Get matched with top paving pros in Heflin, AL

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 ideal driveway gradient is between 2% and 5%. Anything lower than 1% or higher than 15% can cause problems for your car or property. A driveway with less than a 1% slope increases your likelihood of flooding and water damage, while a driveway with a 15% grade or higher can be too steep for safe traveling.

Professional installers often include a deep layer of crushed gravel under permeable pavers to allow more runoff to soak through into the soil below. Many installations will include multiple layers of gravel, with coarser aggregate at the base and finer aggregate that sits on top of that bottom layer. Above the gravel, you’ll often find coarse sand that helps reduce paver shifting over time. Some permeable paver designs include a water collection system set into the gravel layer to route runoff to a safe area for disposal.

You’ll first need to install a base underneath your pavers for extra stability and drainage. Otherwise, the pavers can sink into the ground, and you’ll have to reinstall them. Use a base gravel layer of 4 to 6 inches for walkways and 10 to 12 inches for driveways. Compact your gravel layer every 2 to 4 inches so it’s nice and solid. After you install your gravel base, apply a 1-inch layer of sand on top.