What Are Cottage Windows? Styles, Materials & Costs

The cottage window style evolved from practical necessity in rural English building. From the 17th century onwards, cottages and farmhouses used simple casement windows with small panes of glass held in place by lead cames (strips) or wooden glazing bars. As glass manufacturing improved and became more affordable in the 18th and 19th centuries, the number of panes in each window decreased, eventually settling on the characteristic two-over-two or one-over-one layout divided by a single horizontal bar. The horizontal bar served both structural and practical purposes: it stiffened the window frame, allowed the upper section to be fixed while the lower section opened, and created a visual division that suited the modest proportions of cottage architecture. Unlike the Georgian sash window, which was a product of fashionable urban architecture, the cottage casement was a vernacular design that evolved organically in rural communities, which is why it has such an authentic, unpretentious character.

Timber cottage windows are the most authentic choice, using softwood (from approximately £500 per window) or hardwood (from approximately £800 per window). Timber allows for traditional moulding profiles, slim glazing bars, and a natural appearance that suits period properties and conservation areas. Modern factory-finished timber windows with microporous paint systems require less maintenance than traditional hand-painted windows. uPVC cottage-style windows offer the traditional appearance at a lower price (from approximately £350 per window) with virtually no maintenance. Modern uPVC profiles can closely replicate the proportions and moulding details of timber cottage windows, including mechanical joint options that eliminate the visible welded corner associated with older uPVC windows. Woodgrain foils in golden oak, rosewood, and other finishes add to the authentic appearance. Aluminium cottage-style windows provide slim frame profiles and a contemporary interpretation of the traditional style, priced from approximately £600 per window. They are particularly suited to modern barn conversions where a blend of traditional and industrial aesthetics is desired.

Standard double glazing with low-e glass and argon gas fill is appropriate for most cottage window replacements, achieving U-values of 1.2-1.4 W/m²K. For properties in conservation areas where slimmer sealed units are required, slim-profile double glazing (14-16mm total thickness compared with the standard 24-28mm) is available, though with slightly reduced thermal performance (U-values of approximately 1.6-1.8 W/m²K). Leaded-light cottage windows can be double-glazed using sealed units with internal lead strip decoration that replicates the appearance of traditional lead cames without compromising thermal performance. This is a popular option for achieving an authentic lead-light appearance with modern insulation. For the most authentic restoration, individual glazed panes with traditional linseed oil putty are still available, though single glazing is only appropriate for listed buildings where planning restrictions prevent double glazing. Decorative glass options include obscure glass for bathrooms, textured glass for privacy, and heritage glass with subtle distortions that replicate the character of antique glass.

Modern cottage-style windows offer excellent energy efficiency regardless of their traditional appearance. Double-glazed cottage windows with low-e glass, argon gas, and warm-edge spacers achieve U-values of 1.2-1.4 W/m²K, meeting Building Regulations requirements. The horizontal glazing bar has minimal impact on thermal performance when it is a plant-on bar applied to a single sealed unit. True glazing bars that physically divide the glass into separate panes create a slightly less efficient window due to the additional sealant junctions, but the difference is modest. Triple glazing is available for cottage-style windows and achieves U-values of 0.8-1.0 W/m²K, though the additional unit thickness and weight should be discussed with your supplier to ensure compatibility with the cottage window profile and hardware. Trickle vents are typically required under Building Regulations for replacement windows. On cottage windows, they can be fitted into the frame head and finished to match the frame colour, maintaining the traditional appearance.