What professionals in the engineered timber industry need to keep on their radar

From cradle to gate

With MBIE’s carbon regulations on the horizon, here’s what professionals in the engineered timber industry need to keep on their radar.

New Zealand is on the path to a low emission, climate resilient future – this means targeting sectors with a larger carbon footprint to try and reduce emissions. The New Zealand Government has committed to being carbon zero by 2050, and that means all government departments are looking at how their sector can contribute. The Ministry of Business, Innovation and Employment (MBIE) has already started consultation on how to ensure new buildings are energy efficient and low carbon. Our built environment is responsible for 20 percent of the country’s carbon footprint, according to the New Zealand Green Building Council, with emissions from the industry at large increasing by 66 percent in the decade from 2007 to 2017. MBIE is proposing the building industry initially counts the carbon in new buildings. From there, companies will move to stay under a cap – a maximum amount of carbon – which will be set in the Building Act. Feedback from the first round of consultation endorsed this approach. As residential buildings use predominantly timber frames, the industry expects to see steel frame, steel beams and masonry phased out at a steady pace in favour of timber. The big shift builders and contractors will see more and more timber specified in medium to large buildings – that means engineered wood. You will see a mix of NZ grown and manufactured LVL, Glulam and CLT, plus familiar timber sheet materials, displacing the high carbon materials specified in the past. Many WPMA members have produced EPDs – environmental product declarations – for designers to use when working out the carbon footprint of individual materials and building as a whole. The EPD data includes forestry operations, harvesting, sawing, drying and the further processing operations for each product type as required, such as drying, surfacing, fingerjointing and face gluing. WPMA’s next step is to get its Timber Design Centre, a timber advisory service in partnership with the New Zealand government, up and running to accelerate design innovation and provide a solid resource for builders and contractors’ pricing and building for large scale engineered wood products.

As residential buildings use predominantly timber frames, the industry expects to see steel frame, steel beams and masonry phased out at a steady pace in favour of timber.

Beyond its carbon credentials, timber is a gorgeous material that lends itself to captivating, large-scale buildings. From the local pine showcased in the Nelson Airport Terminal to the award-winning Te Pa Tauira | Otago Polytechnic Student Village, timber structures create warm, inviting spaces that aren’t easy to forget. There are some big shifts ahead of us as we rise to the challenge of achieving carbon zero by 2050. Fortunately, we have plenty of homegrown timber, as well as NZ wood processors and manufacturers producing the products we need to meet the challenge. The industry can make a huge impact just by doing our bit to rein in climate change and creating beautiful buildings at the same time. CT

WPMA PO Box 3551 Wellington (04) 473 9220 www.wpma.org.nz

— Advertising Feature Timber’s strength also lies in its sustainability Engineered timber’s load bearing abilities and structural strength make it an ideal building material. It is not only highly competitive with steel, but it is also a renewable, sustainable product, which places few demands on the environment during the construction process. To be considered sustainable a product must not be harmful to the environment or deplete natural resources, and must be able to be maintained for a long time. Being timber, engineered timber products meet these requirements because of photosynthesis. Photosynthesis is how trees combine carbon dioxide and water to form glucose and the structure of trees. Glucose is converted into cellulose which makes up the fibres or cells of the tree. From a sustainability point of view, the important thing here is that the formation of timber actually removes CO2 from the air. This helps to reduce the amount of CO2 in the air which many scientists believe is contributing to climate change. One kg of wood contains just under half a kg of carbon. A house which contains 20 m3 (9 tonnes) of wood would therefore have removed 4.5 tonnes of carbon, or around 16.5 tonnes of CO2 from the atmosphere. Given that a litre of petroleum when burned in a car engine produces around 2.5 kg of CO2, and an average car burns about one litre per 10 km, a little bit of arithmetic shows that your average house will store in its framing the CO2 generated by driving over 70,000 km. So timber is sustainable because the carbon stored in timber is actually lessening the probability of drastic climate change.