Calculating carbon

13 December 2021

James Latham’s new Carbon Calculator is a bold initiative designed to give full transparency on the carbon impact side of its products and aid the wider appreciation and specification of wood’s benefits. Stephen Powney talked to James Latham’s group head of marketing Stuart Devoil

The talk of carbon has had a high priority in the news of late thanks to the COP26 (UN Climate Change Conference of the Parties) taking place in early November.

Timber, of course, has a positive message in the carbon equation, with trees and wood products embodying carbon – a fact that is increasingly being appreciated by the architect and specifier community. Timber product companies are seeing the benefits in engaging in the debate too.

One of the largest and longest-established UK timber product distributors, James Latham, has used the background of COP26 to launch its own carbon initiative following a painstaking research project involving the BioComposites Centre at the University of Bangor.

“We’ve always been a very sustainably focused business and the environment is always at the forefront of what we do,” explained Stuart Devoil, Lathams’ group head of marketing.

“We hold the quality and sustainability of our suppliers’ products very highly. However, we weren’t experts in carbon. We were aware that it was a movement, but we certainly weren’t in any way involved.”

That changed when, during a meeting with supplier Accsys Technologies, Lathams was introduced to an architect who explained the significance of carbon in his product selection criteria. Above product aesthetics, performance and suitability, the architect rated carbon as the first thing he considered – specifically in the context of cladding projects where the large amount of wood cladding could create a big carbon sink.

“That triggered some ideas within us about the relevance and importance of carbon.”

When the pandemic hit, Lathams had time to examine what new projects it could focus on and carbon was highlighted. The company started looking at how it could measure the carbon impact of its products – both from a carbon footprint and biogenic (embodied carbon) point of view.

Realising it needed expert guidance, Lathams was advised by the Timber Trade Federation’s Tabitha Binding to contact several universities and ultimately Bangor was selected to take on the project.


After over 12 months of work, the now operational James Latham Carbon Calculator is designed to give a combined score or rating for its products based on carbon footprint and “locked in” stored carbon (biogenic), thereby increasing visibility of carbon impacts and directing customers towards more sustainable products.

The calculator covers just over 70% of the total Lathams product range and focuses on timber products, though in a following phase composite materials will be added to its scope.

The carbon footprint side of the tool calculates environmental impact by looking at the carbon footprint of products, from production through to delivery and storage at James Latham depots – a ‘cradle-to-warehouse gate’ basis, capturing greenhouse gas emissions up to the point that goods leave Lathams’ premises for delivery to the customer.

Each product receives a ‘Confidence’ rating from C1 – C4 (one being the highest), based on the confidence that Lathams has in the data used for the calculations. The higher the score, the higher the quality of the data points that have been reviewed, for example an audited and published EPD (Environmental Performance Declaration).

The carbon footprint scorecard is represented by a footprint logo, while the biogenic rating has a tree logo.

Lathams will be adding the carbon data to all quotations, delivery notes, and other key documentation to increase visibility around this issue.

Ewa Bazydlo, environmental manager at Lathams, explained that understanding around sustainability is not consistent across the industry.

“We’ve developed the calculator to help our customers to better understand the sustainability of the materials they choose as well as the expected performance levels that they offer,” she said.

“We needed a mechanism to rank our products and make it quick and easy for our customers to be able to specify more carbon conscious materials. As a large distributor, we have the relationships with the supply chain, which improves our ability to source and analyse the relevant data and make recommendations.

“We hope that others in the industry follow our lead and improve the transparency around these products so that we can work together to reduce construction’s impact on the environment.”

This aspect of increasing wider trade understanding, added Mr Devoil, was being aided with Lathams publishing a “Think You Know Carbon?” guide to provide an overview of the main issues in sustainability, a glossary of key terminologies and steps that architects and specifiers can take to be more sustainable in their designs.

Researchers Campbell Skinner and George Roberts of the BioComposites Centre took a lead in formulating the data tool.

“Companies have used eco-labels before, but the approach taken by Lathams is really innovative,” said Mr Skinner.

“For the first time that I’m aware, the confidence with which these footprints are presented is rated and placed foremost in the labelling.

“Latham’s customers are being given a clear indication of the transparency with which suppliers are reporting their carbon footprints and this will surely nudge more companies towards independently verified reporting schemes, such as EPDs.”


James Latham has a number of targets it wants to achieve through the Calculator project, including:

• Create a communications platform with customers and producers/suppliers

• Demonstrate knowledge and awareness of the issue and promote the use of timber in construction

• To become the recognised supplier of carbon conscious materials

• To provide information to architects, specifiers and designers which will inform their product choices

• To encourage manufacturers to provide EPDs to raise themselves in the confidence rating categories.

Increasing dialogue between Lathams and its suppliers is important, said Mr Devoil.

“Our goal is to encourage those manufacturers and suppliers that are currently in categories three and four to move up to categories one and two.”

Suppliers such as UPM and Accsys Technologies, which supply Lathams with the products WISA Plywood and Accoya modified wood respectively, already have a significant amount of their own data, which assists in formulating Confidence rating scores.

“Suppliers now realise the relevance of carbon to us,” added Mr Devoil. “This has moved almost from a corporate social responsibility topic into a commercial topic.”

With project decision makers now looking at carbon issues, the benefits of being able to calculate and demonstrate carbon in products should be obvious.

One construction innovation company which is embracing the Lathams approach is Kiss House.

“For the industry to seriously address climate change, we need transparency throughout the supply chain and for everyone in the sector to have a proper understanding of the varied environmental impacts that construction has,” said Mike Jacob, director of product and innovation at Kiss House.

“The Lathams carbon calculator is especially interesting because it addresses the quality of the data used head on and provides a score for this. We have been trying to understand the true impact of what we do at Kiss House and working with Lathams is a big step towards this and achieving transparency.”

Mr Devoil emphasised that the Carbon Calculator project was focused on carbon and even if some products don’t have top Confidence scores, they still met Lathams’ strict criteria in terms of procurement standards and performance quality. Some products also had great carbon credentials but they weren’t able yet to fully demonstrate it in order to achieve higher ratings.

Factoring in composite products is a harder process as there are different materials involved – such as panel products with ABS edging or phenolic laminations.

“That’s coming in phase two, but we wanted to launch with the timber products first,” said Mr Devoil.

The vast majority of Lathams’ timber and wood products are already covered by the Calculator.

To promote the initiative, a series of seminars and white board videos are being organised with Lathams’ creating a tree character to narrate a better understanding of carbon, while the company will also make a big splash at FutureBuild in March.

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While the Carbon Calculator is a big project for Lathams, there are also other significant developments as the company goes into its 265th year in 2022.

It is developing a digital showroom aimed at the architect and design community. The website features software that is able to depict the detail of grain, textures and light reflection on products, with a mood board function to help designers select products.

An extensive digital library of products is expected to be a game changer in terms of the company’s ability to effectively show specifiers its product range.

This links in with a central sampling service which aids quick and simple delivery of samples and the ability to book a live / digital appointment with Lathams representatives.

It also has developed a digital sales team headed by Dave Green – group digital sales champion – to exploit the opportunities of digital sales channels.

The logos demonstrating Biogenic Carbon and Carbon Footprint confidence ratings
The logos demonstrating Biogenic Carbon and Carbon Footprint confidence ratings
Accoya modified wood is a good example of a Lathams stocked product with a strong carbon data set