How do I lay gravel so it does not sink or spread?

The sub-base, edging and depth that make a gravel path or drive stable, and why most gravel problems are depth and edging rather than the stone itself.

Difficulty: intermediate
Time: 6 hr
Read: 4 min

Short answer

Excavate, lay a compacted sub-base, put a permeable membrane over it, add an edge that holds the gravel in, and finish with no more than about 50mm of angular gravel. Deep gravel is why it feels like walking on a beach; angular stone is why it locks together.

Gravel that sinks, spreads and grows weeds nearly always has three things wrong with it: no proper base, no edging, and too much of it. Fixing those makes the difference between a surface that lasts fifteen years and one that is a nuisance from the first month.

What you'll need

Spade or hired mini-digger
Compacting plate or hand rammer
MOT type 1 sub-base
Permeable geotextile membrane
Edging
Angular gravel, 10 to 20mm
Gravel stabilisation grid (optional)

Step by step

Excavate deep enough.About 100 to 150mm for a path, and 200mm or more for anything vehicles will use. Remove all vegetation and topsoil.
Check drainage and permeability rules.New hard surfaces at the front of a house over 5 square metres need to be permeable or drain to a soakaway. Loose gravel over a permeable build-up satisfies this; solid resin-bound or concrete may not.
Lay and compact the sub-base.MOT type 1 in layers no thicker than about 75mm, each compacted with a plate compactor. This is what carries the load and it is the part people skip.
Lay a permeable membrane.Over the compacted sub-base, overlapped generously at joins. It stops gravel migrating down into the base and stops weeds coming up. It does not stop weeds germinating in debris on top of it.
Install a proper edge.Timber, metal, brick or a proprietary gravel edging, set to the finished height. Without an edge the gravel spreads into borders and lawn within a season and never stops.
Choose angular gravel, not rounded pea shingle.Angular stone of 10 to 20mm locks together and stays put underfoot. Rounded pea shingle rolls and never firms up, which is why it feels unstable.
Keep the depth to about 50mm.Any deeper and it never consolidates. This is the single most common mistake, and it makes a path unpleasant to walk on and impossible to push a wheelbarrow over.
Use a stabilisation grid for drives and slopes.Honeycomb panels filled with gravel hold it in place completely, take vehicle weight and stop rutting. Essential on any slope.
Rake it level and let it settle.Rake to an even depth and leave it. It consolidates over a few weeks of use and rain, and can be topped up lightly afterwards.
Sweep and top up annually.Remove leaves and debris before they rot into a seedbed on top of the membrane, and add a thin top-up where it thins out at turning points.

Tips

50mm of gravel, no more. Deeper is the reason it feels like a beach.
Angular gravel locks together; rounded pea shingle rolls forever.
The edging is not decoration — without it the gravel migrates into the borders within a year.

Common mistakes

Laying membrane straight onto soil and tipping gravel on top — With no compacted sub-base it sinks into the ground, forms ruts and puddles, and the membrane works its way to the surface. The base is most of the job.
Laying 100mm of gravel for good coverage — It never consolidates, it is difficult to walk on and impossible to barrow across. 50mm over a proper base gives full coverage and a firm surface.

If it doesn't work

Gravel sinking into the ground

Cause: No compacted sub-base or no membrane — Fix: Lift, excavate properly, lay and compact type 1, then membrane and gravel.

Gravel spreading into beds and lawn

Cause: No edging — Fix: Install a proper edge at the finished gravel height.

Feels like walking on a beach

Cause: Too deep, or rounded pea shingle — Fix: Rake out the excess to about 50mm, and consider replacing with angular stone.

Weeds growing in the gravel

Cause: Debris rotting down on top of the membrane — Fix: Rake and sweep regularly. Membrane only stops weeds from below, not seed landing on top.

Questions people ask

How deep should gravel be?

About 50mm over a properly compacted sub-base. Deeper never consolidates and makes the surface unpleasant to walk on and impossible to wheel anything across.

Does membrane stop weeds?

It stops weeds growing up from the soil below. It does nothing about seed landing in the debris that accumulates on top, which is where most gravel weeds actually germinate.

What gravel should I use?

Angular stone of about 10 to 20mm, which locks together and stays put. Avoid rounded pea shingle for paths and drives — it never firms up and rolls underfoot.