Plywood Subtop For Granite Countertop

Use a spade bit to make a pilot hole in the plywood and use a jigsaw to cut the sink hole.

Plywood subtop for granite countertop.

Strips of the same type of plywood cut to 4 inch widths should be glued or screwed to the edges of the countertop to strengthen this area making it twice as thick as the rest of the countertop. Make it about 1 8 larger than the line you drew. If a thinner granite is being used 2 cm or 3 4 a plywood subtop will need to be installed. This provides adequate support for a wide range of finish materials.

The marble institute of america guidelines suggest an unsupported overhang for 2mm of 4 max and 8 for 3mm. 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 using plywood merely as a framework for the finish work surface to be adhered to inch thick plywood is recommended for strength. Set granite in place for the sink counter and trace the exact line around the opening for the sink onto the plywood subcounter.

The result is a stable but open support structure that dissipates excess heat far better than a solid subtop. Drop in the sink. For weight calculations 2mm weighs about 13 lbs per square foot and 19 lbs sf for 3mm. 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.

Now this assumes a full depth granite 3 cm or 1 1 4 thick is used. With this scenario plywood is cut to fit the countertop layout and screwed to the cabinets prior to the stone tops being installed. I just had white shaker cabinets installed and am now selecting a countertop. 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.

Remove the granite slabs that were dry fitted only. Finish countertop height ends up at the industry standard of 36.