Monday, 30 August 2010

Sash windows installed

Sash windows have been installed in the basement of 6 Fitzroy Square to replace the full-width barred crittal window put in (in 1971) by a previous occupant, the NatWest Bank. The work involves reinstating not just the windows but the parts of the front facade between and above the sashes, all of which was removed to accommodate the crittal window. By way of an added complication, the crittal window sat within a massive steel-girder frame, which has been kept on the advice of structural engineers; fortunately, with some minor tweaking, the box sashes and shutter housings fit comfortably within it.

The bespoke sashes have been hand-crafted by traditional joiners, with the design based on surviving eight-over-eight sashes elsewhere in the terrace. By the 1790s, when the east side of Fitzroy Square was built, six-over-six sashes were used on the main floors, but slightly more old-fashioned eight-over-eight sashes were installed in basements, a service area where the expense of larger panes was unnecessary - and given that the basement windows were a matter of feet away from the coal vaults and a matter of inches away from the heavily-trafficked steps down to the basement, damage to panes was far more likely than in upper floors, so it made sense to put in smaller panes that were cheaper to replace. Conventional six-over-six sashes will be reinstated on the ground floor, where again the original sashes were replaced by the bank (this time in favour of single panes with frosted margin lights).

For the glazing bar profiles, we have copied a delicate moulding detail from a single surviving mahogany sash at the rear of 6 Fitzroy Square. The boxes within which the windows themselves are mounted are also hand-made, the product of many hours' labour by craftsmen, but they are almost completely hidden when installation is complete. This is a legacy of fire protection measures introduced in the 1774 Building Act, which stipulated that the box sash be covered by masonry, with only the frame of the window itself exposed. The depth of the reveal (the window is set back several inches from the face of the building) also has its origins in eighteenth century fire protection legislation.             

The reinstated walls are being rendered flush and then painted a colour specially developed by paint expert Patrick Baty to imitate Portland stone. The ground floor and basement have been painted since the mid nineteenth century as a way of masking dirt-ingrained stone, and it has been decided to continue that practice, largely because 150 years of absorption of paint oils and other residues would leave the stone permanently stained and uneven in appearance. The Portland stone on the upper three floors has always been, and remains, exposed, with a whole array of fossils clearly visible from the pavement, along with some patching-in following damage in the war, when four Adam houses in Fitzroy Square were destroyed by bombs. (Their facades were rebuilt in the 1950s).              

The reinstatement of the front facade to the Adam design, part of a wider basement improvement project, is being funded by our American Friends, whose support we gratefully acknowledge. Fittings for the new sashes and their shutters have been kindly donated by Charles Brooking, who runs the excellent Brooking Collection.    

Sunday, 15 August 2010

A curious case of iron-stained stone

The local sandstone at Belsay, in Northumberland, is shot through with iron ore deposits, with the result that the cut stone, used for building in the eighteenth and nineteenth centuries, is liberally flecked with black spots that become more prominent with weathering. The effect is distinctive and odd, as if buildings have been randomly sprayed with grapeshot. Good examples are in Belsay village, where the quality of the ashlar used for ordinary shops, as seen here, is a telltale sign of aristocratic patronage, and also at Belsay Hall itself, a staggeringly austere essay in Greek Revival architecture created in the 1810s when the Monck family decamped from the nearby castle, where they had lived since the 14th century and which still exists in a wonderfully unspoilt setting. Well worth a visit.