Granite countertop thickness

I hope this is the right forum to ask. I was wondering what is the appropriate thickness of a 3 cm countertop? We have one countertop that is only 7/8" thick where the other one is 1 1/8" thick, so you can clearly see a difference. The countertop company is trying to tell us that they are both 3 cm slabs but I don't understand how 7/8" thickness can still be considered 3 cm. Does anyone have any information about this? Everything I look up says 3 cm should be 1 1/4".

 

2.54 cm/inch so 3 cm is more than an inch, not less

 

Welcome to the forums.

I also don't understand what your contractor is saying and I do this all the time.

3cm granite = 1-3/16" thick. There is no plywood underlayment, it sits directly on the cabinets in most cases and does not have a lip. Overhang is usually 1.75" in front.

2cm granite, or 'regular' stone/quartz = 5/8" thick**.
2cm granite requires a 5/8" plywood underlayment. It usually has a 5/8" build up at the front to make it appear 1.25" thick and to hide the build up.

**Correction: 3/4" built up to appear 1.5" thick, some older granite was 5/8"

 

The countertops are installed in our newly built home. One side of the kitchen the granite is literally 7/8" thick and we are fighting with them that it needs to be replaced since 3 cm was ordered and this is way thinner than it needs to be. They are saying that the paperwork verified the slab was 3 cm and I think they are arguing that in the finishing process or something that it just ended up 7/8". I am trying to figure out if that should be acceptable or not because in my mind that is not acceptable but they are trying to tell me granite thickness can vary but I don't think that much variance should be acceptable. There is no plywood underlayment under any of the countertops.

 

Keep fighting, you've lost nearly a third of what you paid for on that end.

 

Thank you! I really think I am right on this and they are trying to pull one over on me. Does anyone have any guidelines or information I can bring to them about this? It seems pretty cut and dry to me... I am ok with the 1 1/8" but not the 7/8".

 

Every 3cm counter I work on is 1-3/16", usually with a full roundover bullnose at the front. It's also very expensive and you are paying for the look and the warranty.

The 7/8", which is probably .75, is not 3cm.

To be honest, most of my customers would be screaming into a phone right now