This guidance document – the EeBGuide – provides information on calculation rules, metrics, provisions and instructions for LCA studies of energy-efficient buildings and building products for European research projects of the E2B Initiative. The core objective is to give pragmatic and relevant guidance to LCA practitioners and construction experts on how to move forward in the field of LCA towards comparative, meaningful study results, both within individual studies and between them.

This document is the outcome of the European research project ‘EeBGuide – Operational guidance for Life Cycle Assessment Studies of the Energy-Efficient Buildings Initiative’, which ran from November 2011 to October 2012. The project was co-funded as a coordination and support action (CSA) by the European Commission under the Seventh Framework Programme, contract no. 285490. The project was coordinated by the Fraunhofer Institute for Building Physics Sustainable Construction Group (Germany). Other members of the consortium were PE International AG (Germany), Centre Scientifique et Technique du Bâtiment (France), Escola Superior de Comerç International (Spain), BRE Global Ltd (UK) and Prof Ch Sjöström Consultancy (Sweden). As members of the review panel, Friderik Knéz and Dr Wolfram Trinius contributed to the development of the document, as well.

LCA studies are generally conducted for one specific scope. Within the construction sector, such a scope typically refers to construction products or to buildings, particularly in the field of research for energy-efficient buildings. In order to simplify access to relevant guidance of for practitioners, the EeBGuide project yielded two separate documents: one for building products, and one for buildings. Some elements are common to the two documents, but others differ, owing to the different scope.

1     Introduction

• 1.1    Energy-efficient buildings in Europe.
• 1.2    Basic information about this guidance document
• 1.2.1    Goal of this guidance.
• 1.2.2    Scope of this guidance.
• 1.2.3    Primary audience for EeBGuide.
• 1.2.4    Secondary audience for EeBGuide.
• 1.3    Life cycle analysis in the construction sector
• 1.3.1    Previous European projects on LCA of buildings
• 1.3.2    European standardization works on LCA of buildings
• 1.3.3    LCA studies within research projects of the Energy-Efficient Building European Initiative (E2B EI)
• 1.4    EeBGuide within the European context 

This guidance is focused on LCA studies of buildings and building products within the framework of the Energy-Efficient Building European Initiative (E2B EI), which creates technologies for an energy-efficient Europe. LCA assesses the environmental loads and performance of these new products and technologies, demonstrated mainly within building applications. LCA is used within European research projects on matters of energy efficiency in the construction sector that are managed under the E2B EI umbrella. The main aim of this guidance is to provide rules and instructions on how to conduct LCA studies consistently within such research projects.

A variety of questions, aspects and topics often arise during such an LCA study, but the answers in the literature and standards are often not coherent, or sufficiently extensive. The key objective of this guide is therefore to provide information on definitions, calculation rules, assumptions and comparative results of LCA studies for energy-efficient buildings and building products with regard to such aspects.

The guidance is based on existing ISO standards on LCA [ISO 14040-44], European standards [EN 15804] and [EN 15978] with regard to LCA, and other reference documents [ILCD 2010a], [ILCD 2010b], [ILCD 2010c], as well as on current discussion topics within the LCA construction community. It brings this information together in one comprehensive guide. It also clarifies aspects that are not totally consistent or may even be contradictory in the various LCA-related standards and reference documents, as well as those aspects that are generally not specified.

There are two main approaches to LCA studies: attributional and consequential. Attributional LCA studies generally do not investigate the potential consequences of a product system for the background system or for other systems (the ILCD Handbook denotes this as decision context situation A). By contrast, consequential LCA studies do investigate those consequences (decision context situation B in the ILCD Handbook). In section G-02, guidance is given on how to identify the decision context of a study. In general, this guidance document is limited to the case of attributional LCA studies. This is consistent with CEN standards EN 15804 and EN 15978, which are limited solely to this case.

For consequential LCA studies, various scientific aspects are yet to be clarified, and a broad scientific consensus on the different aspects is yet to be reached. If a practitioner identifies the need to conduct a consequential LCA study, guidance can be found in the literature and in the ILCD Handbook.

1     Introduction

• 1.1    Energy-efficient buildings in Europe.
• 1.2    Basic information about this guidance document
• 1.2.1    Goal of this guidance.
• 1.2.2    Scope of this guidance.
• 1.2.3    Primary audience for EeBGuide.
• 1.2.4    Secondary audience for EeBGuide.
• 1.3    Life cycle analysis in the construction sector
• 1.3.1    Previous European projects on LCA of buildings
• 1.3.2    European standardization works on LCA of buildings
• 1.3.3    LCA studies within research projects of the Energy-Efficient Building European Initiative (E2B EI)
• 1.4    EeBGuide within the European context 

The EeBGuide is oriented mainly at LCA practitioners and/or building LCA tool developers. It is not an introduction for novice LCA users, as it assumes a basic knowledge of the standards [ISO 14040], [ISO 14044], the ILCD Handbook, and EN 15978 and EN 15804, as well as practical experience, although detailed knowledge of these is not required. However, it is assumed that the reader using this document has access to these sources (especially the ISO and CEN standards) as they are referred to, and need to be consulted in detail for some items.

