Extoling the benefits of timber construction in overcoming both the industry’s long and short-term challenges are key to growing the market for wood building products. David Hopkins, Executive Director at Wood for Good, explains why its Build with Carbon campaign hits home the message for the industry and beyond.
The UK is facing a significant shortfall in homes and there’s ongoing pressure on the industry to ensure that new buildings are delivered quickly to meet ambitious targets while producing buildings that are up to scratch when it comes to long-term energy efficiency. In addition, the UN Climate Change Conference in Paris later this year will enforce targets for reductions of emissions in the UK. With the built environment the largest carbon emitter in the UK – there’s an additional impetus for the sector to be more sustainable.
It’s a concern that, when unveiling the new housing zones in March, the Chancellor made no reference to environmental sustainability and there’s a risk that sustainable construction could fall off the radar in an attempt to deliver homes quickly. The fact is, modern methods of timber construction mean speed, low cost and high environmental performance needn’t be mutually exclusive.
Obviously, many within the timber industry have recognised the merits of using the material in delivering new buildings for many years and this has to some degree been seen in sectors like housebuilding where offsite methods using timber have been on the rise. Pre-engineered timber products allow a building to be made weathertight and water resistant far quicker, allowing wiring and other interior work to be carried out almost immediately.
Offsite construction can lead to a reduction of build times by up to 14 weeks in some cases – at a time when there’s significant pressure to deliver new homes quickly, this can’t be ignored. Timber also differs from other materials when it comes to prefabrication – its high precision finish make for a higher quality end product. In addition, with the impending Energy Performance Certification (EPC) rating deadline in April 2018, set to benchmark how commercially viable a building is, timber’s inherent energy efficiency is becoming increasingly valuable. With any building lower than grade D on the EPC scale, from A-F, no longer allowed to be rented, using wood products provides a cost-effective and natural way of incorporating this at source.
Despite this, the majority of UK housing continues to be delivered through carbon-intensive building methods and the built environment remains the nation’s largest emitter of CO2. Communicating the wider environmental benefits without hard data to back it up has limited a widespread drive by the construction industry to make wood the primary building material of choice.
Our ‘Build With Carbon: Don’t Emit It!’ campaign aimed to change this. We harnessed LCA information to put forward a case for wood over a series of three animations and we were able to show the level of carbon stored at each stage of the supply chain – from growth through to construction.
The first video showed that, over the course of 40 years, a typical tree in the UK will have sequestered 742 kg of CO2, the second scaled this up to a hectare of forest – 483 tonnes of CO2. The third looked at new homes as CO2 stores – with one home storing 19 tonnes.
Our aim was to demonstrate that developers would be essentially building with blocks of carbon – turning this into an appreciating asset, ie the property, rather a harmful gas in the atmosphere. This allowed us to show that if annual housing targets were met – 200,000 new homes delivered each year – the UK could store nearly 4 million tonnes of CO2 every year.
The videos highlighted that using timber in long-life applications in the construction sector would mean that more trees will be planted, grown and harvested before the timber product reaches its end of life. This provides for an emissions reduction and storage mechanism – with more carbon emissions being added to the store in each harvesting and each new building.
The Balehaus project, the UK’s first commercially available straw eco homes created by ModCell, is a good example of this in action. The method used prefabricated glulam timber frame filled with straw under pressure with lime render to make an entirely natural and thick walling for the homes – resulting in a level of insulation that could reduce fuel bills by up to 90 per cent and 19 tonnes of carbon dioxide stored in the straw panels used.
Timber construction can be the solution to many of the challenges facing the delivery of new homes, it’s a preferred material for offsite construction – a method which can dramatically reduce build times, it has inherent thermal efficiency and it could see the UK capture and store a significant body of CO2 annually.
Communicating this to the sector and policy makers is key in driving up demand for timber products in the UK and therefore increased commercial forestry. This cyclical process of harvesting timber and planting more trees would then leading to a continual storage of CO2 by the built environment, a situation which could aid the UK in its drive to meet climate change targets.
As part of our work we’re keen for the entire industry to come forth with more case studies of timber meeting construction’s challenges of speed, energy efficiency and sustainability. The Build with Carbon campaign is a stepping stone to further campaigns which could see timber at the heart of a new era of sustainable construction while being the solution to delivering much needed homes up and down the country.
For more information on Wood for Good and to view the Build with Carbon video visit: www.woodforgood.com
