Permeable driveways

Why it matters for planning

• You don't need planning permission for a new or replacement driveway of any size if it uses permeable (porous) surfacing^[1].
• If the surface isn't permeable and covers more than five square metres, you will need planning permission^[1].

• Planning rules

Ways to make a driveway permeable

The government's guidance names three main ways to make a driveway permeable: gravel or a mainly green area, sending water from a hard surface to a rain garden or soakaway, or using permeable block paving, porous asphalt or concrete^[2].

• Gravel
• Block paving
• Resin

What goes underneath

The government's guidance says permeable driveways need open-graded sub-base materials that let water through and store it, giving 4/20 and Type 3 sub-base as two examples^[2].

On very clayey soils that cannot soak up much water, the government's guidance calls it a wise precaution to include a pipe in the sub-base to drain water to the roof drains^[2].

When permeable surfacing may not suit

• The government's guidance says a drive steeper than 1 in 20 may not be suitable for permeable surfacing^[2].
• The government's guidance says not to build rain gardens or soakaways close to building foundations, and that for small driveways a minimum distance of 3m should be suitable, though it depends on the ground conditions^[2].

What it costs

• Checkatrade's UK cost guide says a concrete permeable driveway costs around £80 per m² on average^[3].
• Checkatrade's UK cost guide says a resin permeable driveway will cost about £60 per m²^[3].

These are national guide figures, not Doncaster quotes. Ask each installer to price the same surface and the same sub-base so the quotes compare like for like.

Checking the work and looking after it

• Once the paving is finished, the government's guidance says a hosepipe turned onto the surface for 1 or 2 minutes should leave no puddles, with the water soaking straight in^[2].
• The government's guidance advises cleaning up leaves, mud and litter before they have a chance to clog a permeable surface^[2].
• If the surface does block, the government's guidance says porous asphalt and permeable concrete blocks can be unclogged with a small vacuum road sweeper or a jet washer^[2].

Choosing who builds it

• Is the whole build-up permeable, or only the top surface?
• What sub-base is in the quote, and how deep?
• Where does the water go if the ground below drains slowly?

The government's guidance says casual contractors who knock on your door and offer to lay a driveway should not be used to build permeable driveways^[2].