Mud on the wall

Protecting a parish asset

For some residents, the mud wall fronting 70 High Street in Kibworth Beauchamp in Leicestershire is probably seen as something of an eyesore which they might notice or choose to ignore when leaving the Co-op car park. Yet despite its shabby and unkempt appearance, it is a structure valued by many, as evidenced by comments often received by Kibworth Beauchamp Parish Council.

Its location, almost at the end of the High Street and close to an important and ancient route increases its significance as part of the local heritage.  Nearby, 66 High Street, a building of impressive proportions, was almost certainly a farmstead associated with land stretching both to the north and south of the road.  Although a later building, its presence suggests that 70 High Street was a farmworker's cottage, possibly developed out of earlier farm-related outbuildings such as stables, part of a farming enterprise that managed this land on the edge of the village.  The 1886 Ordnance Survey map shows the cottage as the last residential property on the High Street.

The cottage on the 1886 OS Map (circled in red)
The cottage on the 1886 OS Map (circled in red)

The wall is a listed building, described in the Natural Heritage List for England as the former front wall of an eighteenth-century cottage, long since demolished.  It is made of mud with a rubble stone supporting plinth. A modern corrugated iron coping was been added at some stage in its history, presumably to serve as protection against the elements.

Its condition has been a matter of concern for some time, and there have been various attempts in past years to refurbish it.  There was correspondence in 2007 between Kibworth Beauchamp Parish Council and Harborough District Council about its deterioration.  In 2015, much of the rendering began to fall off, prompting calls for the Parish Council to act.

The wall before refurbishment
The wall before refurbishment

In January 2016, Kibworth Beauchamp Parish Council's Village Focus Group sought the advice of a local professional who had previous knowledge of the wall.  The late Anthony Goode from nearby Slawston and a recognised authority on the maintenance of early buildings, attended a site visit with the Parish Clerk. His knowledge of the structure was revealing. The rendering which had decayed was modern.  Further research confirmed that rainwater had seeped between the rendering and the original wall. The wall itself showed no deterioration whatsoever. The problem had been caused by the modern rendering which, because of its constitution and composition, had not adhered to the original wall.  Markers which had been placed at the back of the wall to measure any movement indicated that the wall was sound.  Checked in October 2016, in nearly two decades, the wall had not moved.

An early photograph of the cottage (right)
An early photograph of the cottage (right)

Although a listed building, the Parish Council had no powers to act without the approval and co-operation of the owners.  Fortunately, the Waterloo Housing Group, in association with the Harborough-based Seven Locks Housing, responded positively and agreed to work with Anthony Goode to ensure structure's future wellbeing.

Anthony explained that he normally divided his approach to this type of work into three categories, equal in importance, these being preparation, application and protection.   As well as the inevitable paperwork, the preparation involved removing only the damaged and loose plasterwork as needed, and slightly undercutting back around the edges of what remained to create a key for the new work.   Using a bristle brush all the newly exposed mud wall was brushed and cleaned down to remove loose debris and dust before spraying and dampening down with water.

The lime plaster was mixed several weeks before it was needed, and rested to allow it to mature.  Goat hair reinforcement was added just before use to prevent the lime rotting it away. The mix was a measure of one part sharp sand to 2.5 parts of lime putty.  Plaster can be applied by plastering trowels, but in this case, Anthony and his team literally threw it on to the wall with a purpose-made roughcasting or harling trowel.  This is a well-known technique which is commonly found in Scotland on masonry buildings of solid wall construction.  The Encyclopaedia of Cottage, Farm and Villa Architecture (1833) defined the process as 'outside plastering [which is] adopted on the outside wall of a cottage to keep them dry; a second purpose is, to render them ornamental, either by imitating stone, or producing a surface more curious or agreeable to the eye, than the rude materials concealed behind it.'

A further technical reason for choosing this form of application was that, on a mud wall there is little key, so relying mainly on suction. In the harling process as the plaster mix hits the wall it expels the air out behind it to form a better bond between the two.  As the plaster firmed up it was rubbed up with floats to produce a coarse finish following the contours of the wall.

It was then protected by an absorbent material covering to prevent the lime putty plaster drying out too quickly. Unlike cement, putty lime does not set hard.  The lime needs warmth to carbonate, and depending on the time of year and the temperatures, this can take several weeks.

Residents expressed delight in the completed work following the removal of the protective covering in November 2016.   Decorative plastering can often mask a building's history whereas this project has succeeded in protecting a small part of Kibworth's building heritage and has allowed it to speak for itself.