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Environment

The basis for most environmental assessments, environmental legislation and private schemes are life cycle thinking and life cycle assessments (UNEP, 2009). This chapter will introduce you to life cycle assessments, the methodology for assessing sustainability of buildings, and assessments of buildings and construction products. It will also provide an overview of the most important environmental legislation in the EU, with emphasis on chemicals.

6.1 Life Cycle Assessments

A life cycle assessment (LCA) is an assessment of a given product´s global, regional and local environmental impacts and consumption of resources throughout its whole lifetime. 

6.1.1 LCA

An LCA consists of various stages, as shown in figure 6.1.

  • The extraction and production of the raw materials.
  • The manufacture of the product.
  • The use of the product (e.g. the energyconsumed whilst used by the customer).
  • The End-of-Life (EOL) of the product. It can either be landfilled, energy recovered or recycled.
  • Between the various stages is the transport of the raw materials, the finished product, and the used product on its way to EOL.
Life cycle of a product

Figure 6.1.1 Life cycle assessment (LCA)

Figure 6.1.1 shows the life cycle of a product from the extraction of raw materials, to the manufacture of the product, the use phase, and the EOL, which is divided into landfill, recycling, and energy recovery. Transport is incorporated in all the life cycle stages.


Environmental impacts are divided into global (effects on a global scale), regional (effects on a regional scale), local impacts (effects on a local scale) and resource and energy consumptions Local impacts are not dealt with further in this book.

Global environmental impacts

Global environmental impacts comprise two parameters:

  • Global warming (emissions – e.g. CO2)
  • Ozone Depletion (emissions of CFC gases)

Regional environmental impacts

Regional environmental impacts comprise three parameters:

  • Acid lakes, acid rain (acidification of soil and water)
  • Algal blooms (eutrophication)
  • Summer smog (photochemical ozone creation)

Resource and energy consumptions

In an LCA, two types of consumptions are assessed; use of abiotic resources like metals (materials) and use of fossil energy.

  • Consumption of primary resources (depletion of abiotic resources – elements)
  • Consumption of fossil fuels (depletion of abiotic resources – fossil fuels)

6.1.2 Other parameters of life cycle assessments

Carbon footprint

A carbon footprint is a subset of a full LCA, where only greenhouse gas emissions (e.g. CO2) are evaluated.

 

Cradle-to-gate

Cradle-to-gate is an assessment of a given product in which only the extraction of the raw materials (cradle), transport and production are included.

Cradle-to-grave

A cradle-to-grave assessment consists of a full life cycle assessment. It thus includes extraction of raw materials, manufacture of the product, use of the product and EOL.

Cradle-to-cradle

Cradle-to-cradle is almost the same as cradle-to-grave but with a different approach to EOL. The approach is that all materials should always be recycled into new products. Hence chemicals should be used with great care in order to prevent discharge to the environment. In cradle-to-cradle, energy consumption is not taken into account because it is presumed that all energy is renewable (ECO platform, 2014).

ECO platform (2014) http://www.eco-platform.org/ (accessed: 2014-11-07)
UNEP (2009) United Nations Environmental Programme Life Cycle Management How business uses it to decrease footprint, create opportunities and make value chains more sustainable.