Asphalt and tarmac are not the same thing. Traditional tarmac, short for tarmacadam, uses tar as a binder to hold crushed stone together. Asphalt uses bitumen—a byproduct of crude oil—to bind aggregate. Though tarmac was once a go-to for roads, asphalt has become the modern standard. And these days, most surfaces referred to as “tarmac” are actually asphalt. So, while the names may overlap, the key distinction lies in the binder—tar for tarmac and bitumen for asphalt.

An asphalt driveway should be at least 3 inches thick over a compacted gravel base. Areas with poor drainage should have a thicker stone base. To install a new asphalt driveway over an existing driveway, the new asphalt should be at least 2 inches thick and the existing driveway should be in relatively good condition.

A driveway's lifespan varies by material. Asphalt driveways typically last 15 to 30 years, while concrete driveways last longer, between 20 and 50 years. The longevity of any driveway is affected by factors like extreme temperatures, heavy traffic, and the quality of maintenance. Regular upkeep, such as filling cracks, resealing the surface, and ensuring proper drainage, can help extend its life. For gravel driveways, regrading to fill in uneven areas every year or two is recommended.

If you're designing a new patio in an area with poor drainage, permeable pavers made from porous materials may help prevent water issues. Most permeable pavers feature a gravel-only aggregate base instead of a concrete base to allow water to flow through instead of getting trapped. While beneficial in some cases, permeable pavers come with higher initial costs and greater load-bearing limitations compared to traditional pavers.