10.2.6Drives, paths and landscaping
Appropriate access (including private roads, shared private drives, private drives, car parking and paths) shall be provided to and around the home. Issues to be taken into account include:
- general construction considerations
- drainage
- construction details
- minimum sub-base thickness
- house paths and patios.
Homes should be provided with suitable access through the provision of private roads, shared private drives, private drives, car parking areas and paths, as appropriate.
Private roads, shared private drives, private drives, car parking areas and paths should comply with relevant building regulations. Where abutting the home, they should be at least 150mm below the DPC, and laid to falls away from the home (unless a channel or other suitable means of collection and disposal is provided).
All vegetable matter should be removed from the area of the proposed works.
Only suitable fill material comprising clean, well-consolidated crushed rock, hardcore, slag or concrete should be used to make up levels.
Sub-bases should be mechanically consolidated in layers not exceeding 225mm.
Finished ground levels should be compatible with:
- DPC levels
- cover levels of drainage access points
- depth of underground services (gas, electricity, water and drains)
- adjacent surfaces.
- be appropriate for the loads
- provide reasonable access to and from a garage or car parking area
- have a maximum gradient of 1:6
- where the gradient is more than 1:10 and the gradient changes, have suitable transition lengths to reduce the risk of vehicles grounding.
- Where entry to the home can be gained directly from a garage, a path to a secondary access door is not required.
- Where the secondary entrance is to a mid-terrace home or ground floor flat, a path to a secondary access door is not required.
- Where a garage, carport or car parking area is provided within the curtilage, a path should be provided to it from the home.
- have vertical alignment, finished levels, transition arrangements and gradients in accordance with the design
- have surfaces with adequate falls, cross-falls and drainage to ensure that surface water is suitably drained
- have sub-base levels with the same longitudinal gradient and cross-fall as the finished level
- have surfaces not flatter than 1:40 or have a camber of 1:40 where no fall is available to avoid ‘flat spots’
- have surfaces with a minimum finished fall of 1:80 where they form private drives and paths
- drain away from the home (and garage), or drain to a channel or other suitable means of collection and disposal adjacent to the home
- not drain surface water from private areas onto adopted areas
- not be within 2m of a soakaway.
- CBR value
- frost susceptibility of the sub-grade; where susceptible to frost, a suitable capping layer should be included below the sub-base to a suitable depth to ensure that the construction will not be affected by frost heave.
- Granular sub-bases should be tested and certified as being non-frost susceptible and non-plastic.
Private roads, shared private drives and private drives should:
Underground drainage or services that are below a private road, shared private drive, private drive, car parking area, path or patio should be protected against damage, as described in Chapter 5.3 ‘Drainage below ground’.
Edge restraint or kerbing should have a profile and foundation, which is suitable to form a permanent supporting edge for the expected vehicle loads on the road or drive.
Pedestrian access should be provided via a path within the curtilage of each home to the main entrance and the secondary entrance where present:
Where appropriate, a drive can be regarded as a path for the provision of access.
Paths should have a maximum slope of 1:6. On steeper sloping ground, steps may be required.
| Location and use | Minimum width of hard standing (mm) | Minimum overall width (mm) |
|---|---|---|
| Within curtilage to main entrance, or any entrance designated by Building Regulations. | 900 | 900 |
| Paths used for the removal of refuse to the collection point. | 750 | 900 |
| Paths adjoining a home (with hard standing 100mm or more from the wall of the home). | 450 | 700 |
| All other cases. | 450 | 600 |
Private roads, shared private drives and private drives should have adequate rainwater drainage and disposal.
Paved areas should:
Where paving slabs are laid abutting drainage channels and gully grates, etc., the upper surface of the paving slab should be set approximately 5mm above the grating.
Where it is intended to use porous or permeable surfaces as part, or all, of the rainwater drainage system, reference should be made to CIRIA report C753 - The Sustainable drainage system (SuDS) manual.
The construction of private roads, shared private drives, private drives and car parking areas should be constructed in accordance with the tables below and/or other published/approved design procedure.
Notes
1In the first column, European harmonised names for the pavement layers are with the old UK designations included in brackets.
2Where a capping layer is specified, sub-base thickness can be reduced. Pavement Design CD 225 Revision 1 gives guidance on capping and sub-base thickness design based on CBR values with and without a capping layer.
3For the minimum thickness of the sub-base for different CBR values, refer to Table 3.
4Bond coat in accordance with BS 594987 should be applied to ensure effective bonding of the asphalt layers.
5Bituminous mixtures/asphalt can be used as a partial replacement of a full thickness granular sub-base type 1 material.
6 If the binder course is subjected to an extensive period of trafficking before the surface course is applied, a recipe mixture containing a higher bitumen content will be more durable/resistant to fretting/ravelling under traffic.
7Where laid to either a 90 or 45 degree herringbone pattern, the edge perimeter should be laid with one single row of stretcher bond set parallel to the edge restraint. Where block pavers are laid abutting drainage channels, gulley grates, etc. the upper surface of the block pavers should be set 3-6mm above the grating. Manufacturer’s declared value markings W3 and S4 are acceptable. Where W3 is 1.0kg/m2 or less and S4 is 45 or more based on ‘C scale unit’ (for abrasion, class A2 = maximum result is 23mm, class A1 = no performance determined).
8A 38mm thickness of graded 15/20mm unbound aggregate to BS EN 13242 (gravel), well rolled and compacted, should be used.
9Reference to clauses are in relation to the relevant European and/or British Standards.
10Asphalt contractors should be certified in accordance with the National Highway Sector Schemes for Quality Management in Highway Works - Scheme 16.
The thickness of any required capping layer and the sub-base should be determined after investigations and on-site tests have been carried out, with consideration to the:
Notes
1Minimum thickness of sub-base may be considered for reduction when using proprietary geogrid, provided they can be adequately justified and designed by an Engineer in accordance with Technical requirement R5.
2Specialist advice should be sort to improve the subgrade.
The following construction will be generally acceptable for house paths and patios:
The sub-base comprising of a 100mm thickness of clean, non-frost susceptible well consolidated crushed rock, hardcore (maximum size 50mm), slag or concrete, the surface of which is blinded with 25mm of sand.
Paving slabs fully bedded in 25mm 1:4 cement/:sand mortar or a suitable alternative.
Concrete paths and patios should be not less than 75mm thick and have a tamped or textured finish. The concrete mix should be suitable to give a durable and frost resistant surface, as described in Chapter 3.1 ‘Concrete and its reinforcement’. Movement joints, not less than 10mm wide, should be provided across the full width of the path at not more than 4m centres. A movement joint is not required at the abutment with a wall unless the opposite edge of the concrete is also restrained.
