FOOTPATH SURFACING FULL SPECIFICATION TARMAC
1. Excavate total area to required depth and remove all waste from site,
Excavations are generally undertaken using the correct machines and the work undertaken is to excavate the required area to the correct depth dependant on the specification being used, however there are many specifications for different applications, generally domestic footpaths excavate virgin ground to a depth of 160mm for new applications.
2. Install required edging /kerb stones bedded on and backed with concrete,
There are many different types of footpath edging; however all edgings should be laid using the same specification, for domestic applications it is advised to lay them on a bed of 100mm of concrete and haunched both back and front with concrete for added support. Care must be taken in relation to the levels and all edgings must be installed to the required falls and cross falls to assist water escape on the finished surface.
3. Treat total area with weed killer and install a weed preventive and weight stabilising membrane to total area,
A suitable strength weed killer must be used to ensure against re-growth and one which will kill through to the roots, It is always advised to use a suitable strength weed and weight stabilising membrane when constructing new footpaths, one reason is to fully prevent weed growth and the weight stabilising properties will help to spread the weight of any traffic, ultimately giving a much stronger footpath surface.
4. Lay required depth of crushed foundation to form falls and cross falls to assist water escape machine rolled,
Dependant on the required specification generally for a domestic footpath applications 100-150mm of a certified MOT type crushed limestone or equivalent material should be used and must be compacted using the right weight of compactor, generally this would be a single drum roller. It is required at this point to take note when laying the crushed hard core to take into consideration the levels for the proposed water escape are in place to prevent any ponding when the footpath is complete.
5. Adjust all iron works to required levels,
Iron work relates to any manhole chambers, water/gas stop tap boxes etc. The iron works should be adjusted in height to the required finish surface level suiting the relevant falls and cross falls to assist water escape, the work would involve adjusting the height by means of hiring /lowering where required on a sand and cement mix with suitable spacing materials/ packing pieces as required.
6. Lay to total area required specification of binder and surface course tarmacadam machine rolled,
Again dependant on proposed usage the specification can differ for different applications; generally the specification for a domestic footpath would be 40mm of 20mm binder course tarmacadam and 20mm of 6mm surface course tarmacadam both materials would be laid to the required area and machine rolled using the required weight of roller.
7. Tar all joints to seal where new surface meets surrounding surfaces with hot pored bitumen.
Sealing the joints where the new surface meets with surrounding surfaces helps prevent any deterioration of the joint and also to protect against ingress of water and or any other adverse weather conditions, the sealing process is achieved by over banding the joint with a bitumous material and can be applied both hot or cold.
The above specification can be used to surface in tarmacadam to a full specification generally for new installations on virgin ground for footpath areas; however their required usage would depend on the type and depth of materials used.