Advice
RHS Help & Advice
Permeable hard landscaping
Heavy rain runs off impervious surfaces such as concrete and paving, increasing the risk of flash flooding. Porous materials that allow water into the soil reduce this danger.
Gravel
A cheap and easy to use material, especially when laid onto a permeable weed barrier fabric. Use a heavier grade fabric and larger gravel size for areas that will carry a greater load, but remember that larger sized gravels are awkward to walk on. Gravel can also be used between other materials such as paving slabs or stepping stones.
Cellular paving
A wide range of ‘honeycomb’ matrix paviours are available which can be infilled with gravels, shredded tyres or recycled glass chips, but avoid resinous bonding products as these may result in an impermeable surface.
Grass reinforcements
Both concrete and mesh are available. The best results are where the lawn is sown into the reinforcement material, but some types can be placed onto existing lawns.
Brick paviours
Dry-laying bricks enables water to penetrate between them (though in wet periods some surface run-off can occur). Any weed-proof fabric or membrane laid below the aggregate must also be permeable.