Family Business since 1990
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Avon Timber Merchants is now closed for the festive holidays until our return on Friday, 2nd January 2026, reopening at 8:00 AM.

 

All orders placed on our website will be processed and delivered as soon as possible after our return in January 2026.

The quoting system remains available to use, however, it will not be monitored during the closure. Requests will be reviewed and processed promptly upon our return.

We would like to take this opportunity to wish all our customers a very Merry Christmas and a Happy New Year. Thank you for your continued support.

Warm regards,
The Website Administration Team

Avon Timber Merchants – Stock Take

Please note that we will be closed on Friday 29th May 2026.
We will be open as normal on Saturday 30th May 2026.

Warm regards,
The Website Administration Team

Window Boards

Window Boards & Sills

Window boards, also known as window sills, are designed to finish your internal windows by covering the gap between your window and wall. Our range of wooden window boards includes solid oak, pine, ash, walnut, tulipwood, sapele and MDF in various sizes to suit your needs. Elevate your home with your choice of one of two profiles; the modern square edge or the more traditional bullnose profile.

All machined by us the UK, if you are looking to order high quality window boards from an independent family-run business, check out our full range of made to order window boards or for bespoke sizes or materials contact Avon Timber today via [email protected].

 

Window Boards Information

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Solid Wooden Window Boards: We offer a selection of high-quality solid wooden window boards crafted from various premium wood species. Each type of wood provides unique aesthetic and functional benefits:

Appearance: Light to medium brown colour with a distinctive grain pattern.

Features: Strong, durable, and resistant to wear, making it ideal for high-traffic areas.

Appearance: Light-coloured wood with a straight grain and uniform texture.

Features: Tough and flexible, known for its excellent shock resistance.

Appearance: Reddish-brown hue with a fine, interlocked grain that creates a beautiful ribbon-like effect.

Features: Hard and dense, offering high durability and a luxurious look.

Appearance: Pale yellow to light brown with occasional streaks of green, purple, or black. Ideal for a painted finish.

Features: Lightweight yet strong, easy to work with, and has a smooth finish.

Appearance: Rich, dark brown colour with a straight grain and occasional waves.

Features: Exceptionally durable and resistant to decay, providing an elegant and timeless appeal.

Appearance: Light reddish-brown colour with a straight grain and even texture.

Features: Softwood that is easy to work with, lightweight, and has good insulation properties.

Our white primed moisture resistant MDF window board is an excellent choice for those seeking a durable and easy-to-install solution with a clean, finished look.

Appearance:

Pre-primed in a sleek white finish, ready for painting to match any interior décor. Smooth and consistent surface without visible grain, providing a modern and seamless look.

Features:

Moisture resistant, durable, easy to work with, and low maintenance.

We currently supply window boards in Pine, MDF, Oak, Ash, Sapele, Walnut and Tulipwood.

We can also machine window boards from other species, subject to availability.

If you're looking for something specific, please contact us via [email protected] and we’ll be happy to assist.

A windowboard, also known as an internal window sill, is the flat, horizontal surface at the bottom of a window on the inside of your home. It provides a nice finished look and can be used to place decorations like plants or pictures.

A window sill is the horizontal piece that runs along the length of the window, at the bottom of a window frame, on the outside of the building. It helps keep rainwater from entering your home.

A windowboard serves several important functions in a home:

1. Aesthetic Enhancement: Provides a finished, polished look and integrates the window into the room’s design.

2. Practical Surface: Creates a usable space for plants, photos, or décor.

3. Protection: Protects walls from condensation and wear.

4. Insulation: Helps reduce drafts and improves energy efficiency.

5. Structural Support: Helps maintain stability around the window opening.

When the ends are returned, it means they are rounded. On a bullnosed edge window board, the front edge profile is continued around the ends for a clean, finished appearance. Returned ends also help conceal any exposed end grain and provide a more professional finish once installed.

Our hardwood window boards are supplied freshly machined but unfinished as standard, while our MDF window boards are supplied pre-primed. This means they are ready for painting, staining, or varnishing on site.

Our standard thickness is 26mm, as this best suits our rounding cutter. However, we can provide thicknesses from 18mm upwards.

Please note:

Below 25mm, the bullnosed/returned end window board will not be fully rounded and will have a more pronounced curved profile.

Above 27mm, the edges are typically rounded on the top and bottom with a flatter front face.

Yes, all of our window boards are machined in-house to customer specification, allowing us to produce custom sizes to suit your project. Our online formula allows you to adjust width, length (up to 3m) and edges. If you’d like further customisation or longer lengths than 3m, please feel free to contact us via [email protected], and we’ll be happy to help out.

How much your window board overhangs is your own design choice. We’d usually recommend between 20mm to 50mm overhang at the front and 50mm side overhang (horns) on each side – adding 100mm to the full width of the board.

The amount a window board overhangs is largely a design preference and may vary depending on the style of the property and installation requirements.

As a general example, some installations use approximately 20mm–50mm front overhang, with side overhangs (horns) of around 50mm on each side. This would increase the overall length of the window board by approximately 100mm.

Side horns are typically left longer and trimmed on site by the installer to suit the wall conditions and achieve the desired appearance. This also allows for a more accurate fit, particularly where walls may not be perfectly square.

We recommend confirming requirements with your installer prior to ordering, as preferences and site conditions can vary.

Yes, however we recommend moisture-resistant MDF or hardwoods where appropriate. Proper sealing and finishing is advised after installation.

We take care to package window boards securely with bubble wrap, shrink wrap, and end protection to minimise damage in transit.

No, we do not cut out the horns prior to supply. Boards are supplied square so installers can cut them on site for a precise fit.

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