The Life Cycle Analysis and Assessment (LCA) is a quantitative analysis of the environmental impacts of a product, e.g. construction materials. Comparing the environmental merits of building materials should take into account the environmental impact at all stages of a product’s life cycle, "from the cradle to the grave", that is from extraction to final disposal. LCA measures the inputs and outputs to the whole process to find out what is released to the environment. For the analysis, lifecycle stages are divided into

• Resource base and extraction
• Transportation
• Processing
• Installation, In-life use and maintenance
• Disposal

Analysing all those stages – from the planting of a tree, its felling, transport, etc. to the disposal or reuse of timber - and comparing the sum of its impacts with other construction materials, reveals the most positive characteristics of timber for modern construction.

For example,

The product energy requirement, in kilowatt hours, is 8 times higher for a PVC-U window compared to a timber window

The manufacture of steel components uses 4,000 times more energy than its timber equivalent

Concrete creates 5 times as much solid waste

The thermal resistivity of wood is - 8 x better than concrete - 413 x better than steel and - 2,000 x better than aluminium

For more detailed information, please have a look at the following research reports:

ATHENA Sustainable Materials Institute: Product Life Cycle Inventory Studies

Building Research Establishment BRE: Environmental Profiles

Building Research Establishment BRE: Environmental profile of a timber frame house an initial study

European Forest Institute: Life-Cycle Analysis a challenge for forestry and forest industry