Bespoke Solid Oak Window Sills – Premium Joinery Grade Oak, Made to Measure
Handcrafted solid oak window sills made to measure in our Pembrokeshire workshop and delivered nationwide across the UK.
Why Choose Our Oak Sills
- ✔ Solid European oak
- ✔ Made to your exact size
- ✔ Choice of live edge or square edge
- ✔ Handmade with love
See your chosen finish on real solid oak before ordering.
Solid Oak Window Sills & Boards - Made to Measure
Bespoke solid oak window sills, handcrafted from kiln-dried French oak and cut precisely to your measurements.
Each sill is machined in-house from kiln-dried, joinery-grade European oak and planed and sanded to a smooth, furniture-quality finish. Whether you’re renovating a period property or adding warmth to a modern interior, our bespoke oak window boards add depth, character and natural beauty to any room.
Made to Measure - Cut to the Millimeter
Every oak board is cut precisely to your required dimensions
We manufacture bespoke sizes to fit any alcove, recess or wall opening. Simply enter your measurements when ordering and we’ll produce your sill to the exact millimetre.
For wider boards (typically over 150mm), sections may be professionally joined to achieve the required depth. This is carefully matched to maintain a natural grain flow and seamless appearance.
Premium Kiln Dried French Oak
We use thick, kiln-dried French oak to ensure quality, stability and longevity.
✔ Joinery grade timber
✔ Planed and sanded to a fine finish
✔ Suitable for oiling, staining or waxing
✔ Solid oak – not veneered or MDF wrapped
As oak is a natural product, each board will have unique grain patterns, knots and tonal variation — part of what makes every piece individual.
Solid Oak Window Sills & Boards - Made to Measure
Bespoke solid oak window sills, handcrafted from kiln-dried French oak and cut precisely to your measurements.
Each sill is machined in-house from kiln-dried, joinery-grade European oak and planed and sanded to a smooth, furniture-quality finish. Whether you’re renovating a period property or adding warmth to a modern interior, our bespoke oak window boards add depth, character and natural beauty to any room.
Made to Measure - Cut to the Millimeter
Every oak board is cut precisely to your required dimensions
We manufacture bespoke sizes to fit any alcove, recess or wall opening. Simply enter your measurements when ordering and we’ll produce your sill to the exact millimetre.
For wider boards (typically over 150mm), sections may be professionally joined to achieve the required depth. This is carefully matched to maintain a natural grain flow and seamless appearance.
Premium Kiln Dried French Oak
We use thick, kiln-dried French oak to ensure quality, stability and longevity.
✔ Joinery grade timber
✔ Planed and sanded to a fine finish
✔ Suitable for oiling, staining or waxing
✔ Solid oak – not veneered or MDF wrapped
As oak is a natural product, each board will have unique grain patterns, knots and tonal variation — part of what makes every piece individual.
Our solid oak sills are available with two edge styles so you can choose the look that best suits your space.
Square Edge
A clean, straight edge with a modern and refined appearance.
This option works well in contemporary kitchens, modern interiors and minimalist spaces where a crisp, uniform finish is preferred.
Live Edge
A natural “waney” edge that follows the original shape of the tree.
This keeps the organic character of the oak and creates a more rustic, unique look, ideal for farmhouse kitchens, cottages and character homes.
Because live edge shelves follow the natural grain of the timber, each shelf will have its own individual shape and character.
Both edge styles are carefully sanded and prepared so they are smooth to the touch and ready for finishing or installation.
Our solid oak sills are available with two edge styles so you can choose the look that best suits your space.
Square Edge
A clean, straight edge with a modern and refined appearance.
This option works well in contemporary kitchens, modern interiors and minimalist spaces where a crisp, uniform finish is preferred.
Live Edge
A natural “waney” edge that follows the original shape of the tree.
This keeps the organic character of the oak and creates a more rustic, unique look, ideal for farmhouse kitchens, cottages and character homes.
Because live edge shelves follow the natural grain of the timber, each shelf will have its own individual shape and character.
Both edge styles are carefully sanded and prepared so they are smooth to the touch and ready for finishing or installation.
