Does Part L 2013 spell death for renewables?

  • Email
  • Comments (7)
  • Save

A focus on building fabric instead of renewables is the most cost effective approach for housing, says Mel Starrs

By far, the most exciting aspect (if there can be said to be one) surrounding the Part L 2013 consultation is the Green Deal, consequential improvements and Part L1B. However, for the new build housing sector there is still quite a bit to get to grips with, particularly for anyone in the private market who has yet to encounter FEE (fabric energy efficiency).

On first sight, the headline figure of an 8% carbon improvement over 2010 levels for the government’s preferred route may not sound particularly taxing, but there is a quantum shift in focus towards a fabric first approach.

There will be a shift in capital spend in housing away from renewables towards fabric, with a concurrent up-skilling of the industry

The drivers for this are, typically for the times we live in, economic. Renewables, while effective at reducing carbon, are too expensive for housing in these straitened times, as demonstrated by the impact assessment which accompanies the consultation documentation. Rather than setting a 25% target that would render many housing developments uneconomic, DCLG are pushing the fabric to close to the limits of diminishing returns. This is a significant step towards zero carbon.

Fabric first is a mantra the industry has been trying to follow for years, which makes sense given one would hope the fabric is generally around for the equivalent of several lifetimes of technologies. So why have we not been able to follow a purely fabric first approach up to now? The tension between fabric and renewables in recent years has been driven by concurrently trying to meet the parallel, but often contradictory requirements of both the planning and building regulations systems.

‘Merton’-style planning requirements, which incorporate the requirements of Planning Policy Statement 22 (PPS22) to use on-site renewable to deliver 10% or 20% energy or carbon reductions, have been competing with the needs of meeting Part L 2006 or 2010. Part L was left flexible enough to allow a balance of renewables and fabric and whereas the most cost effective approach may have been fabric first, the renewables targets typically ‘won’ a chunk of the capital cost. Fabric would typically be designed up to that point where adding the required renewables percentage met the target for compliance with building regulations. The renewables contributed to local, regional and national targets and to the overall goal of reducing carbon by 80% by 2050.

Concentrating on fabric should also begin to alleviate one of the factors in the design-performance gap

The move towards a fabric first approach in Part L 2013 is set in the context of the long awaited National Planning Policy Framework (NPPF). As of 1 April 2012 PPS22 will no longer be current and local plans which have been developed with ‘Merton’-style rules will have to prove the viability of such approaches.

The proposed standards are buildable today – we are seeing some schemes, especially mid-rise apartment blocks in London where Greater London Authority (GLA) have been demanding compliance to Part L 2010 through energy efficiency alone, meeting and exceeding these targets already.  

What will this mean in practice? Adherence to the fabric performance holy trinity of increased U-values, attention to thermal bridging and increased air tightness. There will be a shift in capital spend in housing away from renewables towards fabric, with a concurrent up-skilling of the industry, as we endeavour to build the most efficient dwellings we possibly can. Concentrating on fabric should also begin to alleviate one of the factors in the design-performance gap.

It’s not all doom for the renewables sector though - the accompanying preferred route for Part L2A for non-domestic building of 20% finds renewables are a more cost effective route than fabric for this very broad sector.  Presumably this is due to typically larger volume to surface area ratios, where we meet the point of diminishing returns on fabric earlier.

Mel Starrs is associate director at PRP Architects


Readers' comments (7)

  • At some point we are going to have to address the inherent conflicts between planning and conservation policies and the energy efficiency of the existing housing stock.

    Unsuitable or offensive? Report this comment

  • Meanwhile, out in the world that most people live in, we have government ministers on the one hand taxing motor traffic to get people onto public transport, then allowing inflation busting rises in the cost of it!

    Unsuitable or offensive? Report this comment

  • Building "sustainable" houses is not sustainable if their inhabitants rely on cars to get to and from them. You can fiddle with cold bridges and high U-values for the fabric as much as you want to, but if Mr. Bloggs is driving to the railway station and Mrs. Bloggs s chauffeuring her children to and from school before driving to Sainsbury's and back, it's all completely pointless.

    In other words, sustainability is not for building construction nerds, it's for strategies about planning and the kind of cities we should be building for the future.

    Unsuitable or offensive? Report this comment

  • zecks_marquise

    I agree with sceptical, but the problem is that the only way to reduce the need for cars is higher density living. With the possible exception of Nine Elms, I struggle to think of a genuine effort by planners to ramp up density in an area that people actually want to live.

    Unsuitable or offensive? Report this comment

  • That's what needs to happen- we need to work our way back to compact cities in which most people will not need to own a car and will only use one occasionally.

    But this will require legislative action and at the moment I see no sign ot that happening. In this situation, asking architects to "design for sustainability" is a bit of a sick joke.

    Unsuitable or offensive? Report this comment

  • Higher densities is not the answer it was tried in the 1960s with appalling results - this will only work in very few city centre locations. The answer is de-centralisation of services - local shops smaller hospitals, smaller schools, local police stations etc. In other words a complete reversal of government policy of the last 30 years

    Unsuitable or offensive? Report this comment

  • Jonathan I totally agree....de-centralisation is the way forward. Taking a quick stroll to the local Green Grocer and the Local Butcher would benefit everyone. www.reork.com

    Unsuitable or offensive? Report this comment

Have your say

You must sign in to make a comment

sign in register
  • Email
  • Comments (7)
  • Save