The Specialist in Traditional Sash Windows is a FENSA Registered Company.

Accoya Windows & Doors

Accoya windows and doors are a sustainable, durable and secure option for your home.

Accoya Wooden Windows & Doors - Fitting and Installation

Accoya is the perfect durable, sustainable material for the construction of quality windows and doors. It is the industry’s leading timber. Harvested from sustainably sourced, fast-growing radiata pine trees, Accoya wood gets its strength and stability thanks to a special modification process called acetylation. Entirely non-toxic, this treatment gives it properties that exceed the durability of leading softwoods and hardwoods and benefits from a 50 year guarantee.

Our expert team of advisors, manufacturers and installers can use accoya timber to transform your:

  • Sash Windows
  • Casement Windows
  • Front Doors (e.g. Single Doors)
  • French Door Frames
  • Bi-Folding Door Frames

All our Accoya products come with a 50 year guarantee.

Request a FREE Quote

Complete the form below for a free, no obligation quote.

We’ll call you back within two working days.


0800 389 73 84


The benefits of accoya windows and doors:

  • Doors and windows made from accoya wood won’t shrink, swell or warp, meaning they won’t jam and scrape, unlike many other traditional woods.
  • Accoya is indigestible to microorganisms, making it less vulnerable to insects, fungi and rot.
  • Accoya windows are less susceptible to UV damage.
  • Designed to hold paint or varnish for longer, meaning your Accoya windows and doors will look great for years to come with minimal amounts of upkeep.
  • Low thermal conductivity helps to keep more heat in.

Why timber is the clear green choice

The manufacture of timber windows uses eight times less energy than the production of uPVC windows. Plastic window manufacture also releases toxic chemicals into the atmosphere, e.g. the harmful carcinogen benzene (released during laser cutting). We therefore exclusively use timber for our window and door frames, with Accoya being our most popular sustainable choice.


Learn more about accoya:


Why Choose The Specialist In Traditional Sash Windows

Here at The Specialist in Traditional Sash Windows, we never cut corners when it comes to ensuring environmentally friendly windows and doors – from materials to manufacture. 

We pride ourselves on our bespoke sash window services, quality of workmanship and careful installation, as well as dedicated aftercare. We want to help you get the most out of your home and our expert team will advise and inform you along every step of the way.

Guaranteed no-fuss after-sales service

We want you to be over the moon with your new windows or doors and our promise is simple. If there is something you are not happy with, no matter how small, we will come back and fix it, no quibbles.

Eco-Friendly Credentials

All our workshop machines are designed to reduce energy consumption and CO2 emissions.  We then use envionmentall friendly, sustainable grade A materials for our frames – redwood, hardwood or oak.

Bespoke, tailored service to your needs

Every element of the finished product is based on your exact desires, from the glazing to window furniture to the architraves used.

Your work is NEVER subcontracted - it’s all us

Unlike many other companies, we manufacture our windows and doors in our purpose-built, state-of-the-art Guildford workshop, an then our own full-time fitters will install them.


0800 389 7384

We supply, install and upgrade windows and doors to London & the South-East of England

Though our workshop and showroom are based in Guildford, Surrey, we endeavour to serve as much of the Surrey-East of England, including London, Surrey, Berkshire, Essex, Hampshire, Kent & Sussex.

"6 weeks after the work was completed I wished I'd had it done 10 years ago. Looks good and job well done."

Customer in London, May 2019

Articles about Sash Windows

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