Clunch and Clay Bat
Although pieces of chalk were found in the some of the test pits that were dug in the village in 2013 none was specifically identified as the local chalk building material called clunch. It is made hard by extremes of climate and is sandwiched between the softer layers of chalk in Cambridgeshire.
Clunch was used extensively in medieval times as a building material in Cambridgeshire, although not as a primary material for houses which were typically wattle and daub. However, it would be used for footings, chimneys, boundary walls and small farm buildings.
It weathered poorly and was subject to frost damage but was used mainly because there was little local stone available cheaply. Lime wash was used to protect the surface. The blocks were carefully cut and mortared (ashlar) then used to form a wall.
Two of the listed dwelling descriptions mention clunch:
- Chiswick House in which, on the first floor, there was an early C17 hearth of dressed clunch blocks with ovolo moulding and jewelled stops at the time of listing.
- 9/11 North End: Willow Way Cottages has an early 19th century extension to the end which was probably clunch.
- It is also present in Holy Trinity Church.
There is some evidence that the locations of village settlements were linked to outcroppings of clunch as its position on top of other chalk provided springs of fresh water and this building material.
There were clunch pits on the Whaddon road near Meldreth but these were linked to the cement works in modern times. There was also a clunch pit near Mettle Hill and others in Orwell and Melbourn (the Whiting Company in Back Lane produced clunch called Melbourn Rock).
There are a number of clunch walled houses in Melbourn e.g. in Little Lane and Meeting House Lane and the photograph (below right) shows an exposed clunch wall in Melbourn in 1938.
There is an article on Melbourn Rock and the Whiting Company by Peter Simmonett in the Melbourn Magazine issue 76 Winter 2013 on page 63.
The Cemex site in Barrington still provided clunch for restoration projects in 2015. However it is now closed and housing is planned for part of the site. The main site for clunch production in Cambridgeshire was at Burwell which closed in 1962.
A similar material is Totternhoe stone from Bedfordshire.
There is documentary evidence of the use of clay bat in Meldreth: the former Dumb Flea Public House, 23 Chiswick End has an early nineteenth century addition of clay bat on a brick plinth. The former Green Man Public House at 33 North End had a nineteenth century clay bat stable. Clay bat at Meldreth House (43 High Street) was described as “clay batts on brick footings” probably around 1848. The old Congregational schoolroom was built of clay bats with a round stove and a chimney going up in the middle of the room.
Sarah Butler mentions cottages built with clay bat in her memoirs: “many of the picturesque old cottages in the village at the early part of the century were built with the local clay, which was made into “Batts” as they were called. Cottages built of this were warm in winter and cold in summer. Another disadvantage of clay bat cottages was that if the walls got really soaked with rain, the whole side of the house would fall out. There were many examples of this over the years”.
However there were no findings identified as clay bat in the archaeological test pits in 2013.
The clay would have been dug from pits in the neighbourhood as there are pockets of boulder clay underlying the chalk.
Clay bats were made from broken up clay, mixed with water, dung, straw, horse hair to seal it. Often horses would then walk across the material to mix it up. Wooden moulds would be used which were quite large (about 18 inches long by 10 wide and 6 deep). The bats were unfired. The Cambridgeshire Tile and Brick Company still make clay bats for restoration projects.
This material was mainly used in the eighteenth and nineteenth centuries. However it was prone to frost damage in a similar way to clunch and there are accounts in neighbouring villages of house fronts collapsing into the road during severe weather.
Little Shelford has a clay pit which was used to produce clay bats for houses in the village.
At the bottom of the economic scale people would dig out clay and chalk marl and add locally available binding ingredients to make a very unstable building material.
It is similar to cob and there was recently a project at the North West Cambridge building site on Madingley Road where cob structures were made.
- Building with cob: a step by step guide; Adam Weismann, Katy Bryce, Green Books (2006)
- Clay and Cob Buildings; John McCann Shire Library 2004
Flint is readily available locally and would have been used to face out walls as is the case with Melbourn church.