• Made to order in our Kent workshop
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Timber sliding sash windows in a white rendered townhouse, made by Spittlywood
UK Delivery

Nationwide

UK Delivery
Lead Times

Lead Times

6 – 8 Weeks
South East Install

Installation

South East UK
Finance

Finance

From 10.9% APR

Made to measure

Bespoke Sash Windows

Sash windows bring timeless elegance and refined character to both period and contemporary homes. At Spittlywood, we design and manufacture bespoke timber sash windows that blend traditional styling with modern-day performance offering smooth operation, energy efficiency and long‑lasting reliability. Whether you are restoring a heritage property or upgrading a family home, our sash windows enhance both the interior and exterior with their unmistakable charm.

Each window is crafted in our Kent workshop using a combination of state‑of‑the‑art technology and expert joinery techniques. This ensures every sash window achieves the perfect balance of authenticity, functionality and security. With advanced energy‑efficient glazing, robust locking options and durable materials, our sash windows contribute to a warm, comfortable and secure home throughout the year.

At a glance

Timber

Accoya or Red Grandis

Glazing

Double, triple or vacuum

U-values

From 0.7 W/m²K

Security

PAS 24, Secured by Design

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Brochure

Download our brochure

View our range of bespoke timber windows & doors.

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Accredited and certified

Kent Trading Standards
Fensa
PAS24
UKCA
Secured By Design
FSC
ISO 9001
ISO 50001
ISO 14001

Sash Windows

Our Work

Sash Windows 1
Sash Windows 2
Sash Windows 3
Sash Windows 4
Sash Windows 5
Sash Windows 6
Sash Windows Gallery (3)
Sash Windows Gallery (4)
Sash Windows Gallery (5)
Sash Windows Gallery (6)
Sash Windows Gallery (2)
White timber sash window in a weatherboarded house, made by Spittlywood
Sash Windows Gallery (7)

Specification

Make it yours

Timber

Recommended Timber
For the best balance of durability, stability and aesthetics, we recommend:

Accoya

Accoya is a high-performance modified timber that offers industry-leading stability and durability. It does not shrink or swell, ensuring windows and doors operate smoothly in every season. This stability prevents paint from cracking, meaning finishes last significantly longer. It is ideal for the British weather and is guaranteed against rot for 50 years.

Red Grandis

Red Grandis is a durable hardwood known for its consistent grain and uniform appearance. It provides an excellent, smooth surface for both paint and stains, making it a popular choice for premium joinery. Sourced from sustainable plantations, it offers a high-quality, stable, and ethically sound alternative to traditional hardwoods.

Finishes

Factory Finishes
Our finishes are done in house and we offer the following:

Opaque finishes

These coatings provide a flawless, uniform look in any shade. They offer maximum protection by blocking UV rays and sealing out moisture to prevent fading and timber movement.

Translucent finishes

Designed to showcase the wood’s natural grain and texture, these finishes provide a warm, organic aesthetic while maintaining a durable, weather-resistant shield.

RAL and custom colours

Choose from 147 standard colours or opt for our colour-matching service to RAL, British Standard, or NCS charts for a truly bespoke finish.

Factory finished

Every item is coated in a controlled factory environment before delivery. This ensures even coverage and superior adhesion for a professional, long-lasting result that on-site painting can’t match.

Glazing

Sash Glazing
We offer the following glazing options:

Standard double glazing

Unless a client requests an alternative specification, our joinery is typically supplied with 24 mm double-glazed units filled with Argon gas. In a unit of this thickness, alternative gases do not offer any meaningful improvement to thermal performance, so Argon represents the most effective and sensible choice in terms of insulation, reliability, and value.

Slim heritage units

For heritage properties or conservation areas with strict planning requirements, we offer slim double-glazed units. These are filled with Krypton gas, which performs more effectively than Argon in thinner cavities. This allows us to maintain slender, authentic profiles without sacrificing the thermal performance needed for a comfortable living environment.

Specialist and triple glazing

We offer a range of advanced glazing solutions for specific project needs. This includes triple glazing for superior acoustic and thermal insulation, as well as cutting-edge vacuum glazing. For those seeking an authentic period look, we can provide double-glazed units with drawn glass to recreate the subtle, classic distortions found in historic windows.

Ironmongery

We supply premium Hardwick ironmongery to provide the perfect finishing touch to your joinery. These high-quality fittings are crafted from solid brass, ensuring they feel substantial and operate smoothly. Available in a variety of styles, from the Heritage range to sleek contemporary designs.

Finish
Hardwick TB Reeded Narrow locking claw fastener
Reeded Narrow Locking Claw FastenerHardwick · TB
Hardwick TB Narrow Locking fitch fastener
Narrow Locking Fitch FastenerHardwick · TB
Hardwick TB Modern Non-locking brighton fastener
Modern Non-Locking Brighton FastenerHardwick · TB
Hardwick TB Ball knob locking claw fastener
Ball Knob Locking Claw FastenerHardwick · TB
Hardwick TB 45mm wheel ball bearing pulley square
45mm Wheel Ball Bearing Pulley SquareHardwick · TB
Hardwick TB 45mm wheel ball bearing pulley radius
45mm Wheel Ball Bearing Pulley RadiusHardwick · TB
Hardwick TB 19mm roller stop set
19mm Roller Stop SetHardwick · TB
Hardwick TB 19mm flush stop set
19mm Flush Stop SetHardwick · TB
Hardwick TB 120mm sash handle
120mm Sash HandleHardwick · TB
Hardwick TB 1090 sash lift
1090 Sash LiftHardwick · TB

Technical

Head and jambs

102mm x 164mm

Cill

68mm x 164mm

Mullion

141mm x 198mm

Sash top rails and stiles

56mm x 57mm

Sash bottom rail

90mm x 57mm

Sash profile

Ovolo or Lambs Tongue

Cill projection

Flush, 35mm, 60mm, 85mm or 110mm

Trickle vents

Concealed through head, 4600EA

U-values, W/m²K (lower is better)

Double glazing

1.2

Triple glazing

0.9

Vacuum glazing

0.7

What you can expect

Why choose our sash windows

Premium quality

All our products are meticulously crafted by seasoned joiners using state-of-the-art machinery, computer-aided precision and expertly finished by hand.

