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sash window timber

Timber sash windows

We offer a range of timber products specially selected to create beautiful and long lasting sash windows. Our range includes hardwood and softwood.

We are big on Accoya

Historically all of our new joinery, sashes and sash boxes were made entirely out of hardwood, typically Sapele. Sapele is a sustainable hardwood that is very durable, has a very tight grain so takes a good paint finish and is lightweight, which makes it ideal for windows. We still offer a Sapele as an option, but we are increasingly using the timber Accoya as it is a far superior wood.   

Why have we switched?  

There are several reasons why we have switched from Sapele to Accoya as our number one choice of timber. Some of the key reasons are: 

  • It’s incredibly durable – This makes it a perfect choice for sash windows as it can withstand the day to day challenges that windows face.  
  • It’s water-resistant and does not rot - Need we say any more. Its water-resistant properties make Accoya the standout choice for sash windows giving us the peace of mind that what we will install does not rot.  
  • Accoya is sustainable - We love that Accoya is sustainably sourced. It is modified timber in which a process called acetylation, making it a sustainable wood source that is not only good or your windows but also great for our planet.  
  •  It’s incredibly reliable - Guaranteed for over 50 years above sea level! Meaning Accoya can defy the elements and perform for decades.  
  • It’s perfect for windows - Rot proof, durable and improving thermal insulation, there isn’t a better choice of wood for windows.

A deep dive into Accoya  

Accoya is the brand name of a treated wood created via a non-toxic treatment and uses fast-growing softwood timber from sustainable sources, which creates a high-performance wood, ideal for outdoor use. 

The treated wood has very high durability and dimensional stability, allowing for reduced maintenance and gives environmental advantages over slow-growing hardwoods, woods treated with toxic chemicals, and non-renewable carbon-intensive materials such as plastics. 

Read more about Accoya on the website

Client testimonials

Case studies

We installed 14 new hardwood double glazed sashes into this stunning Victorian house in Kingston.

Our other services

Sash window draught proofing

Servicing and draught-proofing

If your sash windows have broken cords or are stiff or jammed shut then this service will restore them to their original smooth working order.

Georgian sash window

Sash window repair and restoration

We completely and sympathetically restore your windows, so they will look like new without losing any of their original features.

Hardwood double glazed sash windows

New hardwood double glazing

If you do not require complete window replacement we can make new double glazed timber sashes to fit your original box sash frames.

Victorian sash window

New hardwood sash boxes

We can supply and fit new hardwood sash boxes complete with double glazed sashes that exactly replicate your original windows.