French Windows
Elegant, light-filled, and timeless
French windows have graced British homes since the 17th century, when the influence of Italian Renaissance architecture reached France and gave rise to a new way of thinking about the wall between inside and outside. Originally crafted in timber with individual panes of glass divided by slender glazing bars, the French window was essentially a large window that could also serve as a door, flooding rooms with natural light and opening directly onto gardens, courtyards, and balconies. Today, the principle is unchanged. Modern French windows deliver the same elegant proportions and seamless connection between indoors and out that made them desirable in the first place, now combined with double and triple glazing, multi-point locking, and slim contemporary profiles in a choice of aluminium, timber, and composite.
What are French windows?
A French window is a paired window that opens from the centre, with two sashes hinged at the sides and opening outward, or sometimes inward, without a central mullion dividing the glass. The absence of a central bar is the defining characteristic that sets French windows apart from a standard double casement – the full-width opening created when both sashes swing open is unobstructed from top to bottom, giving maximum ventilation and a wide, clear view.
In the UK market, French windows and French doors are closely related and often used interchangeably. The distinction lies primarily in height and floor relationship: a French window typically sits above floor level like a conventional window, whilst a French door extends to floor level and can be walked through as a door. On rear elevations opening onto gardens, terraces, and patios, the two terms describe the same architectural intention – a large, paired, outward-opening glazed element that connects the interior to the outside.
A brief history of French windows in London
French windows arrived in England in the 17th century, carried over from France where Renaissance architects had developed the style from classical Italian and Roman influences. Their appeal was immediately practical as well as aesthetic – in an era before electric lighting, the large glazed area dramatically increased natural light in principal rooms, whilst the outward-opening paired sashes created a generous opening onto gardens, courtyards and terraces.
By the Georgian and Regency periods, French windows featured regularly in the grander London townhouses and country villas, particularly on garden elevations and opening onto balconies and terraces, where the connection to the outside was a mark of refinement. In contemporary London architecture, they remain a popular choice for rear extensions, garden rooms, and kitchen-dining spaces where the connection to the outdoor living area is a design priority.
Types of French windows
We work with leading manufacturers and brands to supply a full range of French window configurations for London homes:
The brands we work with
Benefits of French windows
French windows offer a distinct combination of aesthetic and practical advantages that have kept them relevant in London architecture across four centuries:
When French windows are the right choice
French windows suit a wide range of situations across London properties:
Rear rooms opening onto a garden or terrace – the most natural position. A ground-floor kitchen, dining room or sitting room gains enormously from a pair of French windows opening directly onto the garden.
Kitchen-dining extensions – where the architect or homeowner wants a connection to the outside that is more intimate and characterful than a wide sliding or bifold system.
Period properties – where the traditional paired glazed opening suits the architectural character of the building far better than a sliding patio door or bifold.
First-floor rooms with Juliet balconies – full-height French windows paired with a glass or metal balustrade bring light and outside air into first-floor bedrooms and studies without requiring a full balcony structure.
Conservation areas – French windows with glazing bars and timber or composite frames are widely accepted in conservation areas and for listed buildings where the original window type was a paired casement or French light.
Rooms where an outward-opening casement already suits the elevation – French windows share the same outward-opening mechanism as a casement, so they are a natural upgrade where more ventilation and a larger opening are wanted.
Finishes, hardware and security
Finishes & colours
French windows are available across a full RAL colour range in all materials. Dual colour finishes are a popular choice for London period properties – a classic white, cream or off-white interior alongside anthracite grey, sage green, heritage black or any RAL shade externally. Timber interiors can be lacquered to show the natural grain or painted to complement the interior scheme.
Glazing options
All French windows we supply are available with:
Double glazing – the standard specification for most London homes, meeting current Part L building regulation requirements and comfortably covering double glazing windows near me searches.
Triple glazing – triple glazed window units for positions facing busy roads, rail lines or where maximum thermal performance is required.
Acoustic glass – laminated acoustic units that reduce outside noise in urban and high-traffic locations – particularly relevant for London rear gardens facing railway lines or busy streets.
Hardware & security
French windows are fitted with multi-point locking systems engaging at multiple points around both sashes. Traditional hardware options include espagnolette bolts, monkey tail handles and flush bolts for the secondary sash, whilst contemporary systems use ergonomic bar handles with concealed multi-point locking. All French windows we supply can be specified to PAS 24 security standards. Additional options include key-lockable handles and night vent positions.
FAQ
Both open from the centre on paired side hinges and create a wide unobstructed opening. The key distinction is height and floor relationship. French windows sit above floor level like a conventional window, whilst French doors extend to floor level and can be walked through. In practice, on rear elevations opening onto gardens and terraces, the two terms are often used interchangeably.
Yes, in many cases. French windows with glazing bars and timber or composite frames with period-accurate profiles are widely accepted by planning authorities in London conservation areas and for listed buildings. We recommend checking with your local planning authority before proceeding.
Yes. Any glazing below 800mm from floor level must be toughened or laminated safety glass under Part K of the building regulations. For full-height French windows extending to floor level, the entire glazed area must be specified as safety glass throughout.
Yes, when correctly specified. Modern French windows use multi-point locking systems that secure both sashes at multiple points around the frame. All French windows we supply can be specified to PAS 24 security standards. The secondary sash is typically secured with flush bolts at top and bottom in addition to the main locking handle.
Yes. Modern French windows with thermally broken frames and double or triple glazing comfortably meet current building regulation requirements for thermal performance. Inward-opening configurations can achieve particularly good airtightness as the sashes compress against the frame seal when closed.
Costs vary depending on material, size, glazing and specification. Timber French windows sit at the premium end, whilst aluminium offers a competitive price point for contemporary designs. Contact us for a tailored windows installation price.