The Georgians, Edwardians and Victorians knew all about bay windows and used them to try to make the most of the spasmodic sunlight that has always characterised the British climate. However, the Elizabethans also used the technique of glazing windows on three sides, and, pushing a point, one could argue that they derived the idea from the defensive towers that protruded from castle curtain walls throughout the mediaeval period.
In Elizabethan days the concept became quite refined and fortunately we still have many survivors not only full-face square ones but semi-circular, half hexagons, half octagons and one or two other variations.
But why is this tried and proven – and very British – technique used so sparingly by self-builders today? One reason, according to architect and Arts & Crafts expert Peter King, is the popularity of conservatories. If it comes to a choice Peter knows which he prefers. “A big bay window creates as much light as a conservatory but it doesn’t isolate the existing house from the garden – and it brings light into the house rather than keeping it away, as most conservatories do,” he says.
Peter likes to build at least one bay into every house he designs if the opportunity arises. So does award-winning architect – and Arts & Crafts specialist – Richard Holden, who created a full-height square bay window when he remodelled the south-west elevation of his 1959 brick-built house in Wimbledon.
Peter King did something rather more unusual with the end elevation of the new galleried extension to his Cotswold stone cottage. He inserted a two storey bay window with a central wooden mullion with six vertical panes of glass in the opening window on either side. Together with rooflights at the rear this ensures that light pours into both floors of the small extension. Another previous project involved adding a galleried bay that served two floors to a house dating from 1908.
Richard Holden also likes to create variations on the theme. In a refurbishment and extension to an Edwardian house he used an oak framed two storey bay containing large picture windows on three sides.
Architect and design expert George Baxter is also a great enthusiast for bay windows. “I’d like to see a renaissance of the bay in domestic building,” he says. “It is an area of self-build where there are far too many missed opportunities. Constructing bays need not necessarily be that expensive. They are an excellent way of breaking up an elevation and pulling light into a house.”
A useful trick when self-building on a site that is rather tight at the sides of the plot is to create a hanging or bracketed bay that is unsupported from the ground. This is a cunning way of stepping out a building close to the boundary where it might have otherwise been difficult or impossible to gain planning consent. Another technique is to pull the gable end of the roof forward to form the roof of the bay window. In Edwardian and Arts & Crafts style houses this can look very effective, especially when the triangular space above the bay and beneath the gable end is tile-hung. When this technique is used George advises extending the roof overhang and bringing the bargeboard away from the wall to allow for the shadow effect and to make the bargeboard appear functional and avoid it looking as though it has been stuck on.
“There are many ways to save on costs with bay windows,” George says. “One is to make the main roof catslide down over the bay. This way a new roof with framing and valley gutters will not be needed. This is also a good way to add interest to your house.”
George’s other key piece of advice is to self-builders who want a door in their downstairs bay. “In many ways the ideal bay has no doors, as the best use of space in my view is to have a window seat above a cupboard or other form of storage space, and a window sill on which you can put things on either side. If you decide on a door, however, there are two options: one is to go for a full-height glazed panel on either side; the other is to have a sill on either side.
“The key is to design your bay from the outset and to have a proper drawing and see the bay is correctly set out. If you just design the bay as you go along you will probably lose space, especially if you have cavity walls.”