Sustainable Timber Windows: From Full Chain of Custody to Global Conservation with the World Land Trust

• 30 September 2025|
• News

In today’s construction industry, sustainability isn’t just a buzzword – it’s a fundamental requirement that’s reshaping how we approach building design and material selection. For architects, developers, and housebuilders, specifying sustainable timber windows represents a critical decision that impacts both environmental stewardship and long-term project value.

At Lomax + Wood, we’ve built our entire business philosophy around this principle, going far beyond standard industry practices to deliver genuinely sustainable solutions.

Why sustainability matters more than ever

The construction industry accounts for a large proportion of global carbon emissions, making sustainable material choices crucial for reducing environmental impact. Timber windows offer significant advantages over aluminium alternatives and UPVC windows, functioning as a natural insulator with lower carbon footprint throughout their life expectancy.

Unlike synthetic materials, timber is a renewable resource that actively stores carbon during growth. When sourced responsibly, timber windows can be carbon negative – meaning they remove more CO2 from the atmosphere than they produce during manufacturing and transport. This makes them an ideal sustainable choice for projects targeting net-zero or low-carbon objectives.

Balancing aesthetics and performance

For architects and developers working on conservation areas or listed buildings, sustainable timber windows provide the perfect balance between traditional aesthetics and modern energy efficiency standards. At Lomax + Wood, our timber sash windows and casement designs deliver superior thermal efficiency compared to traditional windows, helping reduce energy consumption whilst maintaining authentic architectural character.

Understanding chain of custody: the gold standard of sustainability

Many timber manufacturers claim sustainability credentials through basic FSC® or PEFC certification. However, there’s a crucial distinction that sets truly responsible suppliers apart: full Chain of Custody certification.

Chain of Custody certification tracks timber throughout the entire supply chain – from the moment a tree is felled in sustainably managed forests, through processing, manufacturing, and right to your finished product. This creates complete traceability, ensuring every piece of timber in your windows can be verified as genuinely sustainable.

We are proud to hold both FSC® and PEFC Chain of Custody certifications, ensuring that all timber we use is sourced from responsibly managed forests. Unlike other timber manufacturers, we hold full Chain of Custody certifications – this gives the timber we use in our windows and doors full traceability from forest to finished product.

The difference between basic certification and chain of custody

Many companies in the timber window market rely solely on purchasing FSC® certified timber without holding Chain of Custody certification themselves. This creates a gap in the supply chain where sustainability claims become difficult to verify.

Without Chain of Custody certification, manufacturers cannot guarantee that certified timber hasn’t been mixed with non-certified materials during processing. This means customers receive products with limited sustainability credentials, despite paying premium prices for supposedly “eco-friendly” windows.

Our full Chain of Custody certification eliminates these gaps. Every piece of timber entering our facility is tracked, processed separately, and can be traced back to its specific forest origin. This rigorous approach ensures that when you specify Lomax + Wood timber windows, you’re getting guaranteed sustainable materials with complete transparency.

Protecting people and communities

The Forest Stewardship Council’s Chain of Custody certification goes beyond environmental protection to safeguard the rights and wellbeing of workers throughout the timber supply chain.

This certification system ensures that every stage of production meets strict labour standards, abolishing child labour, eliminating forced labour, and protecting workers’ freedom of association.

By choosing FSC-certified windows from Lomax + Wood, you’re supporting fair employment practices.

The certification also extends to protecting Indigenous Peoples’ rights in timber-producing regions. This commitment to social responsibility means that when you specify our windows, you’re contributing to the wellbeing of communities from forest to factory.

Meeting RIBA and UK Timber Procurement standards

For architects and developers working on RIBA projects, compliance with the UK Timber Procurement Policy (TPP) is essential. Both FSC and PEFC Chain of Custody certifications are recognised as “Category A evidence” of legal and sustainable sourcing.

