Bungaroosh

Close-up of a bungaroosh wall in the Round Hill area of Brighton

Bungaroosh (also spelt bungeroosh, bungarouche, is a composite building material used almost exclusively in the English south east including London and the seaside resort of Brighton and its attached neighbour Hove between the mid-18th and late 19th centuries, when it grew from a fishing village into a large town. Bungaroosh is almost always found in buildings of that era in the town and in its near neighbours Worthing, Eastbourne and Lewes, but is little known elsewhere. This wall building material was driven by cost, need and high brick taxes .

Bungaroush (often spelled bungaroosh)  is made principally of lime, gravel, coarse sands with nodular field (and some) beach flints with brick fragments or snaps as part  coursing, with other to hand rubble added. All were locally sourced.

Hot limes were also evident in the mix where full exposure was planned for, as some unslaked particulates within testify. Farmers were lifting nodular flints out of the downs as tilling, piling them on the side of the fields and glad to see them gone. Beach pebbles are the wave abraded versions and are often found in the mixes. Nodules were best, as being sharp edged they keyed well to each other. Bricks were fired unevenly in those days, being clamp fired, and many were half baked and easily snapped, so there were many of these. Some even less baked bricks were crushed to a powder and then added to the lime mortar. Being a form of pozzolana gravels, these were composed of grit sands and raddled stuff such as  small busted flint shards and brick rubble. When ready mixed as a semi-wet mix, floor sweepings, including straw, wood shavings and even a boot sole once seen embedded were  incorporated forming a very tough integrated whole. That is Bungaroosh. It is very similar to roman concrete. It is made of elements costing very little because they were easily available. Field flints are quite nodular because they were formed from sea sponge remains laid down along with shellfish (mainly siliceous planktonic microorganisms) over 95 million years ago.

The manufacture of bungaroosh involved placing miscellaneous materials, such as whole or broken bricks, cobblestones, flints (commonly found on the South Downs around Brighton), small pebbles, sand and pieces of wood into hydraulic lime and then shovelling it between shuttering until it has set( carbonated). The shuttering (formwork) process typically involved erecting a wooden frame, with shuttering planks, putting in the lime and adding solid materials to this mixture. Other structural fittings, such as brick piers or wooden lintels, could then be added if more support was needed or other structures were to be added. This was particularly common in Brighton,Hove and London where bungaroosh walls were often built behind the impressive stuccoed façades of Regency-style houses. The material is particularly prevalent in the early 19th-century squares, crescents and terraces of Brighton's seafront, such as Regency Square, Royal Crescent and the Kemp Town estate. Often it was then rendered with a lime-based mixture and painted with lime.. This produced a consistent, regular surface which could be used to build the symmetrical façades.

A tiny bit of history:  Lime rubble concrete has been around for thousands of years. The Romans used it to  form the massive domed roof of the Pantheon (with a lot of pumice lumps also) which is still the largest unsupported lime concrete structure in the world. (Whole book on the product here.) https://www.amazon.co.uk/Building-Eternity-Technology-Concrete Engineering/dp/1789256364 uses lime as in Roman concrete and cement. This exponentially hardens over time and to date there has never been a large failure of a bungaroosh wall. If holes are cut in it though or cement is used it stops this product from breathing, allowing damp permeation in and out and also cutting said holes can cause localised failure.

How bungaroosh was built. The foundation was always started as a scraped deck down to virgin chalk or clay. Usually started with bricks laid in a couple of diminishing courses (spread-foot) onto a semi-dry mix of hot or slaked lime sand and aggregate. Timber staves held planking that were braced into position each side then two or three inches of a heavily aggregated lime mortar was shovelled in, then flint, snapped brick and more lime was layered and coursed in on top. This process was repeated up to a height of about 18 inches.

When this section was sufficiently firmed up and compressed, the boards were moved up and the process was repeated.  As the wall was erected timbers could be inserted to both steady the pouring in of the mix and act as braces, providing fixing points for cavities battening for Lath and plaster. In many cases as sole plates for joists. Where windows and doors were to be located, the surrounds and returns were almost always quoin finished in brick as flint and lime cannot be used to create viable corners, it was a bit too coarse.

Chimneys and flues were also made with brick quoined jointing. Party/fire walls diminished in width as rising each floor with the stepping occurring within the joist voids. Sometimes these acted as resting locations for these  beams and joists. The attic walls were sometimes only 12” thick but the basement walls were found to be at least 24”. Houses of five floors being 30” or larger on occasion.   

As a bonus, these wall cores were most of the time filled in with loose flint material and some limed mortars  so as to retain a lot of small voids within its construct that have been evidenced at excellent at noise suppression.

The etymology of the word is unknown, so as it’s unknown speculation is simply speculation.

https://www.heritagebuildingadvisors.co.uk/projects/bungaroosh

See also

• Buildings and architecture of Brighton and Hove
• Core-and-veneer

References

Bibliography

• Antram, Nicholas; Morrice, Richard (2008). Brighton and Hove. Pevsner Architectural Guides. London: Yale University Press. ISBN 978-0-300-12661-7.
• Collis, Rose (2010). The New Encyclopaedia of Brighton. (based on the original by Tim Carder) (1st ed.). Brighton: Brighton & Hove Libraries. ISBN 978-0-9564664-0-2.

Other resources

• "Living with … bungaroush" (PDF). Archived from the original (PDF) on 7 January 2016. Retrieved 18 February 2013. (1.4 MB) (from The Regency Society) Author is Neil England
• "Flint and bungaroush". Building crafts & skills. The Regency Town House. Archived from the original on 25 December 2013. Retrieved 21 February 2013.
• Bungaroosh, an article written by Neil England Affiliate member IHBC

. Bungaroosh, article in the website Heritage Building Advisors.co.uk

This a definitive article verified by many experts.