When installing granite countertops, you will not need an underlayment of plywood if the granite has a thickness of 3 centimeters (about 1 1/4 inches). However, 2 centimeter granite needs support under it since it is less sturdy, so having a plywood underlayment is a must.
Well, however, for granite with a thickness of 2 centimeters (about 3/4 inches), you will definitely need to use plywood for support. Just like any heavy stone, granite can crack if not protected properly. 3 centimeter granite is much sturdier than 2 centimeter granite and will not break or get damaged when installed without plywood.
There is no plywood under the granite. From contributor K: You need to have a subtop to glue the granite to. This will prevent it from cracking when there are larger unsupported areas. Hereof, How do you support a dishwasher with a granite countertop?
Will plywood stop granite from bending?
The answer to this seems pretty clear when you consider one thing: It takes a substantial amount of force to bend granite, but it only needs to move a few micrometers* to break. Now you just ask yourself whether a layer of plywood will prevent that miniscule movement. No, it won’t. Physics has no interest in the opinion of the masses.
What is the best underlayment for granite countertops?
Plywood does a great job of balancing out the granite and keeping it level and flush with your backsplash and cabinets. A plywood underlayment also provides better support for your granite countertops than most other materials.
However, 2 centimeter granite needs support under it since it is less sturdy, so having a plywood underlayment is a must.
What grade of plywood is used for countertops?
Plywood is an engineered wood that comes in various grades ranging from A through D. Grade A is the best quality and most expensive while Grade D is the worst quality and least expensive. Almost everyone installing 2cm granite countertops should use Grade A plywood.
While I was researching we ran into the inquiry “How much plywood to put on top of cabinets for slab?”.
Finished installing cabinets for my kitchen and getting ready to call a vendor to take measurements for granite slab. In general, should I be putting in 5/8″ or 3/4″ plywood on top of these cabinets to receive slab. I also plan on setting a stainless steel undermount sink.