Who recognises LCA?

Life Cycle Assessment is recognised internationally in standards, rating tools and even legislation.


Life Cycle Assessment is recognised by the International Organisation for Standardisation (ISO) through standards 14040 and 14044 which deal directly with LCA.  LCA is also heavily referenced or relied upon in many other ISO standards covering environmental assessment of products, services, buildings and civil structures.  Essentially, when it comes to assessing environmental performance, ISO standards prefer the use of LCA.

The European Centre for Standardisation (CEN) also heavily rely on LCA for assessing the environmental performance of buildings and building products (standards EN15978 and EN15804 respectively).  These standards are quickly becoming recognised internationally.

Of course this all makes sense, when you do stand back and think carefully about how to guarantee that a design decision you’re making truly leads to a net improvement in performance, you need to understand the life cycle impacts associated with that decision.  It’s really the only way to be sure a design choice isn’t leading to poor trade off’s.  The technical committees that were tasked with standardising “Assessment of the Environmental Performance of Buildings” had many existing systems and approaches to choose from around the world.  LCA emerged as the best option available.

Building Rating Systems

The uptake of whole building life cycle assessment has been accelerating in recent times as it becomes  more practical to implement. Even existing rating systems are quickly embracing and integrating it into their systems.  These systems include:

  • US Green Building Council: LEED
  • Living Future Institute (US): Living Building Challenge
  • BioRegional (UK): One Planet Living
  • Green Building Initiative: Green Globes
  • German Sustainable Building Council (DGNB): DGNB System
  • Green Building Council of Australia: Green Star

LCA is utilised differently by these different systems.  In the case of the DGNB it’s a very significant part of the total scoring system, where as other systems are only just starting to introduce LCA.  Whole of building LCA has only become practical reasonably recently, and it’s uptake is accelerating, both in the number of systems that are incorporating it, and also the weighting.


Governments are beginning to recognise that the way we are running our economy is unsustainable, particularly with the issue of climate change. The world needs to reduce GHG emissions per capita by approximately 80%, and developed countries by 95% to achieve sustainable levels of greenhouse gas emissions. In the construction sector, although no regulations have yet specified LCA of whole buildings, this avenue is being seriously considered. Washington State Senate commissioned a study to explore the potential of integrating life cycle assessment methods, data and/or standards into the state building code. Findings supported implementation but not immediately as the industry needs time to develop LCA skills and data. External to building regulations a number of product labelling programs have also unfolded to introduce transparency regarding embodied carbon of products.  These programs rely on LCA to determine a product’s carbon footprint.  The following programs are all using LCA to quantify and compare environmental impacts of consumer products.

  • France introduced a national pilot program of LCA based environmental labelling under the Grenelle 2 Act.
  • South Korea initiated a carbon labelling program for consumer goods and services. The system is voluntary but instigated by “The Fundamental Law for Low Carbon Green Growth, 2010”. 600 goods and services currently certified and labelled.
  • Japan’s Ministry of Economy, Trade and Industry started a pilot labelling program in 2008. Over 300 retailers and manufacturers are involved across 53 product categories.
  • Thailand have introduced a pilot CO2 labelling program through the GHG Management Organisation. Launched in 2010, 458 products from 100 companies are carrying the label.

How much CO2 is the built environment responsible for?

A number of sources are now confirming the huge impact of buildings on the environment.
When both embodied and operational emissions are accounted for, most estimates seem to fall between 30 and 40%, although some studies indicate it is even higher.

“Worldwide, 30-40% of all primary energy is used in buildings.” United Nations Environmental Program, 2007

“The commercial and residential building sector accounts for 39% of carbon dioxide (CO2) emissions in the United States.” United States Green Building Council, 2009

“According to the U.S. Energy Information Administration (EIA), nearly half (46.7%) of all CO2 emissions in 2009 came from the Building Sector.” Architecture 2030, 2011

What is Life Cycle Assessment or “LCA”?

LCA is an accounting method that assesses each and every impact associated with all stages of a product or process over its life span. The approach is sometimes referred to as a “Cradle to Cradle” assessment if it accounts for full recycling at the end of the products design life or just “Cradle to Grave” if it takes the product through to disposal only.

For more details please download our paper on the science of LCA in the built form here.

How does LCA relate to the built environment in regards to energy and carbon?