Sill Thickness Guide
Our solid oak shelves are available in a range of thicknesses, allowing you to choose the style and visual weight that best suits your space.
26mm – Slim & Minimal
A clean, lighter sill profile that works well in modern interiors, bathrooms, or spaces where a subtle look is preferred.
33mm – Most Popular
Our most commonly chosen thickness.
It provides a balanced, substantial appearance that works perfectly in kitchens, bedrooms and living rooms.
42mm – Chunky & Characterful
A thicker sill with a stronger visual presence.
Ideal for rustic interiors, statement windows, or where a more traditional solid oak look is desired.
55mm – Extra Chunky Statement Sill
Our thickest option, creating a bold and substantial sill that becomes a real feature within the room.
Perfect for larger rooms and windows, bay windows, window seats etc
All sill are made from solid kiln-dried Europen oak, carefully planed and sanded to create a smooth, premium finish.
Sill Thickness Guide
Our solid oak shelves are available in a range of thicknesses, allowing you to choose the style and visual weight that best suits your space.
26mm – Slim & Minimal
A clean, lighter sill profile that works well in modern interiors, bathrooms, or spaces where a subtle look is preferred.
33mm – Most Popular
Our most commonly chosen thickness.
It provides a balanced, substantial appearance that works perfectly in kitchens, bedrooms and living rooms.
42mm – Chunky & Characterful
A thicker sill with a stronger visual presence.
Ideal for rustic interiors, statement windows, or where a more traditional solid oak look is desired.
55mm – Extra Chunky Statement Sill
Our thickest option, creating a bold and substantial sill that becomes a real feature within the room.
Perfect for larger rooms and windows, bay windows, window seats etc
All sill are made from solid kiln-dried Europen oak, carefully planed and sanded to create a smooth, premium finish.
Delivery & Lead Time
Current lead time: Approximately 2–3 weeks
We ship Nationwide across the UK using trusted courier networks, delivery is only available on weekdays.
Delivery & Lead Time
Current lead time: Approximately 2–3 weeks
We ship Nationwide across the UK using trusted courier networks, delivery is only available on weekdays.
Installation Guidance
Solid oak is a natural, structural timber and should be installed correctly to ensure long-term stability and performance.
Acclimatisation
Before installation, we recommend allowing your oak window sill to acclimatise in the room where it will be fitted for several days. This allows the timber to adjust to the ambient temperature and humidity levels.
- Store flat
- Keep away from direct heat sources
- Do not lean upright against a wall
Supporting the Weight
Oak window sills are solid and heavy. Proper support is essential.
- Ensure the sill is fully supported across its width
- Use appropriate brackets or battens where required
- Avoid leaving large unsupported spans
For installations above radiators, allow airflow to prevent excessive heat build-up beneath the timber.
Fixing Advice
- Secure using suitable fixings into masonry or framing
- Avoid over-tightening screws
- Always allow for natural expansion and contraction
We recommend fixing the sill close to the delivery date to minimise movement prior to installation.
If you are unsure, consult a qualified carpenter or joiner.If you are unsure, consult a qualified carpenter or joiner.
Installation Guidance
Solid oak is a natural, structural timber and should be installed correctly to ensure long-term stability and performance.
Acclimatisation
Before installation, we recommend allowing your oak window sill to acclimatise in the room where it will be fitted for several days. This allows the timber to adjust to the ambient temperature and humidity levels.
- Store flat
- Keep away from direct heat sources
- Do not lean upright against a wall
Supporting the Weight
Oak window sills are solid and heavy. Proper support is essential.
- Ensure the sill is fully supported across its width
- Use appropriate brackets or battens where required
- Avoid leaving large unsupported spans
For installations above radiators, allow airflow to prevent excessive heat build-up beneath the timber.
Fixing Advice
- Secure using suitable fixings into masonry or framing
- Avoid over-tightening screws
- Always allow for natural expansion and contraction
We recommend fixing the sill close to the delivery date to minimise movement prior to installation.
If you are unsure, consult a qualified carpenter or joiner.If you are unsure, consult a qualified carpenter or joiner.
Timber Variation & Natural Characteristics
Oak is a natural material, and every board is unique. No two window sills will ever look identical — and that’s part of the beauty.
