Lipped Timber Casement Windows
Bespoke lipped timber casement windows
The lipped casement window, frequently referred to as a storm-proof casement, remains one of the most widely specified window styles across the UK. It is instantly recognizable by a sash that overlaps the external frame to provide enhanced protection against the elements.
Our timber lipped casements are engineered with a refined, decorative edge on the opening sash to soften their profile lines. To ensure a perfect architectural match, they are available in two distinct profiles: a clean, minimalist pencil round moulding for contemporary builds, or a classic ovolo moulding to retain the character of traditional homes.
Double glazed timber windows with a 1.2 U-value
Our double-glazed wooden lipped casement windows are up to 25% better than the new Part L 2022 building regulations, with U-values starting from 1.2 W/m²K.
We also offer triple-glazed and quadruple-glazed lipped timber casement windows that are up to 50% and 70% better, with U-values starting from 0.8W/m²K and 0.6W/m2K.
Premium lipped timber casement windows
Lipped casement windows, also known as stormproof windows, are incredibly popular throughout the UK. Designed with an overlapping sash that sits proud of the frame, they offer exceptional weather protection, making them an excellent addition to both traditional and contemporary homes.
Tailored to Your Vision
Our lipped casement windows can be customized in a wide range of styles, configurations, and finishes. This flexibility allows you to design a unique window that perfectly complements your property’s architectural character.
High-Performance Insulation
Crafted from sustainably sourced timber, these windows take advantage of wood’s natural insulating properties. This premium material choice significantly reduces heat loss, lowering your energy bills and improving your home’s overall thermal efficiency.
Engineered for Longevity
We use only the highest quality materials and manufacturing techniques to ensure our lipped casement windows are robust and hard-wearing. They are built to last a lifetime, and we back that durability with a comprehensive 10-year warranty on all products.
Certified Safety and Security
Your peace of mind is built directly into the design. Our lipped casement windows are fully Secured by Design accredited and Part Q certified, providing advanced resistance against forced entry to keep your home safe and secure.
Homeowner Solutions ⟩⟩
Discover the ideal premium timber windows and doors to elevate your home renovation, extension, or self-build project. Coluxor combines exceptional craftsmanship with timeless design, allowing you to transform your vision into reality today.
Professional Solutions ⟩⟩
Discover how Coluxor’s exceptional timber windows and doors can flawlessly complement your commercial or residential trade project, regardless of scale or specification. Elevate your builds with the perfect blend of traditional craftsmanship and modern performance.
Choose lipped casement windows that don’t cost the earth
Our flush casement windows are naturally renewable, carbon neutral, and made from only sustainably sourced FSC 100% certified softwood or hardwood. Our care and attention to our timber before and during the manufacturing process ensures a 50 year+ life span, 10-year warranty, and low maintenance for life.
Totally bespoke lipped timber casement windows
We manufacture completely bespoke sizes and designs up to 5 meters in length and five lights wide. You can combine fixed and opening sashes in any configuration, utilizing traditional or heritage mouldings to match the character of your project. This design flexibility allows for the creation of striking architectural elements, including elegant oriel or bay feature windows, as well as complex geometry like curved frames and swept heads (curved plates). To achieve your desired look, you can incorporate applied 16mm, 25mm, and 35mm glazing bars to recreate timeless horizontal, cottage, Georgian, or marginal bar patterns, or divide panes with intricate arched or gothic designs. Alternatively, you can make a classic architectural statement with traditional leadwork available in diamond, square, or Queen Anne styling.
Redwood or hardwood timber windows
Every window in our collection is expertly crafted from certified, sustainably sourced engineered laminated timber. We provide the choice between premium redwood (Scots Pine) and durable hardwood (Dark Red Meranti), both backed by our identical, comprehensive warranties. While both offer exceptional performance, our hardwood features a more open grain pattern, delivering a beautifully textured aesthetic that is especially striking when finished with a timber stain.
Conservation-Grade Timber Windows
Specifically engineered for listed buildings and conservation areas, our Heritage profile flush casement windows seamlessly blend historic charm with modern performance. Available in both single and slimline double-glazing options, the 16mm slimline units feature internal glazing alongside a comprehensive drainage and ventilation system. Achieving an impressive U-value of 1.4 W/m²K and ensuring full compliance with current building regulations, they satisfy strict heritage requirements without compromising on comfort or thermal efficiency.
High performance lipped casement windows
Achieve a quieter home with advanced acoustic insulation that reduces external noise by up to 42 dB. Our windows are equipped with double glazing and warm-edge spacer bars as standard, delivering U-values from 1.3 W/m²K to ensure full compliance with current Part L Building Regulations.
To guarantee lasting quality, Coluxor casements are certified under the BlueSky high-performance window scheme, providing reliable draft-proofing and weather protection in all conditions.
Security
Your peace of mind is our priority. Coluxor timber lipped casement windows are fully Secured by Design accredited and third-party tested to comply with strict Part Q building regulations. Each window features multi-point espagnolette locking handles and is internally glazed as standard, preventing the glass panes from being removed from the outside.
For day-to-day safety and functionality, our casements are equipped with versatile easy-clean or egress friction hinges, secure night vents for protected ventilation, and built-in child safety restrictors.
Colour
Every lipped casement window is factory-finished with eco-friendly, water-based paints and stains formulated for long-term weather resistance. You can select your finish from extensive RAL Classic, RAL Design, NCS, and BS color charts, or opt for an exact match to designer palettes from Farrow & Ball, Earthborn, or Fired Earth.
