(by Dan Ridley-Ellis 14/05/2021)
The Environmental Audit Committee is launching an inquiry into the sustainability of the built environment. It will look at the best routes to net zero for our future building needs from low carbon materials through to policies to minimise the whole life carbon impact of new buildings. The Committee is inviting written submissions (deadline 15 May, 22:59).
Here is my own personal view – which you may or may not agree with. I’m sharing it in case it encourages you to submit a response of your own.
Call for evidence – Sustainability of the built environment.
Written evidence submitted by Dan Ridley-Ellis, Edinburgh Napier University (as an individual).
The most important things are:
• Creation of a properly integrated land use policy that resolves counterproductive friction between agriculture, forestry, and other land uses.
• Reduce reliance on material imports, that only come from a limited number of countries, to avoid unaccounted for negative sustainability impacts that may well be worse than the perceived benefit in the UK.
• Concentrating on messaging, education, training and people’s behaviours since these have major impact on the actual sustainability outcomes.
• R&D, regulations and standards improvement to reduce pressure on future natural systems to provide our material needs. Strategic priority for what the (limited) natural systems are able to provide sustainably. To avoid the funding for R&D going only to novel approaches at the expense of funding for more straightforward research that could actually lead to better sustainability outcomes.
- I am an academic researcher at Edinburgh Napier University and head of the Centre for Wood Science and Technology (https://blogs.napier.ac.uk/cwst/). My work includes wood properties and timber grading for construction. I am involved in standardisation work related to this at national and European level and I lead the European CEN task group responsible for approving new structural timber grading.
- I am involved in projects researching timber for construction and work with growers, processors and importers of timber. I am not, myself, a sustainability specialist, but I have colleagues and research partners who are. One of the projects we are currently doing is InFutUReWood (https://www.infuturewood.info/) and I lead the work package that aims to provide a better route for structural timber from dismantled buildings to be reused in new construction.
To what extent have the Climate Change Committee’s recommendations on decarbonising the structural fabric of new homes been met?
- There is some early progress in addressing the skills gap with new investments in this area, but I expect this will continue to be a limiting factor. I do not yet see much progress in improving regulations and standards – which are not keeping up with need or with innovation.
How can materials be employed to reduce the carbon impact of new buildings, including efficient heating and cooling, and which materials are most effective at reducing embodied carbon?
- Some of the ways in which materials influence the carbon impact of buildings are commonly discussed, but some rarely are. I will focus my comments on the less discussed aspects:
- There are carbon impacts (and other environmental impacts) that arise from land use associated with raw material production. Some are direct and some are indirect. Where these happen in the UK these can be addressed through creation of a properly integrated land use policy that removes counterproductive friction between agriculture, forestry, and other land uses. Where this impact occurs in other countries this is more difficult to monitor, but it should, nevertheless, be better understood and discussed. This includes the potential unintended consequences of, for example, carbon offsetting projects abroad that displace the previous forest uses and require the local communities to turn to more problematic ways of generating income and satisfying their own material needs. Too simplistic a focus on carbon accounting can potentially create worse sustainability outcomes. In order to have some positive influence on what happens in other countries we need to reduce reliance on material imports, that only come from a limited number of countries.
- The embodied carbon and energy from manufacture and transport is commonly discussed, although it is not clear how to apportion ‘ownership’ of this for wood products or to properly account for this downstream (especially to incentivise circular economy and extended building lifetime). There is also the danger that, if a material is viewed as being carbon negative, then there is a reduced incentive to use it efficiently, and even the incorrect notion that the more of it that is used in a single building the better it is.
- The material impact on energy efficiency of buildings is also commonly discussed, but less commonly discussed are the impacts of maintenance and occupant behaviour.
- The material aspects of building adaptability, flexibility and repair are vital considerations but are only recently being discussed.
- Significant progress has been made in recycling at end of building life, especially for wood waste, but the level of reuse needs to be improved. This does, however, seem not to be widely known and there is still perception of large amounts of wood waste going to landfill, and a lack of appreciation of the kinds of materials that can be made from wood waste.
