Most countertop quotes that go wrong go wrong before anyone measures anything. The homeowner is pricing a slab. The fabricator is pricing a job. Between the two sit a handful of decisions that move the number by hundreds or thousands of dollars, and they are easier to settle at the warehouse than at the install.
Here are the five, with the figures behind them.
1. Thickness: 2 cm or 3 cm
Quartz slabs come in two thicknesses. Two centimeter material is three quarters of an inch thick. Three centimeter material is an inch and a quarter. The difference sounds small and is not.
A 3 cm slab is strong enough to sit directly on the cabinets. A 2 cm slab is not: manufacturers specify a full three-quarter-inch plywood substrate beneath it on every horizontal run, which adds material and labor that the thinner slab was supposed to save. MSI puts the slab price difference at 20 to 30 percent in 2 cm’s favor, and then notes that once the substrate and the extra care in fabrication are counted, the installed difference is often much smaller than that.
Overhangs are where the thickness really shows. An unsupported overhang on 2 cm should not exceed 8 inches. On 3 cm it can safely reach 16 inches, though many fabricators stop at 12 without brackets. A breakfast bar with knees under it is a 3 cm job.
Weight follows thickness: roughly 9 to 10 pounds per square foot for 2 cm, 13.5 to 15 for 3 cm. And the elaborate edge profiles, waterfall ends and full ogees are standard on 3 cm and uncommon on 2 cm, because there is not enough material to shape.
The short version: 2 cm makes sense for vertical surfaces and for tops that will be laminated to a thicker edge. For a kitchen counter, 3 cm is the default for a reason.
2. The edge
The edge profile is a fabrication choice, not a slab choice, but it belongs on this list because it changes the quote and because the thickness decides what is possible. An eased or straight edge is the least expensive and the most current. A bevel or bullnose costs more machine time. A miter, which is what a waterfall end is, is the most demanding joint in the trade, and fabricators price it per miter, typically 150 to 500 dollars each depending on complexity and region.
Decide the edge before templating. Changing it after the slab is cut is not a small change.
3. Who fabricates, and how
We are a slab warehouse. We stock the material and help you pick the piece; a fabricator templates your kitchen, cuts and polishes the slab, and installs it. Keeping those two roles separate is deliberate, and it means the fabricator is your choice.
Two questions are worth asking any shop. The first is whether they cut wet. Quartz is 90 percent or more crystalline silica by weight, and cutting it dry releases respirable silica dust that causes silicosis, an incurable lung disease. The risk to fabrication workers has been serious enough that Australia banned the use, supply and manufacture of engineered stone outright from 1 July 2024. In the United States there is no ban, but OSHA’s silica standard limits worker exposure to 50 micrograms per cubic meter of air averaged over an eight-hour shift, and the agency runs a focused inspection program aimed at engineered stone fabrication shops. A shop that cuts wet, with water suppression on every tool and proper respiratory protection, is protecting its people and meeting the standard. That is also the kind of shop that will still be in business to honor its workmanship.
The second question is who is responsible for the seam. Ask to see photographs of seams the shop has done on the pattern you are considering. Every fabricator can cut a straight line. Not every fabricator can make a seam disappear in a veined Calacatta.
4. What the number covers
National figures for 2026 put installed quartz at 50 to 200 dollars per square foot, with a typical project running 1,500 to 8,000 dollars and a national average around 4,500 dollars. Material grades roughly break down as 50 to 60 dollars per square foot for builder grade, 60 to 80 for commercial grade, and 80 to 100 or more for premium patterns and larger formats. Installation labor alone is typically quoted at 10 to 30 dollars per square foot.
Those ranges are wide because the quotes they come from cover different things. Before you compare two numbers, make sure both include the same items:
- The slab itself, and how many. A veined pattern or a waterfall island often needs more than the square footage suggests.
- Templating, fabrication and installation.
- Sink and cooktop cutouts, which are priced each.
- The edge profile, and any miters.
- Seams, priced each.
- Plywood substrate, if the slab is 2 cm.
- Removal and disposal of the old countertop, and disconnecting and reconnecting plumbing, which many fabricators leave to a plumber.
A quote that names the slab by its individual number, lists the cutouts and seams, and states the thickness is a quote you can hold someone to.
5. The slab, by number
The last thing to settle is the first thing you will look at every morning: which slab. Not which color, which slab. Engineered quartz is consistent within a pattern, but a bundle still varies, and the piece that photographs well as a sample may carry a vein that crosses your sink cutout.
Choose the slab in person, in daylight if you can, with your cabinet door and floor sample beside it. Ask for the slab’s number and have it written on the quote. Then ask the fabricator to lay the template over a photograph of that slab before cutting, so you see where every vein lands. It is a ten-minute conversation that prevents the one countertop regret nobody can fix.
Sources
- MSI: How Thick Is Quartz Countertop? 2cm vs 3cm Specs (thickness, substrate, overhang, weight, price difference)
- Caesarstone: Plywood Under Quartz Countertops
- HomeAdvisor: How Much Do Quartz Countertops Cost in 2026? (cost ranges, updated June 2026)
- SlabWise: Planning Seams on a Large Island (seam and miter pricing)
- Wikipedia: Engineered stone (silica content, Australian ban)
- Safe Work Australia: Engineered stone ban
- OSHA: Silica, Crystalline (permissible exposure limit)
- AIHA: OSHA’s silica enforcement initiative targeting engineered stone
