Why Embodied Carbon Matters for Dealers of Timber Buildings

Embodied carbon is the greenhouse gas emitted in making, transporting and installing building materials, and at the end of their life. Tenders and corporate buyers may ask for it. This guide explains what the term covers, where a figure has to come from, what EU rules ask, and what a dealer can say about a timber building without inventing numbers.

The guide gives no carbon figures of its own. A figure for a material is valid for the product and the producer it was calculated for, and a figure for a building is the result of a calculation for that building.

Where a Carbon Figure Comes From

For a product: an Environmental Product Declaration (EPD), drawn up for a specific product of a specific producer and verified by a third party
For a building: a life-cycle assessment of the building, which adds up the products, the transport, the work on site, the use of the building and the end of its life
For the carbon stored in wood: a calculation of the biogenic carbon content of the wood in the product

Figures taken from general databases describe an average product. They help to understand orders of magnitude, but they are not a statement about the product that a dealer sells.

What Is Different About Timber

A tree takes up carbon dioxide while it grows, and the carbon stays in the wood for as long as the wood is in use. Concrete and steel do not store carbon in this way. How a timber building compares with a building in another material depends on the design, on the products chosen and on what happens at the end of life, and it is established by a life-cycle assessment of the project. A comparison in figures belongs in that assessment.

What EU Rules Ask

The recast Energy Performance of Buildings Directive, Directive (EU) 2024/1275, brings life-cycle carbon into the rules for new buildings:

Article 7(2): member states ensure that the life-cycle global warming potential (GWP) is calculated and disclosed in the energy performance certificate, from 1 January 2028 for new buildings with a useful floor area above 1,000 m², and from 1 January 2030 for all new buildings
Article 7(5): by 1 January 2027 each member state publishes a roadmap for limit values on the life-cycle GWP of new buildings, with targets from 2030
Annex III: the life-cycle GWP is given as a figure for each life-cycle stage, in kg of CO2 equivalent per m² of useful floor area, over a reference study period of 50 years; the calculation follows EN 15978, and product data calculated under the Construction Products Regulation is used when it is available

A directive is put into national law by each member state, so the rule that a project meets is the national one. Read the national text before quoting a threshold.

How Dealers Can Use Carbon Information

Tenders and Planning Applications

Where a tender or a planning authority asks for a carbon assessment, the assessment is made for the project by the designer or by a life-cycle assessor. The dealer supplies what the assessor needs:

The quantities of timber and of other materials in the building, from the specification and the packing list
The timber species and the country of manufacture
Product declarations, where a product has one
The transport route from the factory to the site

Sales Presentations

In a presentation, say what is known and name the source. A statement such as "timber stores carbon while the building stands" needs no figure. A statement with a figure needs the declaration or the assessment it comes from, with its date.

Reporting by Corporate Clients

Corporate clients who report on sustainability ask their suppliers for data. Pass on the documents that exist for the order, and do not fill gaps with estimates.

What Eurodita Can State

Timber: Nordic and Northern European spruce and pine, approximately 150,000 m³ processed per year on average
Drying: Nardi kilns dry the timber to a 12 to 14% moisture target; the drying system runs on electricity
Machining: components are cut on Hundegger CNC lines to the order drawings, so the cutting takes place in the factory and not on site
Transport: kits are shipped flat packed
Certification: Eurodita holds no FSC or PEFC chain-of-custody certificate of its own; see certifications

Which environmental documentation is available for an order is confirmed in the written quotation.

Frequently Asked Questions

What is the difference between embodied carbon and operational carbon?

Embodied carbon covers the emissions from making, transporting and installing the materials of a building, and from the end of their life. Operational carbon covers the emissions from heating, cooling and powering the building in use. The thermal performance of the complete envelope decides the second.

Can a dealer call a timber building carbon negative?

Only with a calculation for the product or the building that shows it, made to a named method and with the source stated. Without that calculation, say that timber stores carbon while the building stands.

How do glulam and solid log compare on embodied carbon?

Glulam adds steps to the process: the lamellae are dried and then glued. How much that changes the figure for a wall depends on the producer and the product, so the comparison is made from product declarations or in the life-cycle assessment of the project. See the guide to glulam wall profiles.

Does transport change the result?

Transport is one of the stages of a life-cycle assessment, and its share depends on the route and the mode of transport. The assessor calculates it for the project.

What should a dealer request from a manufacturer?

The specification with the quantities of material, the country of manufacture, any product declaration that exists for the product, and the documents on the origin of the timber that the order carries. See also the guide to the EU Deforestation Regulation.

Embodied Carbon in Timber vs Concrete vs Steel: What Dealers Can Say