Colour variation
Solid oak can vary in tone from light golden hues to deeper honey shades. Over time, exposure to light will naturally mellow and deepen the colour. This is not a defect — it is a natural characteristic of genuine solid oak.
Grain and knots
You may see natural knots, grain variation, small checks or character markings, and subtle colour shifts. These features add authenticity and character to your window sill.
Joined boards (for wider widths)
For widths generally over 150mm+, boards may be professionally joined to achieve the required depth. This is done to prevent movement / cupping within the board. We carefully match grain and tone to ensure a seamless, natural appearance. All joints are structurally secure and finished to the same high standard.
Natural movement
As a natural timber product, oak may expand or contract slightly depending on environmental conditions. Correct installation and acclimatisation will minimise movement.
Timber Variation & Natural Characteristics
Oak is a natural material, and every board is unique. No two window sills will ever look identical — and that’s part of the beauty.
Colour variation
Solid oak can vary in tone from light golden hues to deeper honey shades. Over time, exposure to light will naturally mellow and deepen the colour. This is not a defect — it is a natural characteristic of genuine solid oak.
Grain and knots
You may see natural knots, grain variation, small checks or character markings, and subtle colour shifts. These features add authenticity and character to your window sill.
Joined boards (for wider widths)
For widths generally over 150mm+, boards may be professionally joined to achieve the required depth. This is done to prevent movement / cupping within the board. We carefully match grain and tone to ensure a seamless, natural appearance. All joints are structurally secure and finished to the same high standard.
Natural movement
As a natural timber product, oak may expand or contract slightly depending on environmental conditions. Correct installation and acclimatisation will minimise movement.
Frequently Asked Questions
Are your window sills solid oak?
Yes. All of our window sills are manufactured from solid kiln-dried European oak. We do not use veneer or MDF-wrapped products.
Can you make them to my exact size?
Yes. Every window sill is cut precisely to the millimetre to match your measurements.
What thickness should I choose?
This depends on the look you want and the size of the opening. Thicker boards provide a more substantial, architectural feel and are ideal for larger windows.
Can I install an oak window sill / shelf above a radiator?
Yes, provided adequate airflow is maintained and the sill is properly supported. Oak is durable, but excessive heat build-up should be avoided.
Do the boards come pre-finished?
Boards are supplied planed and sanded to a fine finish, ready for oiling, staining or sealing to suit your interior.
How long is the lead time?
Current lead time is approximately 2–3 weeks from order completion.
Will my board look exactly like the photos?
Each board is unique due to natural grain and colour variation. While the quality and finish are consistent, no two pieces will be identical.
Frequently Asked Questions
Are your window sills solid oak?
Yes. All of our window sills are manufactured from solid kiln-dried European oak. We do not use veneer or MDF-wrapped products.
Can you make them to my exact size?
Yes. Every window sill is cut precisely to the millimetre to match your measurements.
What thickness should I choose?
This depends on the look you want and the size of the opening. Thicker boards provide a more substantial, architectural feel and are ideal for larger windows.
Can I install an oak window sill / shelf above a radiator?
Yes, provided adequate airflow is maintained and the sill is properly supported. Oak is durable, but excessive heat build-up should be avoided.
Do the boards come pre-finished?
Boards are supplied planed and sanded to a fine finish, ready for oiling, staining or sealing to suit your interior.
How long is the lead time?
Current lead time is approximately 2–3 weeks from order completion.
Will my board look exactly like the photos?
Each board is unique due to natural grain and colour variation. While the quality and finish are consistent, no two pieces will be identical.
At Celtic Timber, sustainability is at the heart of everything we do. We source our timber from sustainably sourced certified forests, ensuring responsible management and protection of natural resources.
We also actively contribute to reforestation and rewilding projects across the UK, planting over 12,000 trees on our own land. By choosing our products, you’re supporting a company dedicated to reducing environmental impact and preserving the planet for future generations.
At Celtic Timber, sustainability is at the heart of everything we do. We source our timber from sustainably sourced certified forests, ensuring responsible management and protection of natural resources.
We also actively contribute to reforestation and rewilding projects across the UK, planting over 12,000 trees on our own land. By choosing our products, you’re supporting a company dedicated to reducing environmental impact and preserving the planet for future generations.
