A higher purpose

The medieval church of St James in the grounds of the Abbey of Bury St Edmunds was nominated in 1914 as the cathedral for Suffolk. In 1959 work began to enlarge the church for use as a cathedral under the direction of Stephen Dykes Bower, cathedral architect from 1943 until 1988. Between 1963 and 1970 the East End was completely rebuilt, but funds ran out and only the concrete base for a future tower could be constructed. Other works were left incomplete.

At his death in 1994, Dykes Bower left a substantial bequest to trustees to finish the work. His generous legacy was not sufficient to raise the tower but was enough to secure Millennium Commission co-funding. This, together with a public appeal which raised more than £2.5m, provided the funds needed to carry out the project.

Outstanding leadership

Leading the construction was Horry Parsons, whose quiet personality fostered enthusiastic commitment from the team for the full five years. It was refreshing for a visitor like me to hear men express a sincere pride in their work and to see the quality of craftsmanship that resulted from this pride.

Tenders were invited in accordance with EU rules, but the successful bid was not based on price alone. The chosen contractor had to demonstrate the special qualities of management.

At an interview, shortlisted contractors had to describe how they would manage a team of skilled craftsmen. Bluestone selected Parsons as its project leader designate and he attended the interview. Although its tender was not the lowest, Bluestone won. Parsons likes to think it was his Suffolk accent that won over the client, but he had more to offer than that, having been with his company nearly 50 years, and with many prestigious projects under his belt.

The contract required a two-stage tender, with stage one covering the preliminaries, which included the management team, site set-up and insurance, and scaffolding, which was a major work package. A huge and complex buttressed scaffolding system was required to construct the 150ft stone tower. It had to be used for heavy lifting as well as for working on. Ninety-eight miles of tubes and beams were used.

Stage two covered the brickwork and the stonework. The extent and complexity of the stone cladding demanded a specialist contractor, but the tower is essentially a load-bearing brick structure, so the brickwork was just as vital.

Here Parsons demonstrated what it meant to him to be a builder. Rather than inviting a brickwork contractor to bid, he recommended to his directors that they bid for the work themselves, arguing that they’d be able to work as a traditional builder rather than just provide management expertise. It meant he could appoint and develop the team of craftsmen, and so control the standard of workmanship. It would enable him truly to lead the project. They agreed and asked him to prepare the estimate. The bid was successful. Parsons’ assistant was site manager David Palmer. They worked together closely to ensure the project’s success.

The North Transept

Work started in 1999. At ground level three vaulted cloister bays, with one extra bay, were built to link with the north cloisters built in 1959-61. Internally the mass concrete vaulting, finished with lime plaster, supports a higher level gallery. This was fitted with tiered seating to overlook the nave altar. A staircase from the north crossing leads to this gallery.

Externally the walling is built of Doulting and Clipsham stone. The two flank walls of the transept are of random flint rubble, on a brick core, while the north wall is patterned with flushwork of knapped flints.

The Lantern Tower

The gothic stone tower at the heart of the project is, in fact, a load-bearing brick tower faced with stonework that is bonded to the brick core. St James’s church was originally built of Barnack Stone from Lincolnshire. Owing to its popularity in the Middle Ages and later, most seams have long been exhausted. Fortunately it has been possible to open a new seam of Barnack stone to construct the outer walls, and the inner walls are lined with Ketton stone. After trials, a traditional lime mortar was used.

The existing reinforced concrete over the crossing, the base of the new tower, was found to have such significant irregularities that engineers had to carry out detailed measurements. These measurements determined a varying thickness for virtually every stone of the cladding in order to maintain the required half-inch gap around the concrete capping.

The Brickwork

The new elements were designed in the gothic style to harmonise with the original medieval church. Wherever possible the construction had to replicate medieval methods, even to the point of using imperial measurements over metric. This is why they bonded the exterior stone to the brick core so the whole acts as one mass of load-bearing masonry. The strength required by the structure has been achieved without reinforcement or metal ties, as these materials do not have a track record of lasting a thousand years.

David Peacock was the leader. Every brick of the tower, from the massive foundations up to the parapets, had to be laid with a full bed and with precise accuracy. The team had to develop special techniques in the use of modified trowels. The architect required a completely flat bed which was obtained by cutting the trowels, to remove the point, and creating a 75mm flat tip.

The brickwork was built to an imperial gauge using bricks made specially by Baggeridge of Birmingham. All fair face work has been built in English Bond while the core construction used quarter and half bonds. English Bond was introduced from about 1560 and the nave of the present building was begun in that century.

The four walls of the tower’s corners are exceptionally thick, up to six feet in places, and this forms some 70% of the work. Fellow craftsmen will appreciate the demands this made on bricklayers who had to work on top of the core. Much of their work was at toe level – nose bleed work, as it’s commonly known. To lay the full bed over such wide walls, required a technique not unlike icing a cake. The jointing of all exposed work was wood and ragged finished to give a full flushed effect to all the joints.

