Environmental

AkzoNobel whitepaper makes the case for timber and high-performance coatings in lower-carbon buildings

Phil Black - PII Editor 35 minutes ago

26 7 minutes read

Key points

Listen to this article

New lifecycle assessment finds that, in the assessed scenarios, timber-based façades and window frames have lower cradle-to-grave carbon footprints than aluminium, steel and PVC alternatives.

AkzoNobel is marking World Green Building Week with the launch of The case for wood in more sustainable buildings, a new whitepaper developed in collaboration with the University of Amsterdam.

The whitepaper examines how responsibly sourced and properly protected timber can support lower-carbon building choices while delivering durability, robust performance and architectural quality. It also explores how material selection and protective coating systems can work together to help reduce a building’s overall lifecycle carbon footprint.

With embodied carbon becoming an increasingly important consideration for architects, engineers, developers and manufacturers, the choice of building materials can have a significant influence on the environmental performance of a project. The findings presented by AkzoNobel highlight the potential role of timber in sustainable construction while also emphasising the importance of protecting timber throughout its intended service life.

Lifecycle carbon assessment compares timber with aluminium, steel and PVC

The whitepaper presents findings from a comparative lifecycle assessment of representative façade panels and window frames made from wood and other commonly used materials, including aluminium, steel and PVC.

The assessment considers the full lifecycle of each system. This includes material production, coating application, use, maintenance, transport and end-of-life scenarios.

This cradle-to-grave approach is important because the carbon impact of a building material does not end when a product leaves the factory. Maintenance requirements, coating applications, transport, service life and eventual end-of-life treatment can all influence the overall carbon footprint.

The analysis found that wood-based façades and window frames had lower cradle-to-grave carbon footprints than the non-wood alternatives assessed.

The study also shows that the substrate is the primary driver of total carbon emissions. Coatings contribute a relatively small share, ranging from 4% to 37% of the assessed footprint depending on the material and application.

The findings therefore point towards the importance of considering the complete building system rather than assessing coatings or individual materials in isolation.

Three considerations for more sustainable building design

The whitepaper highlights three practical implications for architects, engineers, developers and manufacturers:

Material choice is the biggest lever: Selecting timber for suitable façade and window applications has the potential to reduce lifecycle carbon emissions compared with aluminium, steel and PVC alternatives.
Durability should be assessed over the whole building life: High-quality coating systems can have a slightly higher initial carbon contribution, but can extend maintenance and repair intervals and reduce the likelihood of premature replacement.
Specification must be application-led: Timber, coating systems, design, installation and maintenance strategies need to be considered together to achieve the required performance over the intended service life.

These considerations are particularly relevant as the construction sector looks beyond the initial carbon impact of materials and considers how products perform throughout the life of a building.

For timber construction, this means considering the relationship between the timber substrate, protective coating system, building design, installation and future maintenance requirements from the outset.

Timber coatings and lifecycle carbon footprint

The assessment used market-average Environmental Product Declarations (EPDs) for substrates and AkzoNobel Product Carbon Footprints (PCFs) for paints and coatings, with conservative assumptions applied to maintenance and end-of-life scenarios.

Environmental Product Declarations provide standardised information about the environmental performance of products based on lifecycle assessment. They can also support comparisons between different material and product options when specifying solutions for sustainable building projects.

In the assessed scenarios, coatings account for approximately 21% of the wood frame’s total carbon footprint, which also includes coating applications associated with maintenance, compared with 4% for aluminium.

However, that 21% is calculated against a much smaller total: approximately 19kg CO2e per square metre for a wood frame, compared with 93kg for aluminium.

Similarly, coatings account for approximately 37% of a wood façade panel’s total carbon footprint, compared with 13% for aluminium and 19% for steel.

Again, this higher percentage is calculated against a much smaller total: approximately 15kg CO2e per square metre for wood, compared with 28kg for aluminium and 99kg for steel.

The figures illustrate why percentages alone can give an incomplete picture when comparing building materials. Although coatings represent a larger proportion of the carbon footprint in the assessed timber scenarios, the overall carbon footprint of the timber systems remains substantially lower than the aluminium and steel alternatives assessed.

These findings reflect the whitepaper’s central message: the substrate is the dominant driver of total carbon footprint, while coatings create value by protecting the substrate and extending its service life.

Protecting timber to extend service life

The durability of timber is an important consideration when specifying wood for façades, windows, doors and other building applications.

Responsibly sourced timber can provide a lower-carbon alternative in suitable applications, but its performance depends on appropriate design, installation, protection and maintenance. AkzoNobel says that properly protected wood can provide lasting durability, robust performance and architectural quality.

Protective wood coatings therefore have a role that extends beyond appearance. By helping protect the timber substrate from the conditions it will experience during its service life, coating systems can contribute to durability and help reduce the frequency of maintenance, repair or premature replacement.

This makes coating specification an important part of the wider lifecycle assessment when comparing timber with alternative materials.