Returns & Peace of Mind
We stand by the quality of our products and want you to order with confidence.
We offer a 30-day returns policy on all non-bespoke items. If for any reason you’re not completely satisfied, please contact us within 30 days of receiving your order and we’ll be happy to assist.
If your item arrives damaged or incorrect, let us know as soon as possible and we’ll arrange a replacement or agree an appropriate resolution quickly and fairly.
To qualify for a refund, items must be returned unused and in their original packaging.
Return shipping costs are the responsibility of the customer, except where the return is due to damage in transit or an error on our part.
For bespoke or made-to-measure items, please note that these are manufactured specifically to your dimensions and are therefore non-returnable unless faulty.
Returns & Peace of Mind
We stand by the quality of our products and want you to order with confidence.
We offer a 30-day returns policy on all non-bespoke items. If for any reason you’re not completely satisfied, please contact us within 30 days of receiving your order and we’ll be happy to assist.
If your item arrives damaged or incorrect, let us know as soon as possible and we’ll arrange a replacement or agree an appropriate resolution quickly and fairly.
To qualify for a refund, items must be returned unused and in their original packaging.
Return shipping costs are the responsibility of the customer, except where the return is due to damage in transit or an error on our part.
For bespoke or made-to-measure items, please note that these are manufactured specifically to your dimensions and are therefore non-returnable unless faulty.
Bespoke Solid Oak Window Sills – Premium Joinery Grade Oak, Made to Measure
Why Choose Our Oak Sills
- ✔ Solid European oak
- ✔ Made to your exact size
- ✔ Choice of live edge or square edge
- ✔ Handmade with love
See your chosen finish on real solid oak before ordering.
Solid Oak Window Sills & Boards - Made to Measure
Bespoke solid oak window sills, handcrafted from kiln-dried French oak and cut precisely to your measurements.
Each sill is machined in-house from kiln-dried, joinery-grade European oak and planed and sanded to a smooth, furniture-quality finish. Whether you’re renovating a period property or adding warmth to a modern interior, our bespoke oak window boards add depth, character and natural beauty to any room.
Made to Measure - Cut to the Millimeter
Every oak board is cut precisely to your required dimensions
We manufacture bespoke sizes to fit any alcove, recess or wall opening. Simply enter your measurements when ordering and we’ll produce your sill to the exact millimetre.
For wider boards (typically over 150mm), sections may be professionally joined to achieve the required depth. This is carefully matched to maintain a natural grain flow and seamless appearance.
Premium Kiln Dried French Oak
We use thick, kiln-dried French oak to ensure quality, stability and longevity.
✔ Joinery grade timber
✔ Planed and sanded to a fine finish
✔ Suitable for oiling, staining or waxing
✔ Solid oak – not veneered or MDF wrapped
As oak is a natural product, each board will have unique grain patterns, knots and tonal variation — part of what makes every piece individual.
Solid Oak Window Sills & Boards - Made to Measure
Bespoke solid oak window sills, handcrafted from kiln-dried French oak and cut precisely to your measurements.
Each sill is machined in-house from kiln-dried, joinery-grade European oak and planed and sanded to a smooth, furniture-quality finish. Whether you’re renovating a period property or adding warmth to a modern interior, our bespoke oak window boards add depth, character and natural beauty to any room.
Made to Measure - Cut to the Millimeter
Every oak board is cut precisely to your required dimensions
We manufacture bespoke sizes to fit any alcove, recess or wall opening. Simply enter your measurements when ordering and we’ll produce your sill to the exact millimetre.
For wider boards (typically over 150mm), sections may be professionally joined to achieve the required depth. This is carefully matched to maintain a natural grain flow and seamless appearance.
Premium Kiln Dried French Oak
We use thick, kiln-dried French oak to ensure quality, stability and longevity.
✔ Joinery grade timber
✔ Planed and sanded to a fine finish
✔ Suitable for oiling, staining or waxing
✔ Solid oak – not veneered or MDF wrapped
As oak is a natural product, each board will have unique grain patterns, knots and tonal variation — part of what makes every piece individual.
