If you live on a busy street where a residents’ parking permit costs nearly the same amount as a fortnight in the Maldives, then you may be tempted to turn your front garden into a parking space. You are not alone: according to a report carried out by the London Assembly, if you were to join up all the front gardens in London that have been paved over, it equates to the same area as 5,200 football pitches. Before you order a truckload of tarmac, though, there are a few things that you should consider.
Preserving the front garden is not just a matter of aesthetics.
- Flash flooding is probably the most contentious issue, where rainwater that would have steadily seeped into the soil rushes over the paving and floods into the land drains.
- Losing those precious pockets of green also significantly reduces the habitat available for wildlife.
- It lowers air quality, making city streets much hotter at night when the heat absorbed by the paving during the day is released; this is known as the ‘heat island effect’.
It is possible to create parking and still maintain a front garden, but it requires careful planning. You need to find out if there are any restrictions in your area – for example, if you live in conservation zone or a listed property – and if so you will have to apply to your local council for permission. In general, planning permission is not required if you intend to use permeable paving, but if you are using impermeable paving then the area concerned must be less than five square metres.
With permeable paving you must ensure that the sub base will also allow water to drain through – this is known as ‘open graded’. The sub base must also be of substantial enough depth to support the weight of vehicles.
The most effective way to create parking and use the least amount of paving is to lay two tracks into the garden, positioned under the vehicle’s wheels. The pavers must be suitable for vehicular use, with each track typically 300mm to 600mm in width – the wider the tracks the easier it is to drive on to them. This solution looks extremely effective if the tracks are laid into gravel or a dense matt of low planting. If you have to drop the pavement kerb in order to safely drive out into the road, the local council will have to grant permission and would carry out the work at your expense.
Here are some examples:
Things to consider when choosing permeable paving
- Gravel – this is generally one of the cheapest options but can easily scatter and is not great for use on a sloping site.
- Land-based gravel, rather than pea shingle, is larger sized and may be more appropriate, because it is less inclined to scatter.
- Reinforced grass – this is where grass is grown through a plastic honeycomb matrix. It can look effective but good ground preparation is essential and you will need to select a very tough variety of grass.
- On a heavy clay soil you may need to install additional drainage such as a soakaway, because the soil will not drain as well as a more sandy soil, making it prone to surface run-off and flooding.
- You need to keep permeable paving clear of fallen leaves, debris or soil to ensure that the water is able to drain away effectively – this is especially important with block paving where the gaps in between the paving stones can become blocked.
Words Annie Guilfoyle is a garden designer and former director of Garden Design at KLC School of Design