When we moved into our house there was no driveway at all – instead the front of the house was occupied by a pretty cottage garden. However, with two cars and two toddlers, we really needed to be able to park outside the house so we set about formulating some driveway ideas and removing the garden.
The road our driveway leads off sits at a higher level, meaning the access into the driveway is pretty steep. While this isn't a huge issue, it does mean that my son and husband's cars, which are both on the low side, often get scraped underneath, particularly if there are passengers in the back adding to the weight.
We are hoping to expand the driveway later this year by removing part of the hedge that separates it from the road and I'd like to look into whether we might be able to build it up slightly to reduce this slope at the same time. I asked the experts what the job would involve, whether it is feasible and how much I might have to budget.
Article continues belowHow steep is too steep for a driveway?
Sloping driveways are not at all uncommon, but in cases where they are very steep, or when homeowners are looking to turn a sloping front garden into a driveway, it is important to realise that there are certain guidelines to take into consideration before any kind of excavation work begins.
Guy Wall, head of marketing at GCL Products explains. "For vehicular access, local authorities generally recommend a driveway to be no steeper than 1:10. Some local authorities will not approve a crossover, or dropped kerb (where vehicular access crosses a pavement) where the hardstanding has a gradient of 15% (around 1:7) towards the highway, so it is worthwhile checking with planning at the local authority before beginning to understand exactly what the requirements may be.
"When looking at paving options, drainage guidance commonly works to falls of up to around 1:60, depending on what the intended purpose of the surface is," adds Guy.
Guy has extensive knowledge on sustainable drainage, gardens and landscaping as well as some interest and experience in solar and renewable technology. Resin bound gravel, wet pour rubber surfacing and permeable surfacing are his specialities.
What should you do before levelling a driveway?
Before getting started on this undertaking, it is important to weigh up the pros and cons, as well as to check whether or not driveway planning permission will be required.
In most cases, providing your driveway plans fall within permitted development criteria, such as using permeable driveway materials if your driveway will be over a certain size, permission will not be required. If you are creating or altering a dropped kerb, you will need to apply for highways consent.
It isn't just permissions you need to be concerned about at the initial stages though, as Guy Wall explains. "Probably the most important factor in levelling a sloping driveway is practical planning. Failure to plan correctly could cause structural issues, not just to the driveway but to nearby properties too.
"The gradient should be measured to help assess the level of work required to level the driveway, plan for drainage and help ascertain whether this is going to be a large or small scale project. Levelling a slope can be a significant undertaking so you need to know what you are stepping into."
What does levelling a sloping driveway involve?
Unlike certain exterior home makeovers, levelling out a sloping driveway causes a considerable amount of disruption, depending on how sloped the site is – being prepared for this is very wise.
"In practical terms, levelling a sloping driveway usually involves a cut-and-fill approach," picks up Guy Wall. "That means excavating higher ground, building up lower ground, or using a combination of both to create a safer and more usable finished level. On shallow slopes this may be fairly straightforward, but on steeper sites, the volume of spoil, the need for imported sub-base, and the challenge of holding the new levels in place can increase quickly. This is often the point where a seemingly simple driveway job becomes a more substantial groundworks project.
"Once the levels are set, the sub-base has to be built properly to support the new profile," continues Guy. "This is one of the most important parts of the job, because a driveway on a slope will be exposed to vehicle loading, braking forces and water movement. If the foundation is poor, the surface is far more likely to dip, rut or settle unevenly. The steeper the driveway, the less forgiving bad groundwork becomes."
Drainage and structural considerations
In our case, the issue is that the driveway is much lower than the road, meaning we would need to build it up rather than excavate. Either way, you need to give some consideration to how the new levels will be supported, as well as to ensuring adequate drainage methods are put into place.
"If the driveway is being cut into a bank or built up above surrounding ground, some form of edge restraint or retaining structure may be needed," explains Guy Wall. "On milder gradients this may be as simple as robust kerbing or edging. On more significant level changes, it can mean low retaining walls or other structural support like piling. This is a key design point, because the driveway edges often do the hidden work of keeping the whole build-up stable."
Guy goes on to explain that driveway drainage becomes more important than ever in the case of sloping sites. "Drainage is one of the biggest issues with sloping driveways, and it cannot be treated as an afterthought. The driveway needs controlled falls so water does not sit on the surface or run towards the building. UK guidance for front garden surfacing says the driveway should slope away from the house where possible, and if it slopes towards the house a drainage channel should be used to collect water before it reaches the property.
"Where the driveway cannot simply shed water into a permeable area within the plot, the drainage solution may include channel drains, a driveway soakaway or a permeable construction that manages water on site," continues Guy. "It is also worth remembering that in England and Wales, surface water from driveways should not normally be directed onto the public highway unless planning permission has been granted. Alternatively, using permeable paving as the wearing course will help to reduce or eliminate runoff."
How much does it cost to level a driveway?
As you might expect, just as with costs for a new driveway, what you end up paying to level a drive are very much hinged on the site in question and how much work is going to be required.
"A full re-grade and resurface is the most thorough fix," picks up Chartered Architectural Technologist Zaeem Chaudhary, director of AC Design Solution. "This is where the existing surface is broken up, the sub-base cut down or built up to create a gentler gradient, and a new surface laid. When taking this route, the most expensive part tends to be the removal and excavation of the earth.
"Costs for this can range from £8,000 – £20,000+," continues Zaeem. "Ways to reduce these costs would be to use tarmac which is cheaper than than block paving or resin, but doesn't result in the best looking driveway."
Zaeem Chaudhary, MCIAT is director of AC Design Solution, a multidisciplinary practice delivering architecture, structural engineering and party wall services across London and the UK
FAQs
How long does it take to level a sloping driveway?
Timescales for levelling a driveway very much depend on the complexity of the work as well as the size of the space you are working with and the driveway design you have opted for.
"A simple driveway regrade may be done in under a week, but more complex sloping sites that need excavation, retaining work and drainage can take much longer," says Guy Wall. "The timescale depends less on the finish and more on the extent of groundwork underneath."
The driveway materials you choose to finish your new driveway need really careful consideration. Not only will they determine whether or not planning permission will be required, but they will also define its look, how much maintenance is required and what you end up paying overall.
