Council's timber construction bias is misguided

Hackney Council’s move to create a ‘presumption in favour’ of using timber construction as reported in Building is misguided believes MPA - The Concrete Centre. The Centre advocates that, as each project is different, there should be no pre-determined design presumptions which could prevent the most appropriate material from being specified for the job.
 
Hackney Council has announced that it is actively considering ‘detailed management policies’ to promote timber through the planning system believing that this is in line in the government’s National Planning Policy Framework (NPFF) which has an emphasis on sustainable development. 
 
The Council’s premise seems to be largely based upon a misguided belief that the CO₂ impact of timber is much lower than other materials. “The timber industry can be very selective when it comes to presenting the environmental performance of timber construction”, said Andrew Minson Executive Director at MPA The Concrete Centre. “The press release incorrectly suggests that timber is carbon negative, which in whole life terms is simply not the case. TRADA’s own research using the PAS 2050 assessment of GHG emissions shows that the CO₂ in timber construction has a significant environmental impact over its life cycle. Their report entitled Timber Carbon Footprints (2009) shows that over a 100 year life cycle, the CO₂ footprint of UK timber frame construction varies between 400 and 980 kg CO₂ per tonne for Swedish timber. In contrast, concrete only contains around 40 – 140kg of embodied CO₂ per tonne of concrete when cement replacement is used.  Obviously concrete is heavier than timber, so design professionals will take account of this alongside the higher embodied CO₂ of timber.
 
Other performance issues that are often not fully accounted for include the CO₂ impact of transporting timber, most of which comes from overseas. Also, the impact of additional materials required for fire proofing and sound insulation tend to be overlooked, as is the increased risk of summertime overheating in lightweight timber frame homes. 

In addition there are the residents to consider. Problems with vibration and noise transfer between apartments has meant that house builder Bellway has recently announced that it does not intend to use timber-frame construction for future projects. The announcement follows complaints from residents of the housebuilder’s six-storey Keyse development in Bermondsey, London.  Residents have spent the last nine months complaining about vibration and noise and are warning that they may launch collective legal action.
 
“It is not enough to just cherry pick sustainability benefits”, said Minson. “The total whole life sustainability of a construction material must be considered, both embodied and long-term operational – which is where the vast majority of a building’s CO₂ impact lies. Furthermore, a presumptive bias at planning stage means that the benefits of each construction material are not being fully considered nor the decision made by the appropriate design professionals.”