Cobbles & Duckstones

Introduction   Definitions   Uses   Pros and Cons   Prices   Diagram

Construction of a cobbled pavement   Setts/Cubes   Natural/York Stone   Conc. Block Paving Clay Brick Paving   Stamped Concrete

Introduction This page takes a look at the use of cobbles, gives an overview of the many terms used for cobbles, and considers their use as a paving. Construction of cobble pavements, using traditional and modern methodologies is examined on a separate page.
Definitions As with many other traditional paving techniques, this particular paving is known by a few different names in different parts of the country. Up here in the civilised part of the country, we call them duckstones or cobbles, but they are also known as cobblestones, beach cobbles, river cobbles or field stones (?!?!)
Some of the confusion arises from what many people think of as cobbles. As can be seen in the photo opposite, the rectangular blocks of neatly dressed stone, laid in regular courses are, to be accurate, setts. These are examined in more detail on the Sett Paving pages. Many folk incorrectly refer to these "setts" as "cobbles", and this is often the sort of paving imagined when one hears of 'cobbled' streets, but, to be accurate, it's the rounded, irregular, undressed, lumpy, bumpy stuff at the left hand side of the photo that are really cobbles.
Geologists and other Rock Monkeys define cobbles as 'rounded stones between 64mm and 256mm in size'. Those cobbles between 64 and 128mm are "small cobbles", while those between 128 and 256mm are, surprise, surprise, "large cobbles". Rocks bigger than 256mm are, apparently, boulders, and those less than 64mm are pebbles.

Uses and Applications At one time, many roads were 'cobbled'. Being primarily derived from river beds, beaches, drumlins or boulder clay deposits, cobbles are plentiful and well-distributed throughout the land. They could be easily set into a base of sand or loose crushed stone to provide a serviceable surface. A sett paved surface represented considerable labour in dressing the stone with hand tools prior to laying, and assumed a suitably workable stone was available locally, which was not always the case, especially in the South-East of England. Sett pavements were reserved for prestige works, the centre of busy towns or the driveways of the landed gentry. Cobbles were an Everyman's version: they provided a hard, resilient surface that could be cambered to keep it well-drained and comparatively mud-free all year round, it was fairly comfortable to walk upon (all this is in the days before stilettos or high heels!) and could be trafficked by man, beast and cart alike.

Nowadays, this type of paving is used mostly to keep pedestrians off certain designated areas, hence its categorisation as a deterrent paving. Deterrent paving refers to pavements constructed in such a way as to impede or discourage foot or vehicular traffic. In the following notes, only the use of cobbles will be discussed; for other types of deterrent paving, refer to the Special Paving page.

Cobbles used at edge of yorkstone pavement to keep pedestrians off the grass.

Cobble or Duckstone paving consists of rounded beach or river stones, generally in the size range 60 - 200mm set in a bedding matrix, which nowadays is usually a concrete or high-stength mortar. It was previously used a suitable paving for roads and tracks, and can still be found up and down the country. Although it's not really suitable for foot-traffic, as the very irregular surface makes it awkward to walk on, or push wheelbarrows or lawnmowers across, it can make an attractive hard-landscaping feature in its own right.

Consult the Construction Page for path, patio or feature use. If you're really set on using this type of paving as a drive, a concrete base layer and possibly a sub-base is recommended. All this is considered in more detail on the Construction Page.

Careful choice of the stones used to construct a cobble pavement can determine whether it acts as a usable, if slightly uncomfortable, surface, or an ankle-snapping, pram- and trolley-proof, deterrent. Originally, most cobbled surfaces were laid to be an improvement on an unmetalled surface, ie, mud and puddles. The stones were laid tight to their neighbours, with flat surfaces uppermost. This role was gradually usurped by dressed sett paving, and now cobbles are often relegated to providing a cheap infill or feature paving, or a "KEEP OFF" paving.
Cobbles chosen for flat upper surface and laid tight to neighbours and fairly flush to create a walkable surface	Cobbles chosen for colour and shape, laid three-quarters buried as a garden feature (allegedly!)	Cobbles laid with plenty of upstand and wide separation to create a deterrent.

Pros and Cons Compared with other forms of paving, cobbles are moderately priced. However, they are time consuming and labour intensive...just arranging the stones into a reasonable pattern is like solving a jigsaw, but the actual laying work is not technically demanding, and can be undertaken with basic DIY tools. Contractors asked to undertake this type of work will often charge for their time, rather than by the area, Be aware that the skills needed to make a decent job of laying cobbles are not the same as those required to lay block paving, and some so-called "Paving Specialists" will never have laid this type of work before. Ask to see work of similar nature before awarding the contract. Sadly, cobbles have limited uses nowadays. They can be used more effectively as a hard-landscape feature, such as around ponds or statuary in the garden.

Cobble paving is very low maintenance once laid needing little more than the occasional sweeping with a stiff brush to remove dust and detritus. If you find green algae building up on them, it can be removed by a pressure washer or a brush and water. Swilling the area with Jeyes Fluid or Armillatox is said to kill the algae, which can then be swept away after a couple of days. Properly laid, cobbles should easily outlast longer than any of us!

Price guide

How these prices were calculated: Skip(s) to remove excavated material from site 75mm thick bedding concrete and suitable cobblestones Labour Driveway includes additional 75mm thickness of concrete bedding as base layer Access Road includes additional 75mm thickness of concrete bedding as base layer, plus 100mm sub-base of DTp1 Also included hire of electric mixer for 3 days or 1 weekend. All prices include VAT and are intended for guidance only. Prices vary throughout UK - consult your local suppliers. Prices reviewed April 2002

Construction Diagram

See Construction Page for fuller explanation of this diagram