Retrofitting old railway arches could produce 50% less carbon compared to building new industrial space


Retrofitting old railway arches can reduce carbon emissions by 50% compared to building new industrial space, according to a new study carried out by sustainability consultants Engineering Services Consultancy (ESC).

We commissioned ESC to evaluate the environmental impact of creating commercial space in railway arches, versus a new build development. The study found that creating light industrial space in a typical derelict railway arch was found to have an embodied carbon level – the emissions during the construction of a building rather than when it is in use – of around 148 kgCO2e/m2, significantly lower than the range of 300-700 kgCO2e/m2 for comparative new build developments.

The report found that the embodied carbon generated from retrofitting is significantly lower. The majority of embodied carbon originated from the use of concrete in the floor of the refurbished arches, as well as the wall and roof lining needed to make them waterproof. This is because the brick viaducts that provide the external walls and roof were built in the mid-19th century, and remain largely unchanged since then.

Engineering Services Consultancy Director Vicki Wilson BSc(Hons) DipSBP CEnv MIEMA, said:

“This report has evaluated the carbon in construction (embodied carbon) levels of a typical railway arch. We concluded that arches have significantly lower embodied carbon levels than a new build equivalent for a light industrial space. By creating more spaces with reduced carbon impact, it will give businesses a positive step in their journey to achieving Net Zero Carbon.”

The Arch Company CEO Craig McWilliam, said:

“More retrofit is the future if our industry is to meaningfully reduce its carbon output. Measuring the embodied carbon of a building, as well as its operational carbon, should lead to more reuse and recycle instead of building from new.

“The railway arches are one of the biggest reuse and recycle projects in commercial property. By 2030, under our Project 1000 development plan, we will have invested £200m to bring a thousand empty and derelict spaces into use. This will create productive space for a thousand businesses with much less carbon than a newly built space.”

The Arch Company purchased 5,200 railway arches from Network Rail in 2019. Approximately 3,800 of these arches were occupied, predominantly by small businesses, with 1,400 derelict or empty. We saw the incredible opportunity this offers and committed to bringing a thousand of these spaces into use by 2030 as part of our £200m development plan, Project 1000. Schemes in London, Bristol, Wigan, Manchester, Windsor and Newcastle are already underway – please visit the Project 1000 webpage to read more about our projects.