The bricklayers had to demonstrate the required craft skill and an attitude that would consistently produce high-quality work, but even then they underwent a skills development programme to prepare them further. Every brick to be laid, for every course, was drawn in detail by the architect. Many trials were carried out to familiarise them with the workability of the mortar.

The Lime Mortar

The company was issued with a series of mortar specifications for the various activities. Lime mortar was used for bedding and grouting stonework, bedding and pointing flints, laying bricks in general conditions and in damp-proof courses.

Recognised as an authority on preparing and using lime mortars, Michael Wingate produced the specifications. He worked with a team consisting of architect Gothic Design Practice, the BRE, structural engineer Brian Morton and Bluestone. He spent six months experimenting with numerous mix ratios, methods of mixing, timing of individual stages, various aggregates and water content. Despite this initial work, every mix needed to be finely tuned to be of practical use. Depending on the particular use, a range of materials was required: Blue Lias Hydraulic Lime from Dorset, Bleaklow Slated Lime Putty from Derbyshire, crushed chalk from Norfolk and a mix of soft sands from Suffolk Pits.

The process of mixing was, of course, critical to the final result. Two pre-mixes were prepared in a barrel mixer. These are a mix of hydraulic lime and sharp sand, which has a shelf life of six days, and a soft sand with slated lime making a putty which has a shelf life of months, probably years. A proportion of each pre-mix was brought together with chalk granules and water “to taste” in a pan mixer. The proportions and timing of each ingredient were accurately controlled in the mixing to maintain the required standard.

The stonework

Stone is the ultimate building material available to man. It imparts a sense of permanence and allows the designer, with the craftsmen, to produce a building that will mellow through the years to delight generations to come.

At St Edmundsbury Cathedral, the links with earlier cathedrals and their builders are remarkable. Barnack stone was used to build both the Abbey and the adjacent Norman tower. For many years the quarry was considered exhausted. But fate took a hand and a seam of Barnack was located which proved to be enough for cladding the tower. It was occasionally supplemented by a similar stone, Clipsham, to ensure that sufficient Barnack was available for areas facing severe weather exposure.

When quarried the stone was transported a short distance to the contractor selected to carry out all masonry work, Ketton Architectural Stone and Masonry. Here the stone was cut and worked. Each individual stone had to be set out using detailed drawings and these were produced by Peter Banister working in a small office in the garden of his own house. Each of the full size templates were drawn, and cut, to an accuracy of 1/32” with no tolerances permitted. Many hundreds of face and bed templates were required.

The arches presented a particular problem, as they had to be drawn full size to set out the curve of support centring and to prepare the templates. The floor of the village hall was the only surface large enough.

Brick and stone were bonded throughout the structure so that the whole acts as one mass of masonry in the way it would have done in a medieval building. Most 20th-century buildings other than housing use a steel or concrete frame to provide stability and load distribution. However, St Edmundsbury’s tower achieves strength and stability without reinforced concrete, metal ties or Portland Cement. The masons and bricklayers worked as a team. The stone facing was laid ahead of the brickwork by one course, thus enabling bonding across the stonework at intervals.

Each of the worked stones arrived on site in accordance with its scheduled position number. The completed tower was created from 3800 tonnes of worked stone, but such was the accuracy of the templates and the skill of the masons that only some five or six stones had to be replaced. The journey of each stone to its position in the tower was a fascinating path to follow. The required batch of prepared stones was carefully placed on a pallet, transported to a lift housed in the huge buttressed scaffolding tower and then raised to the working level. The pallet was then wheeled 50ft on an access bridge to the north face of the tower.

It then became necessary to distribute the stones around the external face of the tower and provide a means of lifting them for bedding on the section under construction. This was achieved in a most efficient manner. As each lift of the scaffold was raised, a suspended perimeter rail was provided that ran, continuously, around the centre line of the tower walling and above the masons’ heads. The rail carried an electric hoist, mounted on a powered bogey, which enabled the masons to hoist the stones, transport them over the top of the perimeter walls and by means of a hand held controller lower them gently onto their prepared bed. It was remarkable to see a half-tonne carved stone suspended only by the friction grip of a Lewis Pin precisely lowered on to its bed.

To bed the huge arch stones the masons employed their own special techniques. As each stone was gently lowered into position, small wooden wedges were placed under each corner and these carried its weight. The arch was completed in this way and the wedges withdrawn on the same day. This allowed the whole arch to bed firmly down on its joint lines and freed the centring for ease of removal.

Each craftsman had to interpret the intentions of the designer consistently and faithfully. Parsons successfully combined his roles as leader of the craftsmen and manager of the commercial demands of his company. His philosophy was simple: instruct clearly; constantly encourage; continually communicate; show appreciation; and keep smiling. It worked, as very few of the team left before their part of the work was completed.

High up on the north face, incorporated in the flint flush work of the tower parapet are the initials EE (for St Edmund). In recognition of his outstanding leadership the architect presented Parsons with a framed, detailed drawing of the completed project. He had changed the initials to HP.