PROPERTY: TOP OF THE GLASS PERIOD FEATURES 1: STAINED GLASS

The dream house, for many people, should display what agents call "a wealth of original features". It doesn't seem a lot to ask. Around 25 per cent of Britain's 20 million dwell-ings were built before 1918, half of them modest Victorian or Edwardian family houses. Every urban borough has hundreds, yet it's virtually impossible to find an elderly property that still has its own teeth: the sash windows and ceiling roses, tiled fireplaces and panelled doors so dear to our hearts now. Searching for of one of these well-preserved gems is a dispiriting experience. Over the years, their inhabitants have remodelled such houses to suit themselves. But the flush doors that were de rigeur in the Fifties or the prized aluminium conservatories of the Eighties are to our tastes insensitive meddling. So coming across a 19th-century house untouched by the 20th is an unlikely scenario. But the alternative, pouring thousands into the restoration of stained glass, panelled doors, sash windows and plaster mouldings, is an unnerving prospect. Is it worth the hassle and expense? Investing in the conservation of antique decoration isn't merely nostalgia; it also makes good economic sense. Phillip Davies, a regional planner for London with English Heritage, suggests that period authenticity can add between 5 and 15 cent to the value of a house. "It's very difficult to strike a balance between sensible conservation and the needs of homemakers to assert their individuality," Davies says. "However, the boom in architectural salvage and crafts industries shows that people are reversing the destructive trends of the last few decades." Conservation and restoration, suggests Kit Wedd of the Victorian Society, is not the sole preserve of the rich or the heritage professional. "Anyone who owns a period home can make an active and positive contribution," she says.

"WINDOWS are the eyes of a building," says the architectural historian Dr Steven Parissien between shots in an English Heritage video production. While extolling the traditional timber-framed casement and the double- hung sash, he points out that these and other forms of period fenestration are under threat. Vulner-able to neglect, decay and "the dreaded double- glazing salesman", architecture's eyes are being systematically punched out.

Nothing irks the conservationist, or the discerning house buyer, more than unsympathetic replacement windows framed in anodised aluminium or unplasticised poly vinyl chloride (or uPVC). The English Heritage film, Framing Opinions, is part of a nationwide mission to encourage home owners to repair and restore rather than replace their weathered or wonky windows.

In many of Britain's thousands of conservation areas, ruinous modernisation is controlled by planning statutes, but millions of worthy windows are left undefended and in many cases the damage has already been done. This is not just a matter of aesthetics. The campaign entreats us to cast a fresh eye over our period glazing. Because by replacing windows, the chances are, you are not only throwing out a set of finely moulded astragals and a nice bit of old joinery, but also several squares of original, hand- made glass.

The acid test is in examining the reflections cast on interior walls when light filters through old glass. Where there are swirls and ripples there are "reams" and "seeds" (glaziers' terms for waves and air bubbles) - sure signs of age as these imperfections were ironed out at the beginning of the 20th century and eradicated when flat, flawless "float" glass was introduced in the 1950s.

Glass is one the defining characteristics of a historic window and connoisseurs maintain that the new material lacks the life and sparkle of the old. Throughout the 19th century, light filtered through hand-blown, spun, rolled, etched, coloured, stained, sand-blasted, pebbled and textured glass - but it's only recently that it has been put on the agenda of legacies worth preserving.

In Eileen and Robert Skinner's restored Victorian house in the Pollokshields conservation area of Glasgow, light filters through a mosaic of hand-made coloured glass held in place by a web of lead cames (strips). One rear window, set into an exterior door, features a Rosetti-style maiden in a white robe riding on a swan across a glazed landscape washed with watery blues. When the sun shines, the image casts a rainbow of patterned light on the room's polished wooden floor. And this magnificent original feature represents the revival of a medieval art in which colour was achieved by adding metal oxides to molten glass (known as pot-coloured glass) or by fusing stains, paints and enamels to plain surfaces during firing. (The term "stained glass" is a technical misnomer as only the yellowy- orange tones are the result of staining.)