Our solid oak sills are available with two edge styles so you can choose the look that best suits your space.
Square Edge
A clean, straight edge with a modern and refined appearance.
This option works well in contemporary kitchens, modern interiors and minimalist spaces where a crisp, uniform finish is preferred.
Live Edge
A natural “waney” edge that follows the original shape of the tree.
This keeps the organic character of the oak and creates a more rustic, unique look, ideal for farmhouse kitchens, cottages and character homes.
Because live edge shelves follow the natural grain of the timber, each shelf will have its own individual shape and character.
Both edge styles are carefully sanded and prepared so they are smooth to the touch and ready for finishing or installation.
Our solid oak sills are available with two edge styles so you can choose the look that best suits your space.
Square Edge
A clean, straight edge with a modern and refined appearance.
This option works well in contemporary kitchens, modern interiors and minimalist spaces where a crisp, uniform finish is preferred.
Live Edge
A natural “waney” edge that follows the original shape of the tree.
This keeps the organic character of the oak and creates a more rustic, unique look, ideal for farmhouse kitchens, cottages and character homes.
Because live edge shelves follow the natural grain of the timber, each shelf will have its own individual shape and character.
Both edge styles are carefully sanded and prepared so they are smooth to the touch and ready for finishing or installation.
Sill Thickness Guide
Our solid oak shelves are available in a range of thicknesses, allowing you to choose the style and visual weight that best suits your space.
26mm – Slim & Minimal
A clean, lighter sill profile that works well in modern interiors, bathrooms, or spaces where a subtle look is preferred.
33mm – Most Popular
Our most commonly chosen thickness.
It provides a balanced, substantial appearance that works perfectly in kitchens, bedrooms and living rooms.
42mm – Chunky & Characterful
A thicker sill with a stronger visual presence.
Ideal for rustic interiors, statement windows, or where a more traditional solid oak look is desired.
55mm – Extra Chunky Statement Sill
Our thickest option, creating a bold and substantial sill that becomes a real feature within the room.
Perfect for larger rooms and windows, bay windows, window seats etc
All sill are made from solid kiln-dried Europen oak, carefully planed and sanded to create a smooth, premium finish.
Sill Thickness Guide
Our solid oak shelves are available in a range of thicknesses, allowing you to choose the style and visual weight that best suits your space.
26mm – Slim & Minimal
A clean, lighter sill profile that works well in modern interiors, bathrooms, or spaces where a subtle look is preferred.
33mm – Most Popular
Our most commonly chosen thickness.
It provides a balanced, substantial appearance that works perfectly in kitchens, bedrooms and living rooms.
42mm – Chunky & Characterful
A thicker sill with a stronger visual presence.
Ideal for rustic interiors, statement windows, or where a more traditional solid oak look is desired.
55mm – Extra Chunky Statement Sill
Our thickest option, creating a bold and substantial sill that becomes a real feature within the room.
Perfect for larger rooms and windows, bay windows, window seats etc
All sill are made from solid kiln-dried Europen oak, carefully planed and sanded to create a smooth, premium finish.
Delivery & Lead Time
Current lead time: Approximately 2–3 weeks
We ship Nationwide across the UK using trusted courier networks, delivery is only available on weekdays.
Delivery & Lead Time
Current lead time: Approximately 2–3 weeks
We ship Nationwide across the UK using trusted courier networks, delivery is only available on weekdays.
Installation Guidance
Solid oak is a natural, structural timber and should be installed correctly to ensure long-term stability and performance.
Acclimatisation
Before installation, we recommend allowing your oak window sill to acclimatise in the room where it will be fitted for several days. This allows the timber to adjust to the ambient temperature and humidity levels.
- Store flat
- Keep away from direct heat sources
- Do not lean upright against a wall
Supporting the Weight
Oak window sills are solid and heavy. Proper support is essential.
- Ensure the sill is fully supported across its width
- Use appropriate brackets or battens where required
- Avoid leaving large unsupported spans
For installations above radiators, allow airflow to prevent excessive heat build-up beneath the timber.
Fixing Advice
- Secure using suitable fixings into masonry or framing
- Avoid over-tightening screws
- Always allow for natural expansion and contraction
We recommend fixing the sill close to the delivery date to minimise movement prior to installation.