Sustainable

We are committed to providing sustainable options using eco-friendly materials and processes that are proven to support the environment.

Energy efficiency

U-values from 1.2 W/m²K for double glazing, improving with triple glazing, and lower again with vacuum glass hybrid units.

Multiple choice

We offer a wide range of materials, hardware and colours including slim frames and single, double, triple and vacuum glazing.

Bespoke designs

Every design is unique and handcrafted to your preference, specification and thoughtfully chosen decorative elements.

Enhanced security

Our products are PAS 24 accredited and provide tested locking systems created with durable materials that protect your family.

Working with us

Heritage, trade and installation

Listed and heritage

Arched oak window in a stone watermill beside a waterfall, made by Spittlywood

Heritage and conservation

Listed and Heritage Properties

We have extensive experience crafting timber sash windows for listed buildings and heritage homes. Our team understands conservation requirements and produces joinery that respects the original architectural details. We can:

Replicate existing mouldings and profiles

Match heritage proportions and detailing

Meet conservation and planning guidance

Supply sections and elevations for consent

Materials

Timber sash window and green stable door on a brick cottage, made by Spittlywood

Materials

Sustainable materials

We manufacture our sash windows using premium, sustainably sourced timbers, including hardwoods, softwoods and Accoya. These materials offer exceptional durability, weather resistance and long service life. Accoya and Red Grandis are among our most recommended choices thanks to their outstanding stability and low-maintenance performance.

The combination of quality timber and proven manufacturing techniques ensures that each sash window remains dependable for decades, with minimal maintenance required to stay looking its best.

Bespoke joinery design

Expert craftsmanship and installation

Sustainable timber and finishes

Trade partners

The Spittlywood joinery workshop

Team up with Spittlywood

Become a Trade Partner

We build trade partnerships with trusted professionals to deliver the best quality products and services.

Monthly DWG files

Part Q compliant blueprints

Trade pricing

Competitive trade account rates

Specification advice

Help choosing the right product

Installation advice

Support from our team

Account manager

Dedicated, after your first order

White-label brochure

To share with your customers

Find out more

Delivery and installation

White timber sash window in a weatherboarded house, made by Spittlywood

Across the South East

Installation across the South East

We deliver across the UK, with installation available throughout Kent, London and the South East. Whether you are a homeowner, architect, builder or developer, our team is on hand to help with technical specifications, planning requirements and design choices.

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FAQs

Sash

Still have questions?

01233 730816

[email protected]

Heritage and planning

Do you have experience working with listed buildings?

Yes, Spittlywood has years of experience manufacturing and fitting timber sash windows for listed and heritage properties. We understand conservation requirements and ensure every design is sympathetic to the building’s character.

Can you match existing sash windows for period or listed homes?

Absolutely. We specialise in heritage and conservation joinery, replicating original profiles, mouldings, and detailing to satisfy planning and conservation standards.

Can you provide section drawings for planning permissions?

Yes, we can provide detailed section drawings, elevations, and specifications to support your planning or listed building consent application.

Timber and finish

What timbers do you recommend for sash windows?

We recommend Accoya and Red Grandis (engineered hardwood). Both offer outstanding durability, stability, and weather resistance. Accoya provides exceptional longevity with minimal maintenance, while Red Grandis offers the warmth and beauty of traditional hardwood.

Can sash windows be painted or stained?

Yes. All windows are factory-finished in your chosen paint or stain using high-quality microporous coatings that protect the timber and maintain a flawless finish.

Do you supply bare wood items?

Yes we can supply sash windows as bare timber, ready for on-site finishing or painting. This allows builders or specialist decorators to apply their preferred finishes.

Security and glazing

Are your sash windows secure and weather-resistant?

Yes. All sash windows are built to PAS 24 standards for enhanced security and BS 6375 for weather performance, providing long-term reliability and peace of mind.

What is PAS 24 and why is it important?

PAS 24 is a British standard for security, confirming that your windows have been tested to resist forced entry.

What type of glazing do you use?

We use high-performance double and triple glazing, sourced from reputable local suppliers in Ashford, Kent. These units enhance energy efficiency, reduce noise, and improve security. For heritage projects, we offer Thinlite units with narrow cavities to preserve traditional aesthetics. Additionally, we provide toughened and laminated glass for safety and fire-resistant glass where required.

Do you offer triple glazing for sash windows?

Yes, triple glazing is available to enhance thermal performance and energy efficiency.

Supply and lead times

Do you supply and fit sash windows?

Yes, we offer both supply-only and full installation services. We’re also happy to work alongside builders, architects or main contractors.

How long does it take to make bespoke sash windows?

Lead times typically range from 6–12 weeks, depending on design and finish requirements.

Our range

Windows and doors

All products

Next steps

Ready to start your project?

Send us your sizes, or your drawings, and we will come back with an estimate. Everything is made to order in our Kent workshop, with a lead time of six to eight weeks.

Request an estimate
Download the brochure