The Detail
Everything you'd ask a specialist on the doorstep.
Materials, methods, variations, and the small decisions that separate a 20-year driveway from a five-year one.
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The two-layer system
A proper tarmac driveway is laid in two distinct layers. The binder course (sometimes called the base course) is 65mm of 20mm aggregate hot-mixed with bitumen, the structural body of the driveway. The wearing course is 25mm of 6mm aggregate hot-laid on top, the smooth, fine-textured surface you actually see. Operators who skip the binder course and lay only a thin wearing course are saving themselves a day and you a decade of life.
Hot-laid versus cold-laid
Tarmac must be laid hot, typically delivered at 150°C and worked above 100°C, so the bitumen flows around the aggregate and bonds chemically as it cools. Cold-laid material is essentially gravel coated in cold pour, sold in bags for pothole repair. Any 'driveway' offered using cold-laid product is repair material being mis-sold as paving.
Block paved edging is structural
The block paved kerb around the perimeter of a tarmac drive isn't just decorative, it's the structural edge restraint that stops the tarmac crumbling under vehicle load. The blocks are concrete-haunched into a wet bed and laid before the tarmac goes down, then the tarmac is laid tight against them.
Drainage, falls and SuDS
Tarmac is impermeable, so falls and drainage must be designed in. We set falls at 1:60 minimum to a linear drain, soakaway or permeable strip. Where SuDS compliance is required (front gardens over 5m² draining to the road), we either install a permeable strip at the perimeter or specify a permeable tarmac wearing course.
Overlay versus full replacement
If your existing tarmac is structurally sound, no significant cracks, no movement, decent falls, a 25mm wearing-course overlay can give it another 10–15 years of life at a fraction of the replacement cost. If the existing base is failing, an overlay is throwing money away. We'll tell you straight which one your driveway needs.