Stone cobbles are hand chiseled natural stones which are environmentally sound, recyclable, non-slip, everlasting and require almost no maintenance. The size of cobbles lie between a boulder and a pebble. They can be put to innumerable uses and are generally used for pavements, outhouses and pool sides.
Cobbles are widely used for decorative purposes due to its natural beauty. They can be mixed with flagstones and stepping stones as border detail or divisions between pave areas for a great decorative effect.
Cobbles Laying Patterns
Cobbles can be laid in one of the following patterns:
Random Work: The cobbles are more or less packed together and are laid randomly. It is the lowest grade work.
Flat Parallel Work: Cobbles are laid in rough lines but since they are of different sizes and shapes they can deviate form true lines.
Coursed Work: Cobbles are sorted into similar sizes and then laid in straight lines that are either longitudinal or transverse. It is the highest grade work.
Cobble Construction
There are two main types of cobble construction that are used today - cobbles as a pavement that will be trafficked and cobbles as a deterrent surface. The main difference between the two is the spacing and depth of embedding of the cobbles.
Steps of Construction
Dig the surface. The depth of dig can be calculated as:
Dig Depth = Stones + Bed + Base + Sub Base, here base and sub base are optional depending on the type of construction.
All the unwanted organic matters are removed.
A base layer is laid as a separate layer for pavements. The base layer may be any bound material like Bitmac or Concrete.
The cobbles are then bedded onto a bed of mortar or concrete.
They are pushed into the bedding concrete, to at least half their depth.
For trafficked areas keep spacing of the stones as tight as possible and use smaller cobblestones to fill spaces in between. They are placed with the flattest face upwards.
For deterrent paving lay the cobbles at intervals. They are generally placed with pointy end up.