- Part of the overspecification problem is assumption that (perceived) ‘quality’ materials will last longer when in fact it is people’s behaviours that tend to shorten the life of materials and buildings. There is also a danger that the discussion around materials misses the affordability angle because of this assumption that (perceived) ‘quality’ leads to sustainability. Further, the undeserved description of some materials as being ‘low quality’, ‘disposable’ and ‘destined for landfill’ risks creating that very problem. Two particular examples are the very common descriptions of UK grown timber, and of the board products produced from forest thinnings, sawmill co-product, and recycled wood.
What role can nature-based materials can play in achieving the Government’s net zero ambition?
- Biotic materials are an essential part of achieving the net zero ambition, although there is not yet a common agreement on what “nature-based” would mean (plantation forestry of non-native species for timber production being regarded by some as not ‘natural’ for example). This current lack of consensus is one of the reasons why a properly integrated land use policy is required.
- But biotic materials (and afforestation) can only be a part of the solution, and not be seen as a fix for unsustainable behaviours and resource uses.
- Additionally, there seems to be no overall understanding for the limits of nature based systems to provide all the things they have potential for – in the short or long term. There needs to some strategic priority since there is not enough for everything. There also needs to be more focus on extended life, reuse, and recycling of ‘renewable’ materials, since they are only ‘renewable’ to a certain extent.
What role can the planning system, permitted development and building regulations play in delivering a sustainable built environment? How can these policies incentivise developers to use low carbon materials and sustainable design?
- Some countries seem to have had some success with a wood first policy, although I would put retrain and renew first. We need a planning system that encourages design for reuse, disassembly and flexibility.
- Work is need to make building regulations and construction product standards more compatible with reuse.
- Standard floor (live) design loads could be reassessed since they are a potentially unnecessary cause of sustainability and material scarcity for buildings.
- Habitual over-specification should be discouraged through better messaging, education and training.
- Research should be incentivised to enable use, in construction, of a wider range of home grown timber, from forests not managed primarily for timber. This should be linked to wider forest policy and timber availability forecasts. Research funding is commonly allocated based on novelty and research quality, but sustainability and strategic impact should be a factor. Funding for R&D going only to novel approaches should not be at the expense of funding for more straightforward research that could actually lead to better sustainability outcomes. Further, as Baroness Young stated in the April 2021 APPG meeting on forestry and tree planting, we need to be absolutely clear about the things we want to achieve through multi-purpose forestry so that “we do not find one or other of the competing interests is getting the upper hand, because then we all start getting back in the bunker again”. https://youtu.be/32NRq7CjX70?t=2632
What methods account for embodied carbon in buildings and how can this be consistently applied across the sector?
- Carbon accounting for wood is less about the methods, and more about the decisions of the boundaries. This is other reason why an integrated land use policy is required.
- Embodied carbon is only part of the picture, and there needs also to be a material scarcity factor.
Should the embodied carbon impact of alternative building materials take into account the carbon cost of manufacture and delivery to site, enabling customers to assess the relative impact of imported versus domestically sourced materials?
- Probably yes, if it can actually be done, but the land use impact is the bigger thing missing.
- I will note that “imported” vs “domestic” is too simplistic a view since for some locations, imports come from much shorter distances than domestic sources or via transport modes with less impact.
How well is green infrastructure being incorporated into building design and developments to achieve climate resilience and other benefits?
- This seems to be in a very bad situation at present. Urban trees are not properly valued, and even when investment is made in planting them they are often not properly maintained. Proper practices for working around them are frequently not respected causing (sometimes fatal) damage to the trees, and this is definitely one aspect that is missing from the education and training of most building professionals.
- If there is some green space at development stage this is often quickly removed by residents to make way for vehicle parking, so measures to reduce the need for private vehicles are important here.
How should we take into account the use of materials to minimise carbon footprint, such as use of water harvesting from the roof, grey water circulation, porous surfaces for hardstanding, energy generation systems such as solar panels?
How should re-use and refurbishment of buildings be balanced with new developments?
- Re-use and refurbishment should be the higher priority, but these need to be suitable dwellings for the housing need – not investments for landlords. The more fundamental problem is people’s behaviours, and in satisfying housing needs. Buildings that are valued as homes first and foremost will be the ones that last the longest.
What can the Government do to incentivise more repair, maintenance and retrofit of existing buildings?
- Make it easier to satisfy the regulations for such buildings
- Invest in R&D to make it achievable for more buildings
- Wider policy that supports people living and working in the areas with existing buildings that could be improved rather than demolished or neglected
- Tax incentives (including VAT)