If you’re researching Accoya versus hardwood for wooden sash windows, you’re probably not looking for the cheapest option.
You’re looking for long-term value, visual authenticity, and confidence that the windows you install today won’t become a maintenance headache in ten years’ time.
This is one of the most common (and sensible) questions we hear from London homeowners with period properties, particularly in areas like Chelsea, Fulham, Putney, Richmond, and across Surrey, where heritage matters and expectations are high.
In this article, we’ll break down the real cost differences between Accoya and traditional hardwood sash windows, not just the upfront price, but what drives those prices, what affects longevity, and which option genuinely represents better value over time.
Accoya is not a species of wood; it’s a modified softwood, altered at a molecular level through an acetylation process that dramatically improves its performance.
That process is the first major cost driver.
Accoya starts as sustainably sourced softwood, which is then treated to make it:
This modification process adds cost long before the timber ever reaches a joinery workshop.
Because Accoya is so stable, it’s typically used by high-end sash window specialists, not general builders.
That means:
The material rewards good joinery, but also exposes poor workmanship.
As a result:
That confidence is built into the price.
Hardwood has been used in British sash windows for centuries, and when done properly, it can still perform beautifully.
However, “hardwood” covers a wide range of qualities, and cost varies enormously depending on what’s actually being used.
True, durable hardwoods (such as sapele or oak) cost significantly more than fast-grown, lower-grade alternatives like Meranti, which should be avoided at all costs for exterior window use.
Prices rise when:
Hardwood is a natural, living material, it moves!
To compensate:
All of this increases manufacturing time and cost.
Well made hardwood sash windows still require:
The better the installer, the higher the labour cost, but also the better the long term result.
Not all Accoya sash windows are equal, despite the material being the same.
Here’s why prices vary:
Accoya performs best when:
Cheaper suppliers often simplify designs to save time.
Premium installations use:
Lower cost options may still require repainting far sooner.
Companies confident in their workmanship:
That reassurance has a cost, but also value.
Visit our pricing article to learn more about sash window costs
This is where homeowners can get caught out.
When hardwood sash windows are significantly cheaper than the market average, it’s usually due to one (or more) of the following:
“Hardwood” without a specific name tells you very little.
It may indicate:
All of which increase the risk of early movement and decay.
Some companies:
The initial price is lower, but so is performance and lifespan.
Cheaper hardwood installations often assume:
Those costs don’t appear on the quote, but they arrive later.
This is where the conversation really matters.
Over 20 – 30 years, repainting alone can materially affect total cost.
Both materials can last decades if properly made and maintained, but Accoya tends to deliver that lifespan with less intervention.
For homeowners who value long lasting predictability, this matters.
This depends on priorities, not just budget.
Neither option is “right” for everyone, and anyone telling you otherwise isn’t being fully transparent.
At Novells, we sit firmly in the premium but transparent category.
Our pricing reflects:
We’re rarely the cheapest, and deliberately so.
But we’re also very clear about what you’re paying for, and just as importantly, what you’re avoiding.
Choosing between Accoya and hardwood sash windows isn’t about trends or marketing — it’s about risk, value, and longevity.
If you’ve read this far, you now understand:
Whether you choose Accoya or hardwood, the most important thing is working with a company that explains the trade offs honestly.
And with that knowledge, you’re now in a strong position to make a decision that suits your home and your future.
If you’d like to explore this further, the next logical step is understanding maintenance costs over 20 30 years, or how Accoya performs in conservation areas, both of which we’re happy to explain, transparently and without pressure.
Accoya is often considered better than traditional hardwood for sash windows when long term stability, lower maintenance, and predictable performance are priorities. Its modified structure makes it far less prone to swelling, shrinking, and paint failure than most hardwoods. However, high quality hardwood sash windows can still perform very well when made from the right species and properly maintained. The better option depends on how long you plan to stay in the property and how much ongoing maintenance you’re comfortable with.
Accoya sash windows typically last longer with less intervention because the timber is exceptionally stable and highly resistant to rot and decay. This stability helps protect joints and paint finishes over time. Hardwood sash windows can also last for decades, but their lifespan is more dependent on timber quality, installation standards, and regular maintenance. In practice, Accoya often delivers a longer service life with fewer repairs.
Accoya sash windows usually cost more upfront than standard hardwood sash windows, largely due to the modified timber process and the higher joinery standards required. However, the overall cost difference often narrows over time, as Accoya typically requires less frequent repainting and fewer repairs. Hardwood prices vary widely depending on the species used, meaning some high quality hardwood options can be similarly priced to Accoya.
Accoya is not a species of wood; it’s a modified softwood, altered at a molecular level through an acetylation process that dramatically improves its performance. That process is the first major cost driver. You can read more about that in the article above.
As Co-founder of Novells Sash Windows, Philip has spent over 20 years perfecting the craft of designing, supplying, and fitting luxury wooden double-glazed box sash windows.
A family-run business led by Philip and his wife Nicola, Novells has fitted thousands of wooden windows across London and Surrey, with clients including Vivienne Westwood and the Victoria & Albert Museum.
