Two dark driveway surfaces can look similar while managing rainwater differently. Conventional dense asphalt generally sends water over the surface towards drainage. Porous asphalt is designed to let water pass into an appropriate construction below it. The distinction needs to appear in the specification, not remain an assumption.
Ask which system is proposed
The word “tarmac” is often used broadly in household discussions. Request the actual product and build-up. A dark, textured surface should not be assumed porous simply because small spaces are visible between aggregate at close range.
Loading and use still matter. The product and supporting construction need to suit the driveway, vehicles and site conditions. A porous wearing course cannot compensate for an unsuitable base or poorly assessed ground.
Follow the complete water route
Porous asphalt needs lower layers and a drainage arrangement designed to receive the water. The ground may infiltrate it, or the system may include storage and an appropriate outlet. A dense layer beneath the top changes the situation and needs deliberate consideration.
For conventional asphalt, surface falls and collection details remain important. Neither system should discharge water towards a vulnerable threshold or unsuitable boundary simply because it is the easiest direction.
Keep maintenance appropriate
Protect porous surfacing from unnecessary soil, sand and construction contamination. Use the supplier's care instructions rather than applying a treatment intended for a different asphalt product. Ask how performance should be assessed if persistent ponding develops.
Planning suitability depends on the complete proposal and property circumstances, not a general claim that all dark driveways behave the same way. Keep the specification and water route with the handover records.
Before choosing: Ask whether the surface is dense or porous, what supports it and where rainwater goes afterwards. Those three answers establish a meaningful comparison that colour and texture alone cannot provide.
Discuss your project
Considering a tarmac driveway around Bristol? Smart Paving can review the intended use, supporting construction, edges and drainage before proposing a finish. Arrange a site visit.
Explore our tarmac service.
Related reading
- Standard and permeable block paving: the difference is below the surface too
- Why a resin bound surface can still need drainage channels
- New tarmac driveway care: steering, spills and the first uses
