Road Planings for a Driveway: What They Are and How They Compare

Every time a road is resurfaced, the old surface is milled off, and that crushed tarmac is what gets sold as road planings. Spread and compacted, they make a cheap, firm track that partly knits together as the old bitumen in them settles under traffic. They suit farm tracks, field gateways and rough back yards well. On a house driveway they are a budget compromise: dusty and loose at first, prone to ruts and potholes, and nowhere near the finish or life of properly laid tarmac driveways.

What are road planings?

When a council or contractor resurfaces a road, a planing machine grinds off the top layers. What comes out is a mix of stone and old bitumen in pieces from dust up to small lumps. Some is recycled back into new asphalt at the plant; asphalt is fully recyclable. The rest is sold on as a cheap fill and surfacing material, often called tarmac planings, road scalpings or recycled asphalt.

Because planings are reclaimed from different roads, quality varies. A good load is consistent in size and mostly bound material. A poor load can contain lumps, soil, kerb fragments and rubbish.

How does a planings driveway bind together?

Planings are not a bound surface in the way a hot tarmac drive is. They rely on three things:

• Compaction. Rolled or plated in layers, the angular pieces lock together into a firm mat.

• Residual bitumen. The old bitumen coating on each piece can soften slightly in warm weather and stick neighbouring pieces together, which is why planings tend to firm up through their first summer.

• Sometimes a binder. Some installers spray a bitumen emulsion over the compacted surface to help hold the top together.

Even well compacted, the top layer stays partly loose, and the surface keeps shedding small stones where tyres turn.

Road planings driveway: the advantages

• Cost. Planings are much cheaper per tonne than new hot tarmac, and there is no hot-mix delivery to time.

• Firm and quick. Laid over a decent base, a planings surface takes traffic immediately.

• Good for long, rough runs. Farm tracks, paddock gateways and yards where looks do not matter are where planings make most sense.

• Recycled material. Using reclaimed asphalt keeps it out of landfill.

The problems with planings on a house drive

• Loose surface. Stones and grit migrate onto paths, into the house and into the road.

• Ruts and potholes. Without a binder course and a bound surface, wheel tracks and turning areas wear into hollows. Puddles then speed things up.

• Edges. Like any bitumen surface, planings spread at the edges unless held by kerbs or edging.

• Weeds. A thin or patchy layer lets weeds root through.

• Appearance. The finish is grey and uneven rather than a smooth black surface, and it never looks like a laid drive.

• Drainage. How a planings surface drains depends on how tightly it is compacted and the falls. It should not be assumed to count as a permeable surface for the front-garden rule without proper design.

Are road planings legal to use?

Road planings are normally treated as a waste in England unless they qualify as a product. The Environment Agency's U1 waste exemption lets you register to use waste such as road planings to build tracks, paths and car parks, up to 1,000 tonnes over the three-year registration period, as set out in the U1 exemption guidance on gov.uk.

There is also a contamination issue. Tar has not been used in asphalt since the 1980s, but roads built before then can still contain road tar layers. Highways guidance from ADEPT says road tar must be considered a carcinogen, and that where there is not enough information about what is in road arisings, they must be assumed to be hazardous. If you are buying planings, ask the supplier where they came from and whether they have been tested.

Planings vs a laid tarmac driveway

The difference is structural, not just cosmetic. A laid tarmac drive is built in layers: a compacted crushed stone sub-base, then a binder course of around 50mm, then a surface course of around 20-25mm, all hot-mixed and rolled while hot. Each layer is designed for its job. A planings drive is usually one layer of reclaimed material doing all of those jobs at once.

That shows up over time. A properly laid tarmac drive typically lasts 15 to 20 years before it needs resurfacing. A planings surface tends to need topping up and re-rolling in the areas that see most traffic. For a long farm track, that trade-off can be worth it. For a front drive you see every day, most people end up wishing they had paid for a bound surface.

Can you lay tarmac over road planings?

Sometimes. A well compacted, well drained bed of planings can act as part of a sub-base, but it is not a substitute for a properly graded crushed stone sub-base under a new drive. Any loose, contaminated or rutted planings layer needs digging out first. Whether an existing surface can take a new layer is the same question we cover in our post on driveway resurfacing.

Road planings questions, answered

Do road planings go hard?

They firm up with compaction and warm weather, as the old bitumen softens and binds the pieces together. They do not set like hot tarmac, and the surface stays partly loose.

How deep should road planings be?

Installers commonly lay them in compacted layers rather than one thick lift, because compaction does not reach the bottom of a deep loose layer. They still need a firm base underneath; planings over soft ground will rut.

Are planings the same as tarmac?

They are old tarmac, broken up. Our post on what tarmac is made of explains the materials; the difference is that planings are no longer a bound, engineered layer.

Looking for a drive that stays put?

If you want a firm surface for a back yard or a long track, planings may do the job. For a front drive in Wolverhampton, the Black Country or south Staffordshire, a properly laid tarmac or concrete drive is the longer-lasting answer, and Pete and the team can talk you through both. Ask us for a free quote.