The principal audience for this document is the LCA practitioner who is required to deliver an LCA study within a European research project, particularly those that fall under the EeB PPP framework (see 1.3.3). For this audience, the document contains the rules and guidance to produce the study in a generally agreed and consistent way. The goal of projects of the EeB PPP framework is to “deliver, implement and optimize building and district concepts that have the technical, economic and societal potential to drastically decrease energy consumption and reduce CO₂ emissions in both new and existing buildings across the European Union”. LCA plays a large role as a measuring instrument in these projects, but the main focus clearly lies on technical innovations. The target audience of the project outcomes is mainly researchers, companies, designers and consultants in the field of construction.

1     Introduction

• 1.1    Energy-efficient buildings in Europe.
• 1.2    Basic information about this guidance document
• 1.2.1    Goal of this guidance.
• 1.2.2    Scope of this guidance.
• 1.2.3    Primary audience for EeBGuide.
• 1.2.4    Secondary audience for EeBGuide.
• 1.3    Life cycle analysis in the construction sector
• 1.3.1    Previous European projects on LCA of buildings
• 1.3.2    European standardization works on LCA of buildings
• 1.3.3    LCA studies within research projects of the Energy-Efficient Building European Initiative (E2B EI)
• 1.4    EeBGuide within the European context 

Several European projects dealing with LCA and buildings have been conducted over the past few years. Most of them were aimed at adapting the methodological rules for LCA studies in the construction sector and enabling the development of user-friendly tools that can be used by building stakeholders, who are usually not LCA experts. These projects included, for example, REGENER, Annex 31 IEA, PRESCO, IMPRO-Building, ENSLIC Building and LoRe-LCA.

Two previous projects conducted under the Seventh Framework Programme (ENSLIC-Building and LoRe-LCA) may be seen as closely connected with the goals and scope of the EeBGuide project. These two projects have helped to define LCA methodology for the construction sector, and have identified needs for further research. Below are presented the citations from the projects’ websites.

“The ENSLIC project (ENergy Saving through promotion of Life Cycle assessment in buildings) promotes the use of life cycle assessment (LCA) techniques in design for new buildings and for refurbishment, in order to achieve an energy saving in the construction and operation of buildings. This action draw on the existing information generated from previous research projects regarding: design for low energy consumption, integrated planning, environmental performance evaluation of buildings, design for sustainability and LCA techniques applied to buildings. The output – compiled with the collaboration of key target groups – is a set of guidelines with a methodology which clarifies the various aspects of the LCA, e.g. purpose, benefits, requirements, flexibility and different techniques. This is applied to real buildings by a number of collaborating target groups. The results are disseminated to a wide target group through multiple channels and the potential for energy saving highlighted. Through this project tools for use in an integral planning process are being promoted to stakeholders who require a means to optimize environmental performance of buildings in a truly sustainable way.” [ENSLIC 2011]

“LoRe-LCA (“Low Resource consumption buildings and constructions by use of LCA in design and decision making”) aims to coordinate activities regarding the application of LCA in the European construction sector, focusing on comparing and improving the functional units used for LCA for whole buildings, improving the possibilities to compare results for different alternatives during design stage, and for comparison of results for different buildings. The project focuses on harmonisation and use of LCA-methods in design and decision-making for reaching overall goals of reduced resource consumption.” [LoRe-LCA 2011]

Another interesting initiative covering European countries and some others is the Sustainable Building Alliance (SBA). Officially created in 2008, the SBA is a collaboration between international research institutes, certification bodies and other actors in the building industry. The main research action of SBA aims at answering the need of the real estate and construction industry for the development and application of harmonized common metrics for assessing building performance, to be implemented in existing certification schemes. A draft Framework for Common Metrics was elaborated in 2009 and 2010 by a core group of SBA members. It covered six main impacts, which included four environmental indicators based on LCA methodology: these deal with energy, water, greenhouse gases (GHG) and waste. The next step was to ensure the operational feasibility and comparability of LCA results for buildings, especially in terms of calculation rules, Environmental Product Declaration (EPD) databases, life cycle stages and considered contributors (i.e. all the factors that are considered in an LCA). This was done in 2011, when the availability and maturity of methods, data and tools were studied. The SBA Common Metrics Framework was pilot-tested on real buildings to analyse its applicability, and possible future integration into existing certification rating schemes. This work has involved seven research and certification bodies in five European countries and in the USA. The working group highlighted the fact that the availability of homogeneous EPDs in each country is a crucial issue. The comparability of LCA environmental indicators is being tested in 2012 through a modelling study in each country, based on a single building design.

In these previous projects, no comprehensive guidance was given in a structured way according to the LCA steps as defined in ISO 14040 and the life cycle stages of the new European standards from CEN TC 350.

1     Introduction

• 1.1    Energy-efficient buildings in Europe.
• 1.2    Basic information about this guidance document
• 1.2.1    Goal of this guidance.
• 1.2.2    Scope of this guidance.
• 1.2.3    Primary audience for EeBGuide.
• 1.2.4    Secondary audience for EeBGuide.
• 1.3    Life cycle analysis in the construction sector
• 1.3.1    Previous European projects on LCA of buildings
• 1.3.2    European standardization works on LCA of buildings
• 1.3.3    LCA studies within research projects of the Energy-Efficient Building European Initiative (E2B EI)
• 1.4    EeBGuide within the European context