If you are unsure, consult a qualified carpenter or joiner.If you are unsure, consult a qualified carpenter or joiner.
Installation Guidance
Solid oak is a natural, structural timber and should be installed correctly to ensure long-term stability and performance.
Acclimatisation
Before installation, we recommend allowing your oak window sill to acclimatise in the room where it will be fitted for several days. This allows the timber to adjust to the ambient temperature and humidity levels.
- Store flat
- Keep away from direct heat sources
- Do not lean upright against a wall
Supporting the Weight
Oak window sills are solid and heavy. Proper support is essential.
- Ensure the sill is fully supported across its width
- Use appropriate brackets or battens where required
- Avoid leaving large unsupported spans
For installations above radiators, allow airflow to prevent excessive heat build-up beneath the timber.
Fixing Advice
- Secure using suitable fixings into masonry or framing
- Avoid over-tightening screws
- Always allow for natural expansion and contraction
We recommend fixing the sill close to the delivery date to minimise movement prior to installation.
If you are unsure, consult a qualified carpenter or joiner.If you are unsure, consult a qualified carpenter or joiner.
Timber Variation & Natural Characteristics
Oak is a natural material, and every board is unique. No two window sills will ever look identical — and that’s part of the beauty.
Colour variation
Solid oak can vary in tone from light golden hues to deeper honey shades. Over time, exposure to light will naturally mellow and deepen the colour. This is not a defect — it is a natural characteristic of genuine solid oak.
Grain and knots
You may see natural knots, grain variation, small checks or character markings, and subtle colour shifts. These features add authenticity and character to your window sill.
Joined boards (for wider widths)
For widths generally over 150mm+, boards may be professionally joined to achieve the required depth. This is done to prevent movement / cupping within the board. We carefully match grain and tone to ensure a seamless, natural appearance. All joints are structurally secure and finished to the same high standard.
Natural movement
As a natural timber product, oak may expand or contract slightly depending on environmental conditions. Correct installation and acclimatisation will minimise movement.
Timber Variation & Natural Characteristics
Oak is a natural material, and every board is unique. No two window sills will ever look identical — and that’s part of the beauty.
Colour variation
Solid oak can vary in tone from light golden hues to deeper honey shades. Over time, exposure to light will naturally mellow and deepen the colour. This is not a defect — it is a natural characteristic of genuine solid oak.
Grain and knots
You may see natural knots, grain variation, small checks or character markings, and subtle colour shifts. These features add authenticity and character to your window sill.
Joined boards (for wider widths)
For widths generally over 150mm+, boards may be professionally joined to achieve the required depth. This is done to prevent movement / cupping within the board. We carefully match grain and tone to ensure a seamless, natural appearance. All joints are structurally secure and finished to the same high standard.
Natural movement
As a natural timber product, oak may expand or contract slightly depending on environmental conditions. Correct installation and acclimatisation will minimise movement.
Frequently Asked Questions
Are your window sills solid oak?
Yes. All of our window sills are manufactured from solid kiln-dried European oak. We do not use veneer or MDF-wrapped products.
Can you make them to my exact size?
Yes. Every window sill is cut precisely to the millimetre to match your measurements.
What thickness should I choose?
This depends on the look you want and the size of the opening. Thicker boards provide a more substantial, architectural feel and are ideal for larger windows.
Can I install an oak window sill / shelf above a radiator?
Yes, provided adequate airflow is maintained and the sill is properly supported. Oak is durable, but excessive heat build-up should be avoided.
Do the boards come pre-finished?
Boards are supplied planed and sanded to a fine finish, ready for oiling, staining or sealing to suit your interior.
How long is the lead time?
Current lead time is approximately 2–3 weeks from order completion.
Will my board look exactly like the photos?
Each board is unique due to natural grain and colour variation. While the quality and finish are consistent, no two pieces will be identical.
Frequently Asked Questions
Are your window sills solid oak?
Yes. All of our window sills are manufactured from solid kiln-dried European oak. We do not use veneer or MDF-wrapped products.
Can you make them to my exact size?
Yes. Every window sill is cut precisely to the millimetre to match your measurements.
