Harmondsworth Barn © English Heritage / Photographer Boris Baggs

The Cathedral Of Middlesex

27th April 2012

Question: When is a barn not just a barn?

Answer: when it’s the biggest medieval one in the country to survive unaltered from its heyday.

Jack Watkins went to explore…

If you were planning an investigation of the hidden treasures of London’s Green Belt, the environs of Heathrow probably wouldn’t immediately shoot to the top of your list. To learn of the existence of a village like Harmondsworth, minutes away from the airport runways, therefore, comes as a pleasant surprise. It really is a village, complete with a small green, a church with a fine tower – Tudor in its uppermost parts – and a finely carved Norman doorway, and several dwellings dating at least as far back as the eighteenth century. The architecture historian Nikolaus Pevsner thought its setting was an all-too rare glimpse of the quiet Middlesex countryside. ‘Transport it to Kent or Worcestershire,’ says the Harmondsworth History Trail leaflet, ‘and it would be idyllic’.

Pretty as it is, the village’s real claim to distinction lies in the existence here of what Sir John Betjeman dubbed ‘the cathedral of Middlesex’. The Great Barn is one of the most complete and unaltered Pre-Reformation buildings in this country. Built in 1426, its mere survival is something of a miracle, given that it is essentially a timber structure and thus highly susceptible to fire. Even more remarkable is the endurance of the structure in its original form – 95% of its fabric is estimated to be intact – most unusual in a barn of such antiquity and which, as a working farm building throughout its history, would normally be subject to alterations over time.

In fact, despite its longevity, the barn had probably never been under greater danger than in the last decade, so when the Friends of the Great Barn conducted its first major opening to the general public this Easter, after it had been acquired by English Heritage, they could have been forgiven for letting out a collective sigh of relief. From keeping an anxious eye on its gradual deterioration under a neglectful previous owner, they can now turn their thoughts to planning how best to present its remarkable history to visitors.

Justine Bayley, secretary of the Friends, admits that she’s something of a newcomer to the community, having only moved into the village in 1995, but she says there are others who can recall when the barn was still part of a working farm. “The last harvest was brought into the barn in 1978,” she explains, “but what finished it as a building used for the storage of produce was when the farmer, who’d been here since the early 1950s, had a fatal accident on his tractor. A construction company brought the farm and demolished many of the more ramshackle old farm buildings, while most of the farmland was sold off. It is still managed as farmland, but is now split between different holdings”

Fortunately, the company continued to keep the barn in reasonable repair and to allow the villagers occasional access for activities such as crafts fairs. An office complex built adjacent is sensitive in its layout and fabric to the historic context. However, Justine says “alarm bells started to ring” when the company went into receivership. Assets were sold off, and the barn was then offered to Hillingdon Borough Council for £1. They were deterred by likely costs for repairs and upkeep, however, and instead it was bought by a property speculator in 2006.

“It was around the time the third runway at Heathrow was under consideration (the barn’s north wall is only five metres from the boundary of the area earmarked for the airport expansion) and I suspect he’d hoped the land would be compulsorily purchased and that he would make a mint on it,” says Justine. “He completely neglected to look after the barn, and tiles were falling off the roof and the weather was getting in. When English Heritage sent him an Urgent Works Notice for emergency repairs to make it wind- and water-tight, he refused to comply.”

With a High Court case pending, an agreement was finally reached by which English Heritage purchased the barn for £20,000. Simon Thurley, the organisation’s chief executive, called it “one of the greatest medieval buildings in Britain,” and vowed to “complete the repair of this masterpiece.”

The Friends now have a three-year lease to manage the day-to-day care of the structure and its opening to the public, while English Heritage carries out a structural survey. From the outside, apart from its incredible (192ft) length, the barn is no great looker, but entering with Justine, I almost expect to see an altar at the far end, so effectively is its layout – a central nave, with the side aisles divided into bays – modelled on that of a church. Irresistibly, my eyes are continually drawn up to the timber rafters 40ft above, just as I would be in a cathedral, confirming that Betjeman, as so often, found the right phrase to describe its effects.

Justine, an archaeological scientist specialising in ancient technology, points out clues to the ancient construction, such as irregular wood saw marks – contrasting with regular patterns of machine-sawn wood used when a fire damaged the first bay in 1972 – and the carpenters’ marks made to ensure correctly ordered assemblage. She explains that dendrochronology of the tree rings has dated the massive arcade post timbers to around 1426. “Of course, that only tells you when the timber was felled, not when it was used for construction, but it would have been fairly immediately afterwards because green timber was more easily worked for something of this scale.” In fact, in a pleasing example of documentary evidence and science working together, contemporary records have been found of instructions for the barn’s master carpenter William Kyppynge to go out into the forest of Kingston-Upon-Thames in 1425, to find oak trees for ‘the new barn’ at Harmondsworth.

You might be wondering who would have needed to build a barn on such a scale. In 1391, the manor of Harmondsworth had been bought by William of Wykeham, bishop of Winchester and founder of colleges at Winchester and Oxford. “He was concerned his successors wouldn’t have the same enthusiasm for his educational endowments, and the farm was to support the finances,” says Justine. “A large manor producing a lot of corn needed a big building to store it in. The barn was really quite hi-tech for its age.”

If the chief reason for its Grade I listing is its architecture, there is also a fascinating story of Harmondsworth’s – and Heathrow’s – lost farming history, which Justine is keen that the barn should illustrate. She shows me a photograph of a heavy horse ploughing match of 1935 at Heathrow village, on the site of the current Terminal One. Other pictures show women from the turn of the 20th century in the fields packing onion baskets, and traditional orchards.

“The soils are a good loam in this area and there was a long tradition of cereal growing and market gardening. This is something people are no longer aware of,” she observes.

Put next to the ancient barn, the photos are remarkably recent, even if the world that its inhabitants moved in has been swept away. In fact, as well as being a gem of medieval vernacular architecture, the Great Barn also offers a connection to a past that has gone within a lifetime. That’s another reason for ‘raising the rafters’ at its recent rescue…

Harmondsworth Great Barn is open on the 2nd and 4th Sundays of each month, 10-5pm, until the end of October.

Admission free. No access at other times.

See www.english-heritage.org.uk/daysout/properties/harmondsworth-barn

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