img(height="1" width="1" style="display:none" src="")

How many dinners is that building worth? Free carbon calculator for industry works for lay readers too

Stephen Cousins

What started as in-house software at Elliott Wood has become a free, simple-to-use embodied carbon calculator aimed at resource-stretched practices

The Structural Carbon Tool aims to help designers and engineers make more climate friendly choices in their work.
The Structural Carbon Tool aims to help designers and engineers make more climate friendly choices in their work.

An engineer-developed embodied carbon calculator is being offered free to built environment professionals in a bid to tackle climate breakdown on a much bigger scale.

London-based structural engineer Elliott Wood partnered with the Institution of Structural Engineers (IStructE) to create the Structural Carbon Tool, Excel-based software designed to quickly estimate embodied carbon in a structure and compare up to six options at once.

Based on the principles set out in the IStructE publication ‘How to calculate embodied carbon’, the software aligns with relevant British Standards and the SCORS rating system, developed by the Institution’s Climate Emergency Task Group, is also includes RIBA and LETI benchmarks.

A key objective is to simplify the embodied carbon calculation process for smaller engineering firms who may be unfamiliar with the concept or lack the time or the tools to make accurate measurements.

Penny Gowler, associate director at Elliot Wood, said: ‘Parametric tools are available that run through structural options and estimate related embodied carbon, but we wanted to provide something that would enable a smaller company to design a project the way they are accustomed to, but with a small additional step to calculate quantities and compare different schemes to make better decisions. There’s currently nothing else like it available in a simple-to-use spreadsheet-type format.’

The Structural Carbon Tool started life in 2016 as in-house software used by Elliott Wood to improve the sustainability of its projects. Developed over the years, the latest incarnation came about after the studio approached the IStructE to create something that could reach a much wider demographic

There’s currently nothing else like it available in a simple-to-use spreadsheet-type format

The tool enables the user to estimate the amount of carbon in different parts of the design; identify carbon hotspots and opportunities to target material reductions; understand rough differences between different structural options; and communicate effects with the design team.

Through a simple interface they select materials such as concrete, masonry, or steel, from a drop down menu and input basic data on things like mass / volume of material, or the choice of concrete mix etc. A ‘custom EPD’ (Environmental Product Declaration) tab offers the option to input alternative materials and related data not included in the tool.

Accurate calculations of embodied carbon are converted into measurements more tangible and understandable to a lay person, such as the equivalent number of flights from London to New York, or the equivalent number of vegan meals.

‘When you talk about saving 5,000 tons of carbon it’s quite abstract and hard to grasp, we wanted to turn that into things that people might have a better feel for, we found this really useful when talking to clients and putting it into reports,’ Gowler concludes.

Structural materials are responsible for over 10% of CO2 emissions worldwide.

Free-to-use embodied carbon calculators have also been developed by Hawkins\Brown and FCB Studios, the latter being developed to use AI. Software giants are also working in this area with EC3


Embodied carbon and how best to use limited resources took centre stage at the RIBA’s most recent Smart Practice conference

How can we break our addictions to fossil fuels, waste and consumption?

Strengthening the 18th century, timber-framed Corn Exchange and connecting it to an upgraded 1930s Studio Theatre were key to opening the arts centre to modern audiences

How FCBStudios and Max Fordham refurbished the listed Corn Exchange and Studio Theatre

Western modernism came to colonial West Africa and India, but with independence they made it their own. Tropical Modernism: Architecture and Independence follows the story

Locals made ‘progressive, optimistic’ style their own

Bid to be one of six to join a new four-year Somerset and Wiltshire framework, revitalise an historic East of England city centre or help tell the tale of Cornwall. These are some of the latest architecture contracts and competitions from across the industry

Latest: £6m West Country architectural services agreement

Will Burges’ self-build family home in suburban south London is inhabited and looks finished, but this flexible, future-looking house is intended to be a work in progress

It looks complete, but Will Burges’ house is intended never to be truly finished