What thickness should I choose?
This depends on the look you want and the size of the opening. Thicker boards provide a more substantial, architectural feel and are ideal for larger windows.
Can I install an oak window sill / shelf above a radiator?
Yes, provided adequate airflow is maintained and the sill is properly supported. Oak is durable, but excessive heat build-up should be avoided.
Do the boards come pre-finished?
Boards are supplied planed and sanded to a fine finish, ready for oiling, staining or sealing to suit your interior.
How long is the lead time?
Current lead time is approximately 2–3 weeks from order completion.
Will my board look exactly like the photos?
Each board is unique due to natural grain and colour variation. While the quality and finish are consistent, no two pieces will be identical.
At Celtic Timber, sustainability is at the heart of everything we do. We source our timber from sustainably sourced certified forests, ensuring responsible management and protection of natural resources.
We also actively contribute to reforestation and rewilding projects across the UK, planting over 12,000 trees on our own land. By choosing our products, you’re supporting a company dedicated to reducing environmental impact and preserving the planet for future generations.
At Celtic Timber, sustainability is at the heart of everything we do. We source our timber from sustainably sourced certified forests, ensuring responsible management and protection of natural resources.
We also actively contribute to reforestation and rewilding projects across the UK, planting over 12,000 trees on our own land. By choosing our products, you’re supporting a company dedicated to reducing environmental impact and preserving the planet for future generations.
Returns & Peace of Mind
We stand by the quality of our products and want you to order with confidence.
We offer a 30-day returns policy on all non-bespoke items. If for any reason you’re not completely satisfied, please contact us within 30 days of receiving your order and we’ll be happy to assist.
If your item arrives damaged or incorrect, let us know as soon as possible and we’ll arrange a replacement or agree an appropriate resolution quickly and fairly.
To qualify for a refund, items must be returned unused and in their original packaging.
Return shipping costs are the responsibility of the customer, except where the return is due to damage in transit or an error on our part.
For bespoke or made-to-measure items, please note that these are manufactured specifically to your dimensions and are therefore non-returnable unless faulty.
Returns & Peace of Mind
We stand by the quality of our products and want you to order with confidence.
We offer a 30-day returns policy on all non-bespoke items. If for any reason you’re not completely satisfied, please contact us within 30 days of receiving your order and we’ll be happy to assist.
If your item arrives damaged or incorrect, let us know as soon as possible and we’ll arrange a replacement or agree an appropriate resolution quickly and fairly.
To qualify for a refund, items must be returned unused and in their original packaging.
Return shipping costs are the responsibility of the customer, except where the return is due to damage in transit or an error on our part.
For bespoke or made-to-measure items, please note that these are manufactured specifically to your dimensions and are therefore non-returnable unless faulty.
SOLID EUROPEAN OAK
Air-dried solid European oak, carefully selected for beautiful natural grain and character. No veneers or laminates — just genuine oak that will last for generations.
HANDCRAFTED IN PEMBROKESHIRE
Each beam is individually machined, sanded and finished in our Pembrokeshire workshop by experienced craftsmen to ensure a clean, premium finish ready for installation.
READY TO INSTALL
Every beam includes the hidden fixing brackets and protective oil finish. Designed for straightforward installation with everything you need supplied.
Bespoke Solid Oak Window Sills – Crafted to Your Exact Size
Our bespoke solid oak window sills are crafted from premium kiln-dried European oak and made to measure for your project. Whether you're renovating a traditional property, installing new windows or completing a modern interior, a genuine solid oak window sill adds warmth, strength and timeless character.
Unlike mass-produced alternatives, each sill is cut precisely to your required dimensions, giving you complete flexibility for depth, length and thickness. The result is a perfectly fitted oak sill that enhances both the appearance and durability of your window space.
For over 20 years Celtic Timber has specialised in bespoke oak joinery, supplying solid oak beams, shelves, mantels and window sills to homeowners, tradespeople and businesses across the UK. Our experience, attention to detail and high-quality timber have made us one of the most trusted oak suppliers in the country.
All of our oak window sills are carefully machined and finished in our Pembrokeshire workshop, with optional oil finishes available to enhance the natural oak grain while protecting the timber for years to come.
