Composite windows – the best of timber and aluminium in one window
Composite windows combine a natural timber interior with a durable, low-maintenance aluminium exterior to deliver a window that performs exceptionally well and looks beautiful from both sides. They are increasingly specified across London for renovations, extensions, and new builds where homeowners want slim sightlines, outstanding thermal performance, and a warm, characterful interior finish.
Why choose composite windows?
Composite windows, also known as alu-clad or timber aluminium windows, offer a unique combination of properties that neither pure timber nor pure aluminium can match on their own.
How composite windows are made
A composite window frame has two distinct layers working together. The interior is timber – a natural insulator that adds warmth, reduces thermal bridging and gives a characterful finish inside the home. The exterior is clad in powder-coated aluminium, which is highly resistant to weather, corrosion and UV degradation without needing periodic repainting.
This construction means composite windows consistently achieve better thermal performance than standard aluminium windows, whilst requiring far less maintenance than a traditional timber window – making them a sound long-term investment for London homeowners and architects alike.
Composite window styles
We work with leading composite window manufacturers to supply a full range of styles for London homes. Whether you are upgrading a period terrace, renovating an Edwardian semi, or designing a contemporary extension, we help you select the right style, profile, and glazing for the project.
Side-hinged casement window styles in flush or rebated profiles, suited to period and contemporary homes alike.
Sash windows in timber aluminium construction, replicating traditional vertical sliding profiles with modern thermal performance.
Classic bay windows with aluminium-clad exteriors that stand up to the London climate whilst maintaining a warm interior finish.
Dual-action tilt and turn windows for safe ventilation and easy cleaning, particularly popular in upper-floor positions.
Timber aluminium French windows with a slim aluminium exterior and warm timber interior, ideal for garden rooms, rear extensions, and glazed walls opening onto outdoor spaces.
Shaped windows, gable windows, top hung window units, and fixed light windows – bespoke options for architectural features, stairwells, and vaulted spaces.
Looking for something else? Please get in touch with us. We work with a wide range of timber window styles and manufacturers.
Finishes, hardware and security
Finishes & colours
The aluminium exterior is factory powder-coated and available across a full RAL colour range, including gloss, matt, satin and textured finishes. The timber interior can be lacquered to show the natural wood grain or painted in any RAL colour to complement your interior. Dual colour finishes – with a different shade inside and out – are a popular choice for London homes, keeping a classic white or natural timber tone inside whilst using a bold or neutral colour on the exterior.
Glazing options
Double glazing
The standard choice for most London homes and the most common starting point for double glazing windows near me searches. Composite double glazed units provide excellent energy efficiency and comfortably meet current building regulations for thermal performance.
Triple glazing
Triple glazed window units are available for positions where extra insulation or noise reduction is required – near busy roads, rail lines, or flight paths. Many composite systems achieve outstanding U-values with triple glazing, making them well-suited to low-energy and Passivhaus projects.
Acoustic glass
Laminated acoustic units reduce outside noise in urban and high-traffic locations, helping rooms feel calmer and more comfortable without altering the window’s appearance.
Hardware & security
Composite windows are fitted with high-quality multi-point locking systems and ironmongery chosen to suit the style of the property. All windows can be specified to PAS 24 security standards, and additional night vent restrictors and child safety locks are available on request.
Windows for conservation areas and historic buildings
Composite windows are increasingly accepted in conservation areas and sensitive heritage settings, particularly where slim sightlines and timber-like interior profiles can be demonstrated to planning authorities. Working with specialist composite manufacturers, we can specify profiles and glazing bars that replicate original window details, and supply the technical documentation required to support planning applications and listed building consent submissions. This makes composite windows a practical and long-lasting alternative to pure timber for house window replacement projects in London’s many conservation areas.
The brands we work with
Explore other window materials
Composite windows are one of several premium options we supply. Depending on the style of your property and your priorities, you may also want to consider:
FAQ
Quality composite windows are built for a long service life – typically 40 years or more with minimal maintenance. The aluminium exterior protects the timber core from weathering, meaning the frame retains its appearance and performance for decades. All composite windows we supply come with a manufacturer's warranty for added peace of mind.
The aluminium exterior requires very little upkeep – an occasional clean is usually all that is needed. The timber interior may benefit from a periodic wipe-down with a suitable product, but there is no need for regular repainting or sealing as with a traditional timber window.
Yes, in many cases. Composite windows with timber-like profiles, slim sightlines and heritage glazing options are increasingly accepted by local planning authorities.
Yes. The timber core provides excellent natural insulation, and composite systems consistently achieve strong U-values. With triple glazed window units, composite windows can reach U-values suitable for Passivhaus and low-energy builds.
Double glazing window costs for composite windows vary depending on the brand, system, size, style and glazing specification. As a premium product, composite windows sit above standard aluminium or uPVC in price, though the long service life and low maintenance make them a cost-effective long-term investment. Contact us for a tailored windows installation price.