The work is unattributed but Eileen's research has unearthed an original catologue from a 1895 Arts & Crafts exhibition that features an identical work by E A Davidson, called Leda and the Swan (in Greek mythology, Leda was wooed by Jupiter in the guise of a swan). The design was executed by the now vanished Glaswegian glassmakers, James Cooper & Sons. And as the Skinners' home was once owned by a shipbuilding family named Cooper, Eileen believes that the former exhibition piece ended up in her billiard room, an extension to the 1890s house added in 1913.

Other decorative glassworks in the house include a multi-coloured screen set into the front door, an internal panel depicting a little sailing ship and a concave stair light which, Eileen says, is cleverly angled to maximise light through a north-facing aspect. She believes that these pieces might have been made in the studios of Stephen Adam or George Walton, two of the many famous architectural artists whose work lights up Glasgow's dark tenements and stone terraces with brightly, coloured panels of stained glass.

Glasgow has some of the finest domestic stained glass in Europe. At its best, it is seen from indoors, but if you walk the Victorian streets of the city's West End, you can still see the leaded outlines of flowers, birds, rustic scenes, seascapes, heraldic crests and a polychrome of abstract and figurative designs, including pre-Raphaelite nymphs and more mythological maids. David Gauld, Oscar Paterson and Charles Rennie Mackintosh are the best known of dozens of glass painters who contributed to the chiaroscuro of the city's interior landscape.

As mentors of the distinctive Glasgow Style, which emerged in the 1870s, Scottish designers continued to influence British household stained glass right up until the building boom of the 1930s. Versions of Oscar Paterson's naively graphic images of galleons at sea and little Dutch girls disappearing into rural sunsets, for example, were to become a decorative cliche of the inter-war suburban semi. But the 19th-century fashion for stained glass was initially seeded in the scholarly work of an English barrister called Charles Winston.

In 1847, Winston published a fat, illustrated study on England's surviving medieval painted glass. At the time, the architects of the Victorian Gothic Revival - preoccupied with all things medieval - were already experimenting with coloured glass, but Winston's book precipitated the rediscovery of lost technologies and fuelled a British renaissance in crafts-led glassmaking industries.

In the mid-1800s, the 17th-century taxes on glass and windows were abolished, making glass considerably cheaper. In 1851, the Great Exhibition at Joseph Paxton's Crystal Palace inspired public enthusiasm for decorative glazing and by the 1860s the Arts & Crafts movement, led by William Morris, started to lift stained glass out of an exclusively religious setting and into secular public buildings, stately homes, and finally private houses. By the end of the 19th century, stained glass - used particularly in front doors and fan lights - was an ubiquitous feature of the upwardly-mobile, middle-class family home.

"The Victorian house was seen as both a refuge and a symbol of new affluence," says Caroline Swash, a London-based stained-glass artist and historian. "The use of coloured glass combined illumination, conspicuous ostentation and privacy." It served particularly to screen the moneyed middle classes from the prying eyes of backyard hoi polloi, to hide the view of a neighbour's brickwork, or as a cheerful counter to a dreary urban landscape blackened by soot and industrial grime.

Caroline has identified Dulwich and Hampstead as two London residential areas still rich in original coloured glass, but much of what survived the Blitz has been destroyed by home improvement. It was Glasgow's post- war decline that saved much the city from decades of redevelopment and damaging DIY.

When the Skinners bought their detached house in Glasgow in 1994, it had not been modernised since it was built a century earlier. As a testament to the demand for unsullied period properties, the Skinners were among 100 potential buyers who viewed the property and 30 who tendered an offer. All the original oak panelling, light fittings and marble fireplaces were intact, but some of the glass, Eileen Skinner says, was "in a terrible mess". The previous owners had boarded up the billiard-room window as a crude security measure, and they had driven nails right through Leda and the Swan. Some of the the glass was cracked and broken and soldered joints in the leaded framework had split.

