Why it’s a myth that sustainable buildings cost more

COMMENT The government’s ambitions to achieve net zero greenhouse gas emissions by 2050 are starting to be taken seriously by the property industry. New buildings will have to be delivered with ultra-low energy consumption and net zero carbon performance in mind, and existing buildings will need to be improved through retrofitting to closely match this performance. The need for sustainable, low-energy development will increasingly be driven by ESG investment, evolving national and local regulatory environments and, importantly, consumer demand. Funders have been concerned about sustainability for some time and high ratings in sustainability assessments such as BREAAM and LEED have long been stipulated in project briefs. There is, however, increasing focus on low-energy and low-carbon performance as organisations seek to decarbonise their own operations and property. Shifting investment priorities Mindful of what an environmentally inefficient portfolio can do to a corporate reputation, never mind its investment returns, investors will look to reduce their exposure to underperforming buildings and increase investment in future-proofing buildings with high environmental standards. The importance of this shift in investment priorities should not be underestimated. It is all the more obvious when high street retail banks are already offering preferential domestic mortgage rates to EPC A/B rated homes through new “green” mortgages. Closer to the coalface, it is important to stress that the biggest reductions in the impact a new building has on the environment are made very early on in the design process. Making sure that low-energy design or net-zero carbon targets are in the brief at the outset of a project can only help reduce costs. It is a myth that sustainable buildings have to cost more. The important thing is to consider such plans early on. An approach that adds cost to such projects is failing to think about environmentally sustainable design early enough. Trying to apply a fix onto a building that intrinsically consumes more energy is an expensive and, frankly, needless option. The trick is to design with sustainability and low energy consumption in mind. Always. Form factor is crucial When designing an energy-efficient building, it is important to consider its form factor: the ratio of external facade to the floor area. The lower the form factor, the more thermally efficient the building. Such buildings tend to be simpler with less articulation, and can be cheaper to build than a more complex building. An efficient form factor can help minimise the need for additional low energy measures; for example, insulation thickness may remain at more conventional dimensions, while still achieving a low overall heat loss. Good airtightness, a significant factor in a building’s thermal efficiency, is also simpler to achieve in a building with a rationalised external envelope. Developers and building owners need to be conscious of the end performance of their “product” and should care about how tenants will fit out and operate their buildings. To demonstrate effective environmental stewardship, property owners will increasingly report on the carbon emissions of their own building portfolios in company returns. Property owners leading the field in this area will need to engage with their tenants to help ensure that they are interacting with the buildings efficiently and that the tenants themselves are taking steps to reduce their own energy consumption. Owners will also need to invest in their existing portfolios to ensure low energy and carbon performance is achieved across their whole estate. Looking ahead, the next decade is becoming clearer in terms of legislation. But, beyond 2030, much will depend on how various decarbonisation strategies are progressing. Changes in the building regulations are being consulted on and the update to the domestic Part L 2021 has been set out and is to become mandatory over the next year. Part L updates and other national regulation updates will lead to greater improvements in building performance across the UK. The current updates will be stretching for many but will also act as stepping stones towards the performance requirements of the future. The UK is to be net zero carbon by 2050 (2045 in Scotland), and to decarbonise our whole economy all sectors need to decarbonise. Our buildings, however, have the biggest part to play in this process and we need to be setting them up now for a net zero carbon future. Andrew Leiper is net zero carbon leader and principal engineer at Max Fordham Photo: Max Fordham