With both single and dual-color options available, you have the freedom to coordinate the external frame with your property’s brickwork or rendering while matching the internal finish to your interior decor.
RAL 9016
RAL 9003
RAL 9010
RAL 9001
RAL 1015
RAL 6019
RAL 3002
RAL 3005
RAL 5014
RAL 5013
RAL 5022
RAL 6005
RAL 7032
RAL 7015
RAL 7016
RAL 7040
RAL 7035
RAL 9005
RAL 7037
RAL 7030
RAL 7024
RAL 3011
RAL 6021
BS.10.B.17
BS.10.B.15
BS.10.C.31
French Green
Parchment
London Dust
Parlour
Smoke
Linen
RAL Colour
Glazing
Glazing is a critical component of any window project, directly affecting thermal efficiency, sound insulation, and aesthetics. Our timber lipped casement windows can be specified with traditional single glazing, narrow-cavity SlimLine glazing, standard double glazing, or maximum-efficiency triple glazing. To achieve your desired architectural layout, you can incorporate applied glazing bars in widths of 16mm, 25mm, or 35mm to recreate authentic period grids or sleek modern patterns.
If external noise is a concern, we offer specialized acoustic double glazing capable of delivering sound reduction ratings between 33dB and 42dB. For bathrooms, front entrances, or overlooked elevations, a variety of obscure privacy glass patterns are available with obscurity ratings from 1 to 5, alongside striking translucent colored and opaque painted glass options to create a unique design feature.
Frosted
Reeded
Chinchilla
Delta
Stippolyte
Arctic
Cotswold
Ironmongery
Security and operation are managed via a multi-point espagnolette locking system controlled directly by the window handle. You can select from our exclusive collection of four handle designs and decorative stays, bridging the gap between classic period styling and sleek modern aesthetics.
With up to 10 different color finishes available across the range, you can perfectly coordinate your hardware with your chosen paint or stain. Follow the link below to explore our complete selection of premium window ironmongery.
Brass Bulb End Handle
Bronze Bulb End Handle
Polished Chrome Monkey Tail Handle
Rumbled Brass Bulb End Handle
Satin Chrome Handle
Stainless Steel Round Bar Handle
Black Handle
Polished Brass Handle
Polished Nickel Bulb End Handle
Rumbled Pewter Bulb End Handle
Satin Nickel Bulb End Handle
Future-Ready Timber Casements
Engineered ahead of the Future Homes Standard, Coluxor double-glazed timber windows and doors easily surpass Part L building regulations, delivering impressive U-values from 1.3 W/m²K-a 7% improvement over standard guidelines. For even greater thermal efficiency, our triple-glazed options achieve exceptional U-values starting at just 0.8 W/m²K, outperforming regulatory requirements by a remarkable 43%.
Consciously Crafted Timber Windows
Invest in eco-friendly lipped casement windows crafted exclusively from certified, responsibly sourced softwood or hardwood. Naturally renewable and carbon-neutral, our timber undergoes meticulous preparation and manufacturing to guarantee an exceptional 60-year+ lifespan. Backed by a 10-year warranty, Coluxor windows deliver enduring strength and low maintenance for a lifetime of worry-free performance.
Lipped Casement FAQs
What is the difference between a flush and a lipped casement?
Flush casement sashes sit completely level and flat within the frame for a smooth exterior finish. In contrast, lipped (or stormproof) casements feature a sash that slightly overlaps the frame’s edge.
Do flush and lipped casements differ in weather performance?
Coluxor timber flush casement windows are engineered with advanced dual weather seals to eliminate drafts and provide superior protection against the elements. Furthermore, both design options feature adjustable compression hardware, allowing you to fine-tune the seals over time to maintain an airtight, highly resilient barrier.
What hinges do your casement windows come with?
Every Coluxor casement window is equipped with high-performance, easy-clean friction hinges as standard. This specialized hardware allows the window to open wide enough for effortless cleaning from the inside, while smoothly holding the sash securely in your desired open position.
Do I need a stay on my casement windows to hold them open?
No, window stays are not required. Coluxor casement windows are engineered with built-in easy-clean or egress friction hinges that reliably hold the sash in place at any opening angle. Additionally, both our traditional lipped and flush casements feature a secure night vent position, letting you safely ventilate your home without fully opening the window.
Do you offer mock sash casement windows?
Yes, we provide mock sash configurations across multiple operating styles. You can choose from traditional side-hung or top-hung (regency casement) designs, as well as highly versatile, inward-opening Tilt & Turn window systems to perfectly suit your architectural needs.
Do I require Part Q compliance on a casement window?
Approved Document Part Q applies strictly to new dwellings. It is a mandatory requirement if you are constructing a self-build property or executing a material change of use (such as converting a barn into a home). While standard home renovations or direct window replacements are exempt, prioritizing robust security is always recommended.
At Coluxor, we build exceptional security into our products as standard. Our windows can be specified with multi-point espagnolette locking systems and Neighbourhood Watch-approved, 3-star high-security cylinders to ensure maximum protection for your home.
Why Choose Coluxor?
At Coluxor, we take great pride in providing friendly and professional service from the initial enquiry to the final order and installation. We offer expert guidance for both new construction and renovation projects, including historically significant listed properties, to ensure that your windows and doors not only meet performance standards and U values but also align with your preferred style, design, and color choices.