Industrial wood coatings for timber windows and façades

At the manufacturing stage, AkzoNobel supports manufacturers in translating project specifications into consistent industrial finishing systems for timber windows and façade components, helping protect the substrate and support the intended service life.

“Manufacturers of timber windows, doors and façade components need coating systems that deliver consistent quality and reliable performance at industrial scale,” says Sarah Skinner, Marketing Director, Wood Finishes at AkzoNobel. “Bringing the timber, coating system and finishing process together helps protect the substrate, extend service life and meet sustainability requirements without compromising production efficiency.

“By combining lifecycle data with our expertise in industrial coatings, we can help manufacturers choose the right technology for each application, from waterborne and low-VOC systems that can help reduce VOC emissions to UV LED-curable solutions that support faster processing and lower energy consumption. By helping manufacturers choose wood finishing systems that protect timber and extend its service life we can help preserve its carbon advantage and support more sustainable building choices.”

The focus on industrial finishing is particularly relevant for manufacturers producing timber windows, doors, façades and cladding components at scale. Consistency in the finishing process can be important for achieving the required appearance, durability and performance across manufactured components.

AkzoNobel also highlights the role of coating technology in helping manufacturers address production efficiency alongside sustainability objectives. Its portfolio includes waterborne and low-VOC systems as well as UV LED-curable technologies designed to support faster processing and lower energy consumption.

The wider role of timber in sustainable construction

The whitepaper also highlights the wider value of timber in the built environment.

Beyond its carbon profile, wood supports biophilic design, the integration of natural elements into built environments, contributing warmth and character.

The use of natural materials can therefore support both the environmental and architectural objectives of a building project. Timber can provide a distinctive visual finish while also offering flexibility in architectural design.

Engineered timber products such as cross-laminated timber panels and glue-laminated timber (glulam) structural beams and columns provide a high strength-to-weight ratio. This allows structures to be lighter than equivalent concrete or steel designs and can potentially reduce foundation requirements while simplifying transport and assembly.

Prefabricated timber elements can also be produced with high precision in factory conditions. This can enable rapid on-site installation while reducing construction waste.

These characteristics make engineered timber an increasingly relevant consideration for projects looking to combine structural performance, construction efficiency and lower-carbon building strategies.

Combining material choice with high-performance coatings

The findings of the whitepaper underline that sustainable building design is not simply a question of selecting one material over another.

Instead, architects, engineers, developers and manufacturers need to consider how materials perform throughout their intended service life.

For timber façades and windows, this includes selecting an appropriate timber substrate, specifying a suitable coating system and ensuring that the design, installation and maintenance strategy are aligned.

High-performance coatings can contribute to this approach by protecting timber from environmental exposure and helping maintain the performance and appearance of the finished component.

AkzoNobel’s wider approach to sustainable buildings includes the use of lifecycle assessment and environmental product declarations to provide greater transparency around the environmental performance of products. The company says lifecycle thinking is an important part of its sustainability work and its assessments use established lifecycle assessment methodologies.

Supporting sustainable building projects

AkzoNobel supports manufacturers, OEMs and project teams with industrial wood coatings and wood adhesives for applications including windows, doors, façades, cladding, furniture and cabinetry.

The company can help project teams compare material and coating options, recommend systems and maintenance strategies for specific applications and climates, support lifecycle assessments and green building certification programmes and collaborate on pilot projects and case studies.

This support reflects the growing importance of considering material performance and environmental impact together. For building designers and specifiers, lifecycle data can help inform decisions around materials, coatings and maintenance strategies while supporting wider sustainability objectives.

AkzoNobel also provides Environmental Product Declarations for a range of products used in sustainable building projects. EPDs can be used to support green building assessment schemes including BREEAM and LEED, helping provide greater transparency when comparing the environmental performance of building products.

Making the case for timber in lower-carbon buildings

The The case for wood in more sustainable buildings whitepaper makes the case for considering timber as part of a broader strategy for reducing the carbon footprint of buildings.

The lifecycle assessment indicates that, in the scenarios assessed, timber-based façades and window frames had lower cradle-to-grave carbon footprints than the aluminium, steel and PVC alternatives included in the study.

At the same time, the research highlights the importance of protecting timber and extending its service life. While coatings represent a proportion of the overall carbon footprint, their role in protecting the substrate means that coating specification needs to be considered alongside material selection, design, installation and maintenance.

For architects, engineers, developers and manufacturers looking at lower-carbon construction, the findings provide further evidence that material selection can be one of the most significant decisions affecting the lifecycle carbon footprint of a building.

The whitepaper also demonstrates why the performance of the complete building system needs to be considered. Choosing timber, specifying an appropriate high-performance coating and planning for long-term maintenance can all form part of an integrated approach to more sustainable building design.

The case for wood in more sustainable buildings whitepaper is available to download from AkzoNobel’s industrial wood coatings website.

For further information or to discuss a project-specific question, contact your local AkzoNobel representative.