How to Finish an Exposed Aggregate Sidewalk
- 1). Drag a straightedge across the freshly poured concrete surface in a sawing motion. This levels off the top and fills in any low areas.
- 2). Spray the entire surface with a retarder. Concrete retarders are designed to slow the setting process so the interior will harden first and the exterior will remain soft longer. Refer to the instructions on the retarder package to see how long the concrete should harden.
- 3). Push a soft-bristled scrub brush over the surface when it is hard enough to hold your weight without the aggregate moving. Spray the surface with a hose and brush off a thin top layer of concrete paste to reveal the decorative aggregate below.
- 4). Wash the surface with an acid wash and rinse with a hose to remove all solutions from the surface.
- 5). Cover the exposed aggregate with a damp breathable fabric and slow-dry the surface for about seven days, keeping the fabric moist.
- 6). Brush clear sealant over the exposed aggregate to protect it from weather, slow fading and to make the area easier to clean.
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