Susan Bradbury of the Stained Glass Partnership in Kilmarnock restored the window, using techniques that haven't changed since the Reformation. "If a group of medieval craftsmen walked into our studios, they would feel perfectly at home," she says. The only modern innovations are glass- cutting tools and silicone adhesives - which reduce the way light catches a bonded crack. The range of coloured and tinted glasses now available is also unprecedented, though most of the material comes from France, Germany and Poland. The only 19th-century factory in Britain, still producing hand-blown, pot-coloured glass is Hartley Wood in Sunderland, a firm founded in 1892 and now run as a co-operative.

One of the myths about stained glass conservation, Susan says, is that old glass cannot be matched with a modern equivalent of the same colour. It is true, however, that the glass is expensive and the restoration work is very laborious. People are put off by costs, but the Stained Glass Partnership has, none the less, seen a recent increase in domestic restoration commissions. The only damage that cannot be remedied is caused by cleaning glass with abrasive chemicals (which scratches surface designs) but even a missing window or door panel can be remade.

To most glass artists, restoration is bread-and-butter work; the meaty jobs are in originating new designs. For the client, Caroline Swash says, commissioning glass artworks for the home is an opportunity to add a contemporary dimension to a period property. "It's important is to take the rhythm of the architecture into account, but otherwise the choice of design is a matter of personal taste. Some go for the historically correct, others prefer modern abstract designs and geometric shapes." Common commissions include coloured panels for front doors, room dividers, conservatories and bathroom windows.

In the case of the Skinners' Leda and the Swan, the original glass mosaic was carefully taken apart and reset in a new lead framework. Broken pieces of the jigsaw were either replaced with new or reclaimed glass or carefully bonded together. The whole process cost the Skinners around pounds 1,000. They think that it's money well spent. "It's a work of art," Eileen says. "I can't believe that anyone would ever dream of removing or destroying such a beautiful thing."

But this is one period feature where personal taste plays a major part in its survival. "Some people love the way coloured glass images animate an interior," says Sally Rush, a glass historian. "But modernists hate it. Others associate it with a rather vulgar period of design, and there's a common myth that all stained glass looks churchy and casts a dim, religious light."

To Doreen Logan, an art teacher, it's no myth. When she bought her Edwardian house in Glasgow 11 years ago, she removed some of the stained glass lights from a sash window in her dining room, precisely because the design - a delicate Art Nouveau tree of life - darkened the interior. "It was absolutely horrible to have so little light and no view in such a big room," she says.

She came to a reasonable compromise by removing two sections of plain, green pebbled glass from her six-panelled sash window and replacing them with clear "restor-ation" glass. Now she has a beautiful pictorial window and a view of the garden. The green panels, meanwhile, have been incorporated into an interior door. Further examples of stained-glass artistry line the upper sashes of one of the bedroom windows, but Doreen is waiting for "a lottery-win situation" before tackling restoration. The conversion of her dining-room window, however, cost a relatively modest pounds 350.

In cities such as Glasgow, which saw their major expansion in the late Victorian era, coloured panels are a common feature of Victorian sash windows, and because of their outstanding pictorial qualities, they are readily perceived as works of art. But according to a window conservation expert, Giles Hamilton, the same could be said of any example of period glazing.

"A window is like a piece of furniture," he says. "And if you were to commission a cabinet-maker to reproduce a Georgian or Victorian sash window, you would have to ask for a piece of furniture that could be left out of doors in all weathers and temperatures and survive anything up to 200 years of neglect."

He points out that making a sash window in, say 1850, involved around 10 different trades. The whole ensemble was an efficient system of joints, pegs, cords, pulleys, counter-balancing weights, shutters and brass catches. The timber was deal or Scots pine, cut from mature trees, highly resistant to rot and far superior to anything available now. And what is left of hand-made glass is a finite resource - a few modern craftsmen are making reamed and seeded glass, but you can't reproduce age.

Giles's company, the quirkily named Sashy and Sashy ("if you use the word windows in a trade name everyone assumes you are selling double glazing"), contributed to the English Heritage video Framing Opinions, by demonstrating the conservation-friendly art of taking rattles and draughts out of time- worn windows. Where possible, original timber frames are renovated, broken panes are replaced with reclaimed antique glass, weak joints are reglued, pulleys oiled and old putty renewed. The worst cases of decaying frames can be replaced with exact replicas, with or without double glazing. One typical customer, whose windows let in draughts but refused to open, paid pounds 1,600 to have five 125-year-old sashes sympathetically restored. "It's still a cheap way to add value to a period house," Giles says.

