Creating your own concrete garden bench is a rewarding project that adds durable, custom charm to your outdoor space. Don't worry if you're new to working with concrete; with careful planning, it's entirely achievable. Here's your essential guide.
First, design your bench. Sketch the dimensions. A typical seat height is 18 inches, with a depth of 15-18 inches. You'll build a wooden mold (formwork) from melamine-coated board or smooth plywood, as concrete picks up every texture. Ensure all joints are sealed tightly with silicone caulk to prevent leaks.
Gather your materials: high-strength concrete mix (fiber-reinforced is ideal), reinforcement (rebar or wire mesh), wood for the mold, release agent (cooking spray or commercial release), mixing tools, a trowel, and safety gear (gloves, mask, goggles).
Build your mold. Construct a sturdy box for the seat and separate side panels for the legs or pedestals, depending on your design. Apply a release agent to all interior surfaces. For a smoother finish, you can line the mold with thin plastic sheeting.
Mix the concrete according to the package instructions, aiming for a thick, oatmeal-like consistency. Pour it into the mold in layers, tamping down each layer to remove air bubbles. Place your reinforcement in the center of the pour. Use a screed board to level the top surface.
Curing is critical. Cover the concrete with plastic to retain moisture and let it cure in the mold for at least 48 hours. Then, carefully dismantle the mold. Keep the bench damp by misting it with water for at least a week, allowing it to gain strength slowly.
Once fully cured (after about a week), you can finish it. Sand any rough edges with a masonry sanding block. You can leave it as a raw, industrial gray, apply a concrete stain, or seal it with a penetrating sealer to protect against weather.
Finally, place your bench on a level surface in your garden. Its significant weight means it will stay put through wind and rain, providing a permanent spot for relaxation. Enjoy the satisfaction of creating a functional piece of art that will last for decades.