by Catherine Delahunty
The Ministry of Agriculture and Forestry released a fascinating new report today.
The research project, Environmental Impacts of Multi-Story Buildings Using Different Construction Materials, modelled the life cycle energy use and carbon dioxide (CO2) equivalent emissions of four similar office building designs that used different materials as their main structural element: concrete, steel, timber and ‘timber-plus’. The latter also used wood-based non-structural elements.
This new report is a very positive contribution in that it takes a life-cycle analysis approach to the environmental impact of construction materials. This sort of analysis is the science of the future.
The report’s conclusions around timber as the most environmentally sustainable material can only be strengthened by regulation that prevents the import of illegal and unsustainable timber from tropical forests.
Deforestation accounts for about 20% of the world’s carbon emissions, the largest single source. Much of that is a result of illegal and unsustainable logging, and New Zealand still imports timber and wood products of this deforestation.
Timber that is sourced by destroying rainforest cannot be considered environmentally friendly, and continuing to allow its import undermines sustainable forestry here and in developing companies.
Fortunately, the Government has an opportunity to find the best regulatory solutions through my recently-drawn Members’ Bill.
The Customs and Excise (Sustainable Forestry) Amendment Bill will have its first reading in September, and requires majority support to proceed to a select committee for consideration.
The other essential mechanism to ensure that the carbon values of timber are recognised in the economy is a price on carbon. Forests capture carbon, in contrast to the production of concrete and steel which emit carbon.
A price on that carbon through the Emissions Trading Scheme would incentivise the use of environmentally-friendly timber in building construction and create jobs in the foresty industry.