Meanwhile, replacement-window companies (who charge about pounds 600 to double glaze a sash) continue to offer persuasive arguments. Plastic frames, they say, never need painting; and double glazing prevents heat loss. What they don't tell you is that uPVC yellows with prolonged exposure to sunlight; and it cannot be painted. And on the subject of insulation, Kit Wedd of the Victorian Society says that you can't beat a pair of good thick, lined curtains. Or folding wooden shutters, another period feature that has been consigned, all too often, to the skip. !

NEXT WEEK: Doors

WINDOWS ON THE PAST

HOW TO FIND STAINED GLASS

For a list of stained glass artists contact the British Society of Master Glass Painters on 0171 208 8208. The Skinners' window in Glasgow (see text) was restored by the Stained Glass Partnership (01563 538189) based in Kilmarnock. Doreen Logan (see text) used Rob MacInnes (0141 946 5330). In London, Patti House (0181 778 2836) undertakes restoration and contemporary design commissions. The 125-year-old London studios of Goddard & Gibbs (0171 739 6563) restore and originate decorative glass for churches, public buildings and private houses. The London Door Company (0181 947 7771) specialises in repro Victorian stained and etched glass-panelled doors.

HELP WITH RESTORING WINDOWS

For information on Sashy and Sashy's nationwide window rejuvenation services (see text) ring 01342 823408. Ventrolla (01423 870011) also specialises in renovating timber-framed period windows. The Original Box Sash Window Company, in Berkshire (01753 858196), produces double-glazed replicas of period sashes. The London Crown Glass Company (01494 871966), based in Buckinghamshire, makes hand-made "conservation glass" with built-in "antique" imperfections.

PLACES TO VISIT

Glass historian, Sally Rush (0141 632 1721) can arrange individual guided tours of Glasgow's stained glass on request. The Stained Glass Museum at Ely Cathedral ( 01353 667735) is open daily from Easter until October. The museum contains many examples of English ecclesiastic glass from the 14th to the 20th century, including work by Morris and his associates, Lowndes and Drury, Pugin and Burne-Jones.

The William Morris Gallery, Forest Road, London E17 4PP (0181 527 3782) is open Tuesday to Saturday and the first Sunday of each month. Dedicated to the work of Morris and his associates and their followers in the Arts & Crafts movement, the museum displays examples of domestic stained glass. Special exhibitions are planned for this year, the centenary of Morris's death.

Linley Sambourne House, 18 Stafford Terrace, London W8 is owned by the Royal Borough of Kensington and Chelsea, curated by the Victorian Society (0181 994 1019) and is open to the public from 1 March to 31 October. This, the home of Punch cartoonist Edward Linley Sambourne, features a number of striking stained glass panels. The sunburst and swallow motifs depicted in the drawing room window later reappeared in stylised forms in thousands of Thirties' semis.

The Charles Brooking Collection, at Greenwich University, Dartford, features a permanent display of historic window types. Telephone 0181 331 9897 for appointments. A smaller collection is kept at Charles's home in Guildford, Surrey (01483 504555).

FURTHER READING

Framing Opinions, a leaflet on window conservation, is available from English Heritage on 0171 973 3000. The Framing Opinions video is available, from E H postal sales on 01604 781163, price pounds 11.95. The Georgian Group (0171 387 1720) publish A Guide to the History and Replacement of Georgian Windows, price pounds 2.75. The Society for the Protection of Ancient Buildings (0171 377 1644) produce a pack on The Repair of Wood Windows, price pounds 4.00. Cathedral Communications (01747 871717) produce The Building Conservation Directory (pounds 14.95), a useful guide to specialist services/suppliers relating to a range of restoration disciplines including stained glass. Glasgow West Conservation Trust has produced a detailed, colour illustrated manual on Domestic Decorative Glass. For copies (price pounds 10) contact the trust on 0141 339 0092.