Plywood Subtop For Granite Countertop

I love some of the quartz options that mimick carrera marble but the granite dealer is insisting that i need a 5 8 plywood over the cabinets for support.

Plywood subtop for granite countertop.

The result is a stable but open support structure that dissipates excess heat far better than a solid subtop. Remove the granite slabs that were dry fitted only. You can use it as a stand alone product as well as a finish type plywood if it has a laminate finish that you can paint or finish according to personal preference. This provides adequate support for a wide range of finish materials.

Now this assumes a full depth granite 3 cm or 1 1 4 thick is used. Face frame cabinets that are a little higher may require just one layer of 1 2 plywood strips but the principle is the same. If a thinner granite is being used 2 cm or 3 4 a plywood subtop will need to be installed. Set granite in place for the sink counter and trace the exact line around the opening for the sink onto the plywood subcounter.

I just had white shaker cabinets installed and am now selecting a countertop. The marble institute of america guidelines suggest an unsupported overhang for 2mm of 4 max and 8 for 3mm. With this scenario plywood is cut to fit the countertop layout and screwed to the cabinets prior to the stone tops being installed. Drop in the sink.

Use a spade bit to make a pilot hole in the plywood and use a jigsaw to cut the sink hole. If using plywood merely as a framework for the finish work surface to be adhered to inch thick plywood is recommended for strength. Finish countertop height ends up at the industry standard of 36. For weight calculations 2mm weighs about 13 lbs per square foot and 19 lbs sf for 3mm.

Make it about 1 8 larger than the line you drew. For 13 16 2mm tops the subtop should be a minimum of 5 8 plywood no mdf or particleboard.