LCA of the built form involves quantifying the total “Embodied Energy” and the “Operational Energy” over the entire design life of the building (click here to see LCA graphic). Energy can then be converted in CO2e using applicable coefficients relevant to the primary energy source and efficiency.

For more details please download our paper on the science of LCA in the built form here.

What does “Embodied Energy” mean in reference to the built environment?

Embodied Energy refers to the energy and/or carbon required to construct and maintain a building over its entire design life (click here to see LCA graphic).
Embodied Energy can be broken down into the following components:

  • Materials – Energy used to extract the raw materials and process them into useable building products available at the gate of the factory (“Cradle to Gate”).
  • Transport – Energy used to transport the building materials from the factory gate to the building site.
  • Assembly – Energy used to construct and create the building.
  • Recurring – Energy used to maintain and replace certain building elements over the entire life span of the building.
  • Demolition and Recycling – Energy used to demolish and recycle the building and feed the resultant materials back into the building materials “food chain”.

For more details please download our paper on the science of LCA in the built form here.

What does “Operational Energy” mean in reference to the built environment?

The “Operational Energy” is the amount of energy required to run the building over its design life and includes appliances such as Air-Conditioners, Hot Water systems, Refridgeration and Lighting.

How much “Embodied Energy” is there in an “average” building?

As there are limited numbers of LCA’s of buildings completed in Australia, the sample group is too small to quote what an “average” might be. However after conducting numerous LCA’s on “benchmark” or “standard” Australian residential designs we have found that “Embodied Energy” is responsible for approximately 35% of the a buildings carbon footprint.

As we rapidly populate our database of designs globally we will be better positioned to provide more accurate statistics on “average” values. To put this in perspective, in Australia air conditioning is responsible for approximately 23% of the buildings total carbon footrpint over its design life. With “Embodied Energy” at 35% we feel that it is imperative that the use of eTool and LCA compliment the legislated design requirements for the thermal performance of buildings in Australia.

How can LCA compare different types of buildings?

eTool have “Benchmark” buildings for different primary building uses.  Benchmarks are a weighted average calculation of embodied and operational carbon for the new buildings of that primary purpose.  For example, our residential benchmark reflects the new residential dwelling mix in Australia.  That is, we’ve looked at the national Australian Bureau of Statistics data for new dwellings, determined the mix of low, medium and high density buildings, established a weighted average size of dwelling and then determined the embodied carbon of that size of dwelling.  We have then profiled average energy consumption for new homes, adjusted for the climate region (which affects the thermal performance component).  We have ensured that all energy consumption stats are calculated on building code compliant structural, design and energy efficiency measures.  This gives us a measuring stick against which all new residential premises can be compared, our “Benchmark”.  Ideally we want to reduce the impact in comparison to this “average” for new dwellings.

The obvious question regarding the above approach is that we’re not comparing like for like. For example, how can we compare a detached house to a multistory residential apartment block?.  By using a functional unit of “impacts / occupant / year” we are normalising results to allow comparisons despite wildly varying building sizes, styles, densities etc.  Without the functional unit the eTool benchmark buildings would be useless to compare against.  The power of the functional unit is that it enables all buildings to be compared, thereby the advantages (or otherwise) of totally different housing approaches can be assessed against the “business as usual” approach.


Life Cycle Assessment (LCA) is covered by ISO 14040 and 14044; it is a method of assessing the environmental impacts of a product or service. LCCA (Life Cycle Cost Assessment) is covered by ISO 15686 – 5 and gives guidelines for performing life cycle cost analysis of buildings and constructed assets.
eToolLCD has been developed to meet LCA standards, and although is a very useful tool for life cycle cost assessments, the standard reports generated by eToolLCD don’t necessarily meet ISO 15686 – 5 (LCCA).  Neither of these standards are particularly well known and we have been providing both services to clients in the past to their satisfaction.

Do you account for building design life?

Absolutely, design life is a critical component of good LCA performance.  The studies suggest that for buildings, the actual service life is dictated by redevelopment pressure, not durability.  If it’s a detached residential building in a high density area it is likely to be subject to very high redevelopment pressure in the not to distant future.  If however a building is very high density, or in a very low density area it’s not going to be under nearly the same pressure for redevelopment.  Further to this, by applying good future proofing design principles and superior design quality, design life may also be extended.  In determining the environmental impacts of a building design life and functionality can be the biggest determinants.