Eco driveways: create green off-street parking
Having off-street parking can have a serious impact on the environment, if you don't build by the rules...
Most people who want off street parking, simply turn their front garden into a driveway. In the past, most people would lay down what is described as a hard standing' -ie paving stones, concrete, crazy paving or tarmac - to enable them to park their cars on it.
This might be great as a car-parking surface, but it can be damaging to the environment. Research done by the Greater London Authority showed that a fifth of London was made up of private gardens. If you simply destroy huge numbers of front gardens, replacing them with paving stones, the scope for birds, plants and insects is dramatically reduced.
In addition, there is the problem of water run-off. If you lay concrete in front of your house, the rain water has to go somewhere. Instead of soaking into the ground, it will simply run straight into the drains. At times of heavy rainfall this puts a huge burden on drains and sewers, which can often overflow. This can result in an increased number of flash floods.
Concrete drives can also cause subsidence. If a front garden is replaced with a hard standing, water will no longer get into the soil. This means that the soil under the street tends to dry out more readily. In areas with a clay subsoil - ie virtually all of London - this can lead to earth movement and subsidence.
The problem of subsidence is aggravated because hard standings make it hard for trees to get water directly from the soil. As a result, the trees have to put out larger roots to get the water that they need. These extensive roots can disrupt water mains and water cables. As they push outwards, the roots can get under houses and weaken the foundations.
Until recently there was nothing to stop people from paving their front gardens for use as driveways. However since the beginning of October 2008, there have been new rules for anyone wanting to put a hard standing at the front of their house. These rules only apply to the land between the front boundary of your property (this will usually be your garden wall) and the level where the house itself begins. If you want to replace an old hard standing or install a new one at the front of your house you will require planning permission. The only exception is where the area is very small - under five square meters.
However you are allowed to install a permeable surface - ie one where the water can run through the soil - without planning permission. So you can install a gravel drive - as long as it has a permeable base underneath. Or you can install permeable concrete block paving, or you can install some kind of grass system - grass laid on a heavy duty plastic mat.
You can even put down concrete tracks to accommodate the wheels of your car, with grass or plants between the tracks. This is perfectly alright, as long as the total area of concrete does not exceed five square metres. Remember that although these rules mean that you are allowed to lay down a permeable surface on your front garden, you will still need permission to use this area as a driveway.
Further information is available from the Environment Agency document - Guidance on the Permeable Paving of Front Gardens - downloadable from www.communities.gov.uk
Interpave - the trade association for paving manufacturers - also have advice and booklets online on www.paving.org.uk