Lomax + Wood holds both FSC® Chain of Custody (registration number: C126169) and PEFC™ certifications, ensuring our timber windows and doors fully comply with these requirements, making specification straightforward for RIBA projects while supporting sustainable forestry practices.

Global conservation through the World Land Trust partnership

Sustainability extends beyond responsible sourcing – it requires active environmental stewardship. That’s why we’ve partnered with the World Land Trust, an organisation dedicated to protecting threatened wildlife habitats worldwide.

For every window or door we manufacture, we donate £1 to the World Land Trust’s Buy an Acre scheme. This direct contribution helps secure vital ecosystems that might otherwise be lost to deforestation or development. To date, our partnership has protected over 100 acres of threatened habitat, with the Trust securing more than 2,835,984 acres across 20 countries.

This initiative demonstrates our commitment to environmental responsibility beyond our immediate manufacturing processes. By choosing Lomax + Wood, you’re not just specifying sustainable timber windows – you’re actively contributing to global conservation efforts.

What’s the difference between FSC certification and Chain of Custody certification?

FSC® and PEFC certification verify that timber comes from responsibly managed forests. However, Chain of Custody certification goes further by tracking timber throughout the entire supply chain – from forest to finished product.

Do sustainable timber windows require more maintenance than other materials?

Modern sustainable timber windows require minimal maintenance when properly manufactured and finished. Our timber products feature high-quality factory finishes and engineered timber construction that extends life expectancy significantly. With proper care, sustainable timber windows can last 60+ years, often outlasting UPVC windows.

Made-to-order sustainable timber windows

At Lomax + Wood, environmental responsibility is central to our manufacturing philosophy. We source all timber used in our bespoke windows and doors with full Chain of Custody certification (FSC® or PEFC), ensuring complete traceability throughout the entire supply chain, from the forest to the finished product.

Across our range of flush casement and various sliding sash window styles, our made-to-order approach minimises waste whilst maximising performance. Rather than producing standard sizes that require on-site modifications, we manufacture each window to exact specifications. This precision manufacturing reduces material waste and ensures optimal energy efficiency for each opening.

Key features include:

• Energy efficiency: U-values as low as 1.0 W/m²K with triple glazing options
• Thermal performance: Superior insulation reduces heat loss and energy bills
• Acoustic properties: Up to 42dB noise reduction for improved indoor comfort
• Durability: Engineered timber construction extends life expectancy beyond traditional alternatives
• Natural warmth: Timber’s inherent insulating properties maintain comfortable indoor temperatures during colder months

Beyond manufacturing: our holistic sustainability approach

Sustainable timber windows represent just one element of our comprehensive environmental strategy:

• All company vehicles are fully electric, reducing transport emissions
• Digital workflows minimise paper consumption and streamline processes
• Online consultations reduce travel requirements for clients and our team
• Our head office and manufacturing facilities prioritise energy savings through modern systems

This holistic approach ensures that choosing Lomax + Wood delivers genuine environmental benefits throughout your project lifecycle.

Why sustainable timber windows make commercial sense

Beyond environmental benefits, sustainable timber windows deliver measurable commercial advantages:

The superior thermal efficiency of our products reduces ongoing heating costs, but sustainability credentials can also help to support planning applications, particularly in conservation areas.

Thermal efficiency is also a great way to futureproof projects, with environmental regulations increasingly favouring sustainable materials.

Environmentally conscious windows also offer widespread market appeal, as potential buyers increasingly prioritise sustainable features. Some insurers even offer preferential rates for sustainable construction!

Ready to specify truly sustainable timber windows?

Choosing sustainable timber windows shouldn’t mean compromising on quality, performance, or aesthetics.

Whether you’re working on heritage restoration, contemporary new builds, or large-scale commercial developments, our team can help specify the perfect sustainable timber windows for your requirements.

Contact Lomax + Wood today for expert guidance on sustainable timber windows.

Complete our online contact form or call 01277 353857 to arrange your free consultation and quotation. Let’s build a more sustainable future together.