Tarmac driveways in the Stort Valley and East Herts

What is a tarmac driveway?

Tarmac, more correctly called asphalt or bitumen macadam, is crushed stone bound with bitumen. It is laid hot, spread to an even depth and rolled flat while still warm. It gives a firm, dark, continuous surface that copes well with cars and is quick to lay over large areas, which is why it is common on long drives, farm entrances and shared accesses as well as town frontages.

A drive is usually built in layers: a compacted stone sub-base, a coarser binder course and a finer surface course on top. The thickness of each layer has a bigger effect on how long the drive lasts than the colour or finish.

Does a tarmac drive need planning permission?

Standard tarmac is not permeable. Water runs across it rather than through it. On a house's front garden, a new or replacement surface of this kind covering more than 5 square metres needs planning permission unless the rain is directed to a permeable area inside your boundary, such as a lawn, a gravel strip or a soakaway.

Two ways round this are common:

• Laying the tarmac with a fall towards a border, a planted bed or a channel drain that empties into a soakaway.
• Using porous asphalt, which is made with gaps between the stones so water drains through to an open base.

The Planning Portal explains the front garden rules on its paving your front garden page. Separate rules apply to flats, maisonettes and listed buildings.

Can tarmac be laid over my old drive?

An overlay is sometimes possible where the existing base is firm and level and the problem is only a worn top. It raises the surface, though, so it needs care beside the house wall, at the gate and where the drive meets the pavement. The finished level should stay well below the damp-proof course, and doors and garage thresholds need to open freely.

If the old drive has sunk, cracked badly or holds puddles, digging out and rebuilding the base is the more lasting answer.

What happens during the work?

• The area is marked out, and buried pipes, cables and drains are located before digging.
• The old surface is broken out and taken away, and the ground is dug to depth.
• Edging is set in place to hold the tarmac.
• The sub-base is laid and compacted.
• The binder and surface courses are laid hot and rolled.

Ask how long to keep cars off the new surface, because fresh tarmac can mark under a turning wheel or a parked jack.

What are the downsides of tarmac?

In hot weather, new tarmac can soften slightly and show tyre marks or dents from motorbike stands and skip feet. Petrol and oil spills can damage it. The colour fades from black to grey over time. Some people find a plain tarmac drive looks stark against an older house, so a contrasting border of blocks or setts is a popular addition.

What about trees near the drive?

Digging close to a tree can damage the roots that hold it up and feed it. If a tree on your land or a neighbour's is protected by a tree preservation order, or stands in a conservation area, you may need to tell the council or get its consent before work that could harm it. The government's guidance on tree preservation orders and trees in conservation areas explains what is covered. Roots can also lift tarmac in later years, so the layout around a tree needs thought.

Is tarmac a good fit for a long country drive?

It is one of the more practical choices for a long or shared drive, because it can be laid quickly over a large area and gives a firm surface for heavier vehicles such as delivery vans or oil tankers. On a rural drive, where the water goes matters just as much as in town. Rain running down a long tarmac slope onto a lane can wash grit onto the road, so a cross fall towards a planted strip within your land, or channels feeding a soakaway, are often part of the design.

What details help with a tarmac enquiry?

• your postcode and whether the drive is in town or out in the country
• a rough length and width, or a sketch of the shape
• what is there now and any problem areas
• whether water collects anywhere after rain
• whether you need a dropped kerb as well

What happens after I send it?

Enquiring is free and leaves you under no obligation. Anything you go ahead with is arranged and priced by the installer.