Tarmac Driveways

"Tarmac" is a general name used for bitumen-bound driveway surfaces. There are two main types:

• Macadam (what most people call tarmac): Graded stone bound together with bitumen. It is easy to lay, cost-effective and well suited to domestic driveways.
• Asphalt: A denser mix with more fine material and bitumen, which gives a very smooth, tough and water-resistant surface. It is commonly used on roads and heavily used areas.

For most homes, a good-quality bitumen macadam laid in two layers is the practical choice. Where there is heavier use or a steep slope, a denser asphalt surface may be better. We recommend the right mix for your driveway at the survey.

1. 1

   Excavation: the old surface and soil are dug out to the right depth.

2. 2

   Sub-base: crushed stone is laid in layers and compacted to form a firm, stable base.

3. 3

   Edging: kerbs or edging blocks are set in concrete. They stop the edges of the tarmac crumbling and spreading.

4. 4

   Levels and drainage: the surface is laid to falls away from the house, with channel drains or gullies where needed.

5. 5

   Binder course: a thicker lower layer of tarmac is laid hot and rolled.

6. 6

   Surface course: a finer top layer is laid hot and rolled to a smooth, tight finish.

7. 7

   Finishing: the joints are sealed at the edges, and manhole covers are raised to the new level.

Laying in two layers, over a properly compacted sub-base and with firm edging, is what makes a tarmac driveway last. Many problems with tarmac come from skipping one of these steps.

• Black tarmac: The standard, clean finish.
• Red or coloured tarmac: Often used to mark borders, paths or parking bays.
• Contrasting edging: Block paving or brick borders frame the tarmac and give a neater look.
• Decorative chippings: A surface dressing of stone chippings gives a more natural, textured finish.

A well-laid tarmac driveway is long-lasting. How long it lasts depends mainly on the depth and compaction of the sub-base, laying two layers, firm edging, good drainage and basic care. Common causes of early failure are:

• a thin sub-base
• no edging, so the edges crumble
• standing water
• laying in cold or wet weather

Sometimes. Standard tarmac is impermeable. For houses in England, laying more than 5 square metres of impermeable surface in a front garden needs planning permission, unless rainwater is directed to a permeable area or soakaway within your property. We design the falls and drainage so the water stays on your land. Porous asphalt, which lets water through, is also available. A new dropped kerb always needs council approval, and the council or its approved contractor carries out the work on the pavement.

• In hot weather, new tarmac can be slightly soft for a while. Avoid turning the steering wheel while the car is stationary, and avoid parking in exactly the same spot every day at first.
• Avoid sharp point loads, such as caravan jacks or motorbike stands, unless you use a board to spread the load.
• Clean up fuel and oil spills quickly, because they soften bitumen.
• Keep weeds and moss off the edges, and sweep regularly.

Be wary of anyone who knocks on your door offering to tarmac your drive cheaply with "leftover" material from a nearby job. Rushed work with no proper sub-base, no edging and no written quote usually fails quickly. A reputable contractor will survey the driveway and give you a written quote, and you can take your time to decide. You can report doorstep traders through Citizens Advice, which passes reports to Trading Standards.