Original sash windows are an essential part of our heritage and a distinctive feature of numerous period houses across the UK, from cottages and terraced homes to stately mansions. The sashes themselves – that is, the opening parts – are sliding rather than hinged, as with casement windows. They usually slide vertically, hung on cords or chains and counterbalanced by metal weights housed in a box frame. 

Where homeowners appreciate these architectural antiques, they employ suitable contractors to carry out any necessary work. However in most cases, some basic maintenance and repairs should ensure the windows will provide many more years’ good service.

Related articles: How to choose windows for your period home | Door and window maintenance in old houses | maintaining and repairing leaded windows | How to repair metal windows

heritage sash windows from CaldwellThese original timber-framed Georgian bay windows have been renovated and draught-proofed by Heritage Sash Window Specialists at £245 per window, which includes new brassware

Repairing sash windows

Sashes sometimes stick because of paint accumulation or a poorly positioned or distorted stop bead (internal perimeter strip), both of which are easily resolved. In other cases, it is necessary to adjust sash weights, re-cord the sashes or trim a warped frame. Lubricating pulleys and waxing sash edges can also help.

Where necessary, specialist companies can undertake draught-proofing or more major repairs, such as cutting out and replacing sections of rotten timber. Another option with draughts and rattles is to fit a cam-action catch or sash wedges.

Excessive wear of timber components allows sashes to move too freely and causes the overlapping horizontal or “meeting” rails to settle out of level. Make sure that the running surfaces are smooth and reposition the stop beads. In severe cases, re-edging of the sashes might be required.

Regular painting helps prevent decay. Specialist sash brushes with pointed ends will help you achieve a neat finish. Sash cords also require occasional renewal.

When to replace sash windows

The installation of new sash windows in an old building may be justified where there are inappropriate existing modern windows, or when adding an extension. Avoid the indiscriminate replacement of old sashes (particularly with uPVC substitutes) and remember that old sashes can be upgraded to meet the insulation standard of double-glazed new ones. 

The Sash Window Workshop bay window in bedroomThe Sash Window Workshop specialises in the replacement of timber sash windows; it is able to replicate existing windows and has worked in many Conservation Areas, POA

Totali Sash Windows

totali sash window

Ideal for period, modern or farm style homes; Totali sash windows are fully draught sealed to eliminate the draughts and rattles so often associated with original sliding sash windows. They are also designed for the specialist needs of conservation areas throughout the UK. Discover the beauty of timber with low maintenance timber sash windows, hand finished to your specification. www.totali.uk.com

A short history 

Fashionable in England from the latter part of the 17th century, sash windows are synonymous with Georgian architecture. By the 18th century, they had superseded casement windows in all but the humblest dwellings. Sashes remained predominant for the next 200 years, frequently being inserted into earlier buildings in order to update them. 

The earliest examples were “single-hung”, whereby only one – usually the lower – sash moved. Generally of oak or pine, these windows had small panes with thick glazing bars and were set nearly flush with the outside wall face. 

By the mid-18th century, double-hung sash windows, where both sashes could move, were widely seen. The use of pine and sash boxes that were set back from the wall face also became usual, as well as larger panes and thinner glazing bars. The availability of yet larger sheets of glass led to the use of horns on windows from about 1850 to strengthen joints. Sash boxes were often also hidden behind walls by the Victorians. A variation popular in the 18th and early 19th centuries was the “Yorkshire sash”, where the sashes move sideways without weights. 

Best new sash windows

bespoke multipane window from the Original Box Sash Company on a red brick house with a red door and bay windowsBespoke multi-pane replacement sliding sashes, by The Original Box Sash Window Company, are discreetly double-glazed for this Grade II-listed property. POA (0800 169 2236)

MW-The-Old-Hall-15-sash-windowThis bespoke double-glazed box sash window from Mumford & Wood’s Conservation range is made from engineered timber, designed to prevent twisting and warping. Priced from £2,478 per window (01621 818155)

heritage box sash window on clad wall from Westbury JoineryHeritage box sash windows by Westbury Windows & Joinery are made using premium engineered larch timber finished with three coats of Westbury White paint. Complete with applied glazing bars as well as traditional locks and sash lifts, box sashes start at £3,000, depending on style

bespoke windows from Scotts of Thrapston

Besides the top casement window, all the windows in this period property are traditional ‘six over six’ sliding sashes with fixed radius-head top lights. Manufactured on a bespoke basis by Scotts of Thrapston, all are finished with microporous white paint. POA (01832 732366)

Ventrolla double-glazed sliding sash windows

Ventrolla’s double-glazed vertical sliding sash windows have accoya wood frames and a 50-year guarantee. Pricing varies depending on size and the work involved

Lomax & Wood Kensington and Chelsea range box sash window

This made-to-order double-glazed box sash window with fixed sidelights, from Lomax & Wood’s Kensington and Chelsea range, is operated with traditional cords and weights. Made from sustainably sourced timber, it costs from £1,920 (01277 353857)

Lead image: Douglas Kent