTool up to help the planet, and Tally is supporting the same aim. Life Cycle Assessment is going to become a popular practice, in ten years time it’ll be akin to today’s energy modelling discipline. I don’t want to down play Tally to “win users”, the LCA industry needs to win users as a whole more than eToolLCD needs to win market share! When the market matures a little we will publish a detailed comparison of eToolLCD verses our competition. In the mean time, eTool is free to trial, and I believe Tally is too, so my advice is to try them out. I am quite confident you won’t have to invest much time in eToolLCD to be up and running quite quickly and be able to make you’re own assessment.

    Thanks again for posting.


  2. Danny Lee says:

    Great stuff but what about the compatibility with BIM Autodesk Revit?A nd how does your tool compare with Tally plug-in for Revit?

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