The key is drainage - if you use a porous material, such as gravel, permeable asphalt or permeable block paving, you won’t usually need planning permission.
Nor will you if the off-street parking is constructed to allow rainwater to drain to a border or lawn.
However, if you’re covering an area of more than five square metres in an impermeable material and rainwater won’t be able to drain to a permeable area, planning permission will be required.
To read more follow the link below http://home.bt.com/lifestyle/house-home/diy-ideas/convert-your-front-garden-into-a-drive-11364095907842
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