Tar & Chipping Drives Cambridge
Granite or other decorative chippings can be used on a driveway in place of shingle and can look stunning.
At RJS Landscapes we offer a wide range of decorative chippings for use on driveways. We will ensure the foundations of the driveway are solid, so you can have peace of mind as to the quality of the driveway.
We only buy our chippings from recognised suppliers therefore, offering a unique high standard product. Simply incorporating edging or granite sets can help retain the aggregate as well as enhance the appearance of the driveway.
What is it?
Two layers of bitumen emulsion and stone chippings on top of a Type 1 granular sub base on geotextile in a formation tray. This bound surface is commonly referred to as ‘tar spray and chip’, but its correct surfacing term is ‘surface dressing’. It can also be directly applied to an existing worn bitmac or asphalt surface, to add surface texture and grip.
How does it work?
Surface dressing creates a stable mosaic of stone chippings, securely attached to the surface by a bitumen emulsion. Quite simply, the bitumen emulsion glues the stone chippings to the surface. The chippings may look loose, but are firmly held in place by the bitumen.
What are the benefits?
Surface dressing is generally applied on worn road surfaces to reduce the risk of skidding. For paths and a more country/rural driveways, it can provide a number of benefits:
- It changes the colour of a ‘black’ Tarmac driveway and helps to lessen its visual impact. The finished look depends on the colour of the stone chippings used.
- It creates a non-slip surface for most driveway or path users, improving grip for horses, cars and skid resistance for cyclists.
- It restores surface texture and seals minor cracks in a worn Bitmac, Tarmac or Asphalt surface. This protects the path or driveway base against the ingress of water, slows down the deterioration and prolongs the life of the drive.
- It keeps maintenance costs reasonably low.
Is it suitable?
Surface dressing only works on well-compacted sub base surfaces that are smooth and even, because the finished surface treatment is thin. It is liable to crack if the sub base surface is loose and uneven. The time period available for laying surface dressing is very narrow, only the summer months are really suitable, as there can be a risk of surface failure when temperatures are low. It also needs to be laid by experienced surfacing contractors, who are proficient in its application.
How much will it cost?
As each project is different we would prefer to visit the site and talk you through the options before quoting. Call us and we will make an appointment to access your Driveway or Path.
How do you install it?
Surface dressing involves either single surface dressing or double surface dressing over a prepared surface, such as a sub base, worn Tarmac or Asphalt. If applied directly to a sub base, two layers of surface dressing are required to make a durable surface. On top of an existing worn Tarmac or Asphalt surface, one layer of surface dressing is adequate.
Before laying surface dressing, treat the new sub base or existing worn Tarmac or Asphalt surface with weed killer – weeds may break through the thin surface and crack it. Use a residual weed killer subject to environmental considerations.
Surface dressing quality depends on the evenness of the surface that it will be applied to. It is important to specify a surface regularity of a maximum gap of 10mm under a 3m straight edge with no high or low points or hollows. If possible, use a drag box to lay the sub base to achieve an even surface. If the sub base lacks sufficient fines to provide an even surface, blind it with a dust. If ‘as dug’ or recycled aggregates are to be used to build the sub base, regulate with 50mm depth of Type 1 to provide a strong, even surface that is suitable for laying the surface dressing on.
Before use, loose stone chippings must be swept from the finished surface. Loose stone can cause a slip hazard.
Here is a useful link of a detail drawing