Laura Keily, Head of Marketing at Accsys, the company behind Accoya, shares why durability, dimensional stability and lifecycle performance are reshaping timber specification for modern residential developments.
Please introduce yourself and Accoya.
I’m Laura Keily, Head of Marketing at Accsys, the company behind Accoya. My role gives me the opportunity to work closely with architects, developers, manufacturers and specification professionals across a wide range of projects, from residential homes to landmark commercial buildings. One of the things I enjoy most is helping people navigate the changing world of timber specification, where performance expectations are higher than ever before.
Accoya is a high-performance modified wood that combines the natural beauty of real wood with exceptional durability, dimensional stability and sustainability. It has been independently tested and proven in some of the world’s most demanding applications, which is why it’s increasingly being specified where long-term performance really matters.
Why is it no longer enough to choose timber simply by species when specifying materials for modern residential developments?
This is probably one of the biggest shifts we’ve seen over the past decade. Historically, timber was often selected almost entirely by species: oak, cedar, pine and so on. But the species only tells part of the story.
Today, architects and developers are asking a different question: “How will this material perform over the next 30 or 40 years?”
That’s where characteristics like dimensional stability, durability, coating performance and maintenance become far more important than the species itself. Two pieces of the same species can perform very differently depending on how they were grown, processed and modified.
That’s why the conversation has moved from “What species is it?” to “What evidence do we have that it will perform?”
What characteristics should developers be looking for when assessing long-term performance?
I always encourage developers to think beyond the day the project is handed over. A building only starts proving itself once people begin living in it.
The characteristics that matter most are dimensional stability, durability, moisture performance, coating life, maintenance requirements and independently verified sustainability credentials.
Those factors influence everything from homeowner satisfaction to maintenance budgets and warranty claims. Looking at performance over decades, rather than simply appearance on day one, usually leads to much better specification decisions.
Why does movement in timber matter so much for windows, doors and cladding?
One of the conversations I find myself having most often is about timber movement. It’s something many people underestimate, yet it’s behind a surprising number of performance issues.
When timber expands and contracts significantly, it puts stress on coatings, affects the fit of windows and doors and can impact the appearance of cladding over time. That’s why dimensional stability is so important. When the substrate remains stable, coatings last longer, components fit as intended and maintenance intervals are typically extended.
It’s one of the reasons products like Accoya have gained so much attention, because reducing movement helps improve the performance of the entire building system, not just the timber itself.
Sustainability claims are everywhere in the construction sector. What evidence should specifiers look for?
It’s encouraging that sustainability is now central to the conversation, but it also means there’s a huge amount of information and not all of it carries the same weight.
I always encourage specifiers to look beyond marketing claims and ask for independent evidence. Things like FSC® certification, Environmental Product Declarations (EPD), Chain of Custody certification and recognised third-party certifications provide much greater confidence than broad sustainability statements.
The strongest sustainability stories are always the ones supported by transparent, independently verified data.
What are the biggest misconceptions you encounter when discussing modified wood with architects, housebuilders and specification professionals?
One of the biggest misconceptions is that all timber performs in roughly the same way, and that modified wood is simply another version of treated timber.
In reality, modification technologies can fundamentally change how wood behaves. That’s particularly true with acetylation, which improves dimensional stability and durability while retaining the natural character of the wood.
I think many people are surprised by just how much performance can be improved without losing what makes wood such an attractive material in the first place.
Why should developers think about lifecycle performance instead of simply upfront material costs?
The purchase price is only one part of the financial picture. When developers look at a building over several decades, maintenance, repairs, repainting, replacement and warranty claims often have a much greater impact on total ownership costs than the initial material selection.
This is why more organisations are evaluating products based on whole-life value rather than purchase price alone. Materials that deliver predictable long-term performance help reduce risk, improve homeowner satisfaction and often provide a much stronger return over the life of the building.
How can selecting the right timber reduce ongoing maintenance costs for homeowners while also protecting the developer’s reputation?
Developers don’t just build homes, they build reputations. Homeowners rarely remember what timber species was used, but they certainly remember doors that stick, coatings that peel or cladding that requires unexpected maintenance.
Choosing materials with proven long-term performance reduces the likelihood of those issues occurring in the first place. That benefits the homeowner through lower maintenance and gives developers greater confidence that the quality they delivered on day one will still be reflected years later.
Looking beyond aesthetics, what practical characteristics separate a high-performance timber product from a standard timber solution?
For me, it’s really about predictability.
High-performance timber should provide consistent dimensional stability, proven durability, long coating life and independent evidence to support its claims.
It’s also important that those characteristics are repeatable from one project to the next. Architects and developers need confidence that the product will perform as expected, not just in ideal conditions, but in real-world applications over many years.
Ultimately, the best-performing timber products don’t simply look good when they’re installed; they continue performing long after the project has been completed.
What advice would you give to specifiers and developers when selecting timber for long term performance?
If there’s one thing I’d encourage specifiers and developers to do, it’s to ask more questions about long-term performance.
Timber has always been valued for its natural beauty, but today’s projects demand much more than appearance alone. We now have access to materials that can deliver outstanding aesthetics alongside exceptional durability, stability and sustainability.
The more the industry focuses on measurable performance rather than assumptions, the better outcomes we’ll achieve for buildings, homeowners and the environment.
About Accoya
Accoya is a high performance modified wood developed to combine the natural appearance and versatility of timber with enhanced durability and dimensional stability. Produced using a process known as acetylation, the wood is modified to reduce its ability to absorb water, helping to minimise the swelling and shrinkage that can affect conventional timber throughout its service life.
These characteristics make Accoya suitable for demanding external applications including windows, doors, cladding and other architectural elements where exposure to changing weather conditions can influence long term performance. Its dimensional stability can also support improved coating performance and extended maintenance intervals, helping specifiers and developers consider the material in terms of whole life performance rather than initial appearance or cost alone.
Sustainability is also central to the Accoya proposition. The timber is sourced from certified forests, while independently verified environmental information provides specifiers with greater transparency when assessing material choices.
Accoya offers an alternative approach to traditional timber specification. Rather than selecting wood principally according to species, it enables greater emphasis to be placed on measurable characteristics including durability, stability, maintenance requirements and lifecycle value. This combination of natural aesthetics and predictable performance makes it particularly relevant for residential projects where lasting quality is an important part of the specification.
