The environmental benefits of using timber for large-scale commercial buildings have been highlighted in a report from the Ministry of Agriculture and Forestry.
The report compared the energy use over the entire life cycle of four similar office building designs constructed using concrete, steel, timber and what is known as "timber plus", which uses wood for the building's bones and its fittings.
Of the four, timber-plus building had the lowest environmental impact, producing about 4,500 tonnes of carbon dioxide equivalent. Steel had the highest at almost 7,000 tonnes.
Ministry forest policy co-ordinator John Eyre says the results are based on a 60-year life span for each building.
He says this study made the four buildings as near identical as possible to ensure it was the effect of the building materials that was examined rather than other factors.