Looking for something bespoke?
Bring your ideas to life - Head over to our bespoke order page
A
We are very pleased with the quality of our new window sills. Thank you!
M
I have ordered a standard 55cm by 22cm oak window sill and couldn't be happier. As my window sill wasn't standard I had to do some cutting and sanding but the end product was great and the piece of oak absolutely beautiful.
S
Beautiful solid oak window sill delivered efficiently and packaged very well
C
Fantastic customer service and a stunning piece of wood. It was cut to my specified bespoke size and delivery was within the 2 week window and well protected. Would purchase again from this company and recommend to others.
H
Fabulous quality of the wood, ready to seal didn’t need any extra preparation.
Service and delivery great - Would highly recommend.
S
Delivery was as promised, lead times met and quality as expected, dimensions of custom cut were spot on as requested. Would not think twice to use again.
With using same oil as the worktop, the match was perfect.
H
I recently purchased two custom size windowsills for my new kitchen. They arrived within a week, cut exactly to size requested and the wood is beautiful. I have waxed them today and it really brought out the grain. They look stunning and have been the finishing touch to my kitchen. I am truly delighted with the product, the customer service and the speed of delivery. Thank you. Will be buying for the rest of the house very soon.
C
Very happy with my purchase! The builders of our house didn't bother installing a windowsill to our downstairs loo and this oak window sill was a very easy solution to the problem. The oak is exactly the size I ordered and is amazing quality. I'll be ordering another for a larger window soon!
(I opted for the 34mm thickness, waney edge and pure oil)
W
Fantastic oak window sill! We used it to replace the mantlepiece on a plain white fireplace, and it looks amazing! Also, really quick delivery for a custom sized piece, excellent company to deal with. Many thanks.
T
Beautiful product, great that it came with the oil to finish.
J
Really nice solid oak window sill tops had these cut to size i just notched them an used Danish oil two coats come up beautifully highly recommended celtic timer
A
Really pleased with the sill.
L
Extremely happy with my purchase from Celtic Timber. Any queries I had were dealt with quickly. Lovely service from them from start to finish. Definitely recommend. Thank you 😊
N
Expensive but very nice and well prepared
A
Came as described no issue at all, quality of the packaging was amazing. Will order all my oak products from here in future.
A
We have now replaced 7 windowsills with oak from Celtic timber and they really improve the look of the house. The quality is excellent.
J
Cut cleanly and neatly, lovely oak, very well packaged.
I
5 window cills ordered. Arrived within timescale provided. Very good quality and, because the sizes were spot on, fitting was easy. Would definitely use again and would recommend to others, thank you.
J
Amazing and so beautifully finished
M
The oak piece I bought for a window sill was good and straight with fully rounded detail to three sides, as described within the ad. Measurements were spot on also.
The wood was very well wrapped with thin foam sheeting and plenty of tape.
Delivery timings was accurate, but do wonder whether the item had been dropped in transit - packaging whilst intact, seemed to have been imprinted /stuck to one side edge. No problem a piece of fine sandpaper couldn't fix
Something I didn't notice until well into fitting, was a crack from said edge for about 15". It's wood - cracks occur, so by the time I have fully varnished it and fitted it properly, it won't show.
Overall very happy, and daughter is now looking to use same supplier when she does her bathroom out.
Thank you Celtic Timber
S
So pleased with the service and quality of my product, thank you so much. Highly recommend.
M
I'm very happy with my experience with Celtic Timber. I ordered 3 window sills at different times and the sevice was excellent. They offer a range of options to customise, making it easy to find exactly what I wanted. Customer service is outstanding, with quick responses. There was an error with one of the sills (not made as per my requirement) and they quickly arranged to send a replacement.
C
Ordered three oak shelves to match an existing one.
What came is exactly what I wanted, with exact measurements and lovely quality wood.
Only problem was trying to track order.
M
Lovely piece of oak to sit under my electric stove just what i wanted. Thank you for another excellent piece of wood
R
This is the 3rd order we have had, all the sill boards have been great quality and have looked amazing in our home.
R
Our oak window sill arrived well wrapped and in good time. I opted to oil it myself and that was really simple to do. It looks fabulous in place!
