Concrete bench top - faux granite

This is the story or designing and building a self supporting kitchen sink with double tubs and a concrete top surface.

After spending considerable time scouring trademe for suitable second hand sinks I gave in and purchased exactly what I needed from the Oliveri range through our local (Kaikoura) Mitre 10. While it was excessively expensive (what isn't these days) I was happy with the quality.

Now that I had the sink it was time to construct a frame that would act as the mould into which concrete would be poured to form the bench top. Essentially this consisted of two low wooden rectangles, one inside the other. The smaller, shaped to create an opening into which the sinks would rest, had to have curved corners and additional strip of wood that, when removed, would create a lip that small clamps on the underside of the sink would grip onto.

The frame was placed on top of a layer of thick plastic and reinforcing steel laid in the areas where concrete would go. I used some building rods, some thick mesh and barbed wire. The finished thickness of the concrete 'slab' was 50mm.

The layer of plastic was intended to create a smooth surface on the bottom (which would become the top). Bolts protruding from the ends provide a way to connect the concrete to the wooden frame.

I made a wet mix in the hope of filling all the corners of the frame well and to get a nice smooth finish. For colour I mixed in a big helping of ebony black pigment. The pour went well, and the sloppy mix settled well as I jiggled things into place.

Weeks went by and I tried not to think of the next steps and allowed myself to be sidetracked with other projects. Eventually I couldn't postpone the inevitable any longer and attempted to design a wooden frame and cupboard system that would support the new concrete surface.

Like most things round here the design process was more of an evolution than a premeditated plan but things came together. Using some nice native timber salvaged from the roofing project on the guest house I was able to mill enough wood to build a sturdy frame. There was added challenge of constructing things upside down on top of the bench top and then flipping everything as one joined unit.

One the skeleton was complete and standing up the right way it was fairly easy to attach the sink and with the help of some volunteers, moved it into the house. Now it was a matter of attaching the drain pipe and creating the various cupboard doors.

While it was a long time coming we are very happy with our new situation.