All around the country setts and cobbles are becoming increasingly more popular with households as they seek to create attractive and unusual pathways and drives. The advantages of cobbles are obvious as soon as you look the finished result, they produce a magnificent effect however they are laid.
The other advantage of using granite products is the longevity you get from them, for instance our current stock of cobbles from Woolwich Docks were originally laid over 140 years ago. This compares very favourably to a modern concrete driveway which may only last 10 years, or even a stone driveway which is likely to need relaying in 25-30 years.
The vast majority of cobbles being laid in the UK today are the new, imported versions which come in from wither Portugal or China. Whilst these can look very nice in the right scenario, in our minds there is no substitute for the colour or texture you get from reclaimed cobbles, worn smooth by thousands of people walking over them.
So here are our top tips and points to consider when laying reclaimed cobbles.
Preparing the area
In many ways what the setts or cobbles are to be laid on is the most important part of the project. Traditionally the base would have been clay which would then have been topped with ash or another so called bedding material. Whilst this type of construction would have been fine for the traffic of the day, which mainly consisted of horse drawn carts, it is not suitable for modern Lorries or even cars.
The base layer is now typically made of a compacted material such a type 1 MOT or crushed hardcore. This layer should be 75-100mm thick for a pathway and 125-150mm thick for a driveway. It is also important that this layer has the same camber as the finished path will, this is to ensure that the load is evenly distributed when the path/drive is in use.
After the base layer is finished it is covered with the bedding layer, which is normally 25-35mm thick. With our modern materials the typical bedding layer is now lean mix concrete, although on small paths a 4-1 mix of sharp sand and cement can be used instead.
It is important that the bedding layer has a reasonable amount of flexibility, which will enable it to cope with the uneven sizes of the reclaimed setts.
Joint width and gauging
Joint width is a matter of personal choice, although traditionally the gap was kept quite small to make a smoother ride for the horse drawn carts and pedestrians.
Whilst this is now less of an issue, it is still advisable to use a gap of around 10mm with a 6mm margin of error, to allow for setts of differing widths. The exception to this is for use at the entrance to cul-de-sacs where a wider gap is often used with the express purpose of creating a rumbling effect to let drivers know to slow down.
The other factor to consider is the gauge of the setts, i.e. the width of the courses. Naturally this is to some extent dictated by the width of the setts that you have available, but there are also design elements to consider.
The optimal way of laying reclaimed setts is to sort the setts into piles featuring groups of setts with the same width. This then enables you to alternate course widths whilst maintaining a uniform appearance. The downside to this is the amount of time taken, but it is well worth doing if the quantities are not too great.
The alternative, and much quicker, approach is to use the setts as you come across them in the bags. The disadvantage of this approach is that the joint width tolerance will need to be increased to cope with the disparity in sizes.
Of course this is much less of an issue when using reclaimed cobbles as they are a much more regular product, and therefore can be laid with as little as a 3mm tolerance in some circumstances.
The final aspect to consider is that of channels. Used to aid drainage, these are normally 3 setts wide, although any width will work well.
If you follow these steps, then it should be perfectly possible to get a well laid path or driveway that will last for years to come.
However if you think that this could be too much for you, get in touch and we will be happy to recommend someone to help.