Pouring an Aggregate Border Around a Concrete Driveway
It is easy to add a decorative, non-slip edge to your concrete driveway with an aggregate border. It is easy to include this border at the time you lay your driveway by creating an extra form around the area for the plain concrete. Select aggregates that are colored and sized to suit your home exterior. Follow these guidelines to pour an aggregate border for your concrete driveway.
Step 1: Construct the Forms for the Aggregate
Place the forms for the aggregate at the same time as you build the forms for the main driveway sections. They should be no more than 18 inches wide, so that the aggregate will compose 3 feet of your driveway's total width. Drive stakes into the ground with just 4 inches showing above the driveway trench top, 20 inches outside the main forms. Tie rope to the top of each stake for leveling measurements.
Lay 2x4 planks into the trench and nail them to the stakes with double head nails, ensuring they are level with the stake tops. Coat the inside face of the planks with motor oil for easy removal. Order the cubic footage of aggregate you need, specifying color and size. Some aggregates use small, fairly uniform pea gravel, while others can be made with larger, multicolored river rock pebbles.
Step 2: Pour the Main Driveway
Pour the concrete for the main driveway body and remove the forms for those sections once the concrete has hardened. Now you are ready to pour the aggregate.
Step 3: Mix and Pour the Aggregate
Pour the aggregate across the top of the driveway and then down one side of the driveway at a time, beginning with the section closest to the house. Pour the far side of the driveway as soon as the near side is poured. Have helpers to do leveling and floating of each section while the next is being poured.
Step 4: Level and Float the Aggregate
Use a plank 18 inches long to level or screed the aggregate. Make sure it comes into direct contact with the cured concrete of the main driveway sections, leaving no gaps. Use firm pressure on the bull float to pop out any air bubbles in the monolithic aggregate and allow it to set for 5 to 10 days. It will take a bit longer to harden than plain concrete because of its density and texture. Use the grooving tool to cut in control joints every 10 feet down the borders.
Step 5: Keep the Aggregate Damp as It Hardens
For the first 5 days after pouring, mist the aggregate with the garden hose and cover it with damp burlap mats. Dampen these mats every morning and pin them down with rocks or bricks.
Aggregates are easy to maintain, hide grit and leaf mold, and provide a high-contrast textured border to a solid concrete driveway.