The cost of Part L
The demands of compliance with the new Part L regulations could result in additional costs in the short term creating a challenge for architects with demanding clients.
Long awaited changes to Part L have coincided with the trough of the property market and the start of government spending cuts. Although there are signs of recovery in the prime commercial and residential markets of London, most development markets are still subject to significant viability and funding challenges.
The significant performance improvements required by Part L 2010 will introduce a cost penalty that will vary in accordance with building type and design strategy. Although construction costs are significantly down on their 2008 peak – typically by 20% or more – viability remains a challenge. Regrettably, in the short term, improved carbon performance could be perceived as an additional cost driver rather than as a long-term source of value.
Despite this gloomy prognosis, there are clear signs in the London commercial market that occupiers want high performance, low carbon buildings. The challenge for architects is to work creatively within the regulations to deliver the best balance between performance, aesthetics capital and operational cost.
Depending on the extent and specification of glazing, and the range of solar gain and emissions reduction technologies adopted, the Part L cost premium for a high quality commercial office could range from 2 to 9%. Low cost options typically involve less glazing - so architects will need to be innovative in delivering attractive and effective workspace under the new regulations.
Requirements for residential schemes are more straightforward than the aggregate approach adopted under Part L2A. Thanks to the Code for Sustainable Homes, there is plenty of experience of meeting carbon reduction targets for residential. Again there are cost premiums – particularly if low-carbon technologies such as MHVR or PVs are used. Architects can contribute to the cost effective delivery of Part L by driving a genuinely holistic approach to low-carbon design. This should involve inputs from all of the supply chain, not only avoiding duplication of effort but also eliminating unnecessary heat gains/fabric losses that could be mitigated through effective detailing.
While markets remain unpredictable, we know that Part L will be revised again in 2013 and 2016. Clients and designers who develop a competitive advantage in the delivery of low-cost, low-carbon buildings will be well placed for success in these turbulent times.
Simon Rawlinson is head of Strategic Research and Insight at EC Harris