Which Saw to Drill Quartz Countertops

Quartz countertops are a popular choice for kitchen and bathroom remodeling projects due to their durability, low maintenance, and stylish appearance. However, these countertops are made from an engineered stone material that can be challenging to cut and drill holes into. Selecting the right saw is crucial to avoid cracking or chipping the quartz. This article will provide an in-depth look at the best saws to drill holes in quartz countertops without damaging the material.

Diamond Hole Saws Are the Best for Drilling Quartz

Diamond hole saws, also known as diamond core drill bits, are specially designed for drilling into hard materials like quartz, granite, porcelain, and ceramic tile. The outer perimeter of the bit contains industrial-grade diamond abrasives that grind away the quartz leaving a clean, crisp hole. Diamond bits come in various sizes to drill different diameter holes. They can drill holes from 5mm to over 3 inches in diameter.

Compared to standard twist drill bits, diamond hole saws have the following advantages when drilling quartz:

  • Diamond abrasives cut cleaner holes in quartz avoiding cracks and chips
  • Cooling holes in the bit dissipate heat preventing the quartz from scorching
  • Center drill point keeps the bit stable and prevents “walking”
  • Can drill hundreds of holes without dulling like twist bits
  • Create smooth hole edges without requiring additional finishing

We recommend using diamond hole saws for any size hole you need to drill in a quartz countertop. They are well worth the investment over standard drill bits that often damage and crack quartz.

Select the Proper Size Diamond Bit

Diamond hole saws come in different sizes specified by the diameter of the hole they drill. Choose a bit diameter around 1/8” larger than your desired hole size to allow a little room for error. Here are some common sizes and applications:

  • 5/8 inch – Electrical cords, sink drains, medium faucets
  • 1 inch – Faucet holes, soap dispensers
  • 1 1/4 inch – Larger faucets, handles, spouts
  • 1 1/2 inch – High spout faucets, instant hot taps
  • 2 to 3 inch – Kitchen sinks, bar sinks

Having a range of sizes on hand allows you to tackle various drilling needs for your quartz countertops. Start with smaller pilot holes before using large diameter bits to prevent cracking.

Brands of Diamond Hole Saws for Quartz

Look for diamond bits made specifically for stone and ceramic materials. Here are some reputable brands to consider:

  • Dewalt – Their diamond hole saws last long and cut smooth holes. A top choice for quartz fabricators.
  • Milwaukee – Durable brazed diamond cutting edges withstand heat and impacts.
  • Bosch – Laser-cut, industrial-grade diamonds stay sharp hole after hole.
  • Lackmond – Quality diamond bits specially designed for quartz and granite.

Stick with name brands over cheap generic diamond bits that lose their diamonds and cut poorly in quartz. High-quality diamond hole saws are worth the extra cost for smooth drilling results.

How to Drill Holes in Quartz Countertops

Drilling clean holes in quartz requires taking precautions to prevent cracking and chipping the material. Follow these steps for best results:

1. Mark the Hole Location

Use a pencil or marker to mark the center of where you want the hole. If drilling for a sink or faucet, set them in place and mark around them. This ensures you drill in the right spot.

2. Start with a Pilot Hole

Begin drilling a smaller 1/8” pilot hole on your mark before using a large bit. The pilot hole gives the diamond bit stability and prevents walking across the surface.

3. Run Water Over the Bit

Have a spray bottle filled with water on hand. The water keeps the diamond bit cool preventing heat buildup which can crack the quartz.

4. Drill at Low Speeds

Diamond bits work best from 900 to 1,500 RPM. Higher speeds can overheat and fracture the stone. Set your drill to low gear if possible.

5. Apply Light Pressure

Allow the diamond abrasives do the cutting, applying only light pressure. Too much force can bind up and crack the quartz.

6. Frequently Back Bit Out

Every 20 to 30 seconds, back the bit out to clear swarf that builds up. This prevents binding and overheating.

7. Check Hole for Chips

Carefully inspect the hole for any small chips around the top edge. Use a file to smooth down any minor flaws if present.

By taking these precautions, you can cleanly drill holes in your quartz countertop and have them ready for sink and faucet installation.

Troubleshooting Drilling Problems in Quartz

Drilling holes in quartz does not always go smoothly, even when using diamond hole saws. Here are some common problems and solutions.

Bit Walking Across the Surface

If the bit wanders away from your pilot hole mark, it means you likely did not create a proper starter hole for the bit to sit in. Solid carbide center spurs help, but try drilling a larger pilot first if the bit walks.

Quartz Chipping Around Hole

This usually happens from feeding too much pressure or drilling too fast overheating the quartz. Allow the diamond segments to cut at lower RPMs and ease off the pressure. Chipping can also occur if you do not back the bit out periodically to clear debris.

Uneven Hole Edges

Uneven holes with ridges mean the diamond segments on your bit are worn down. Dull bits require more force to cut resulting in ragged holes. Replace the bit for clean smooth cuts.

Bit Overheating

Diamond bits conduct heat into the stone they are cutting. Use water to cool the bit and take frequent breaks to allow cooling. Slow your drilling speed as well. If the bit overheats it can leave scorch marks around the hole.

Cracking Around the Hole

Large cracks radiating out from the hole mean too much lateral force was applied. Let the diamonds do the cutting using less hand pressure. Cracking can also occur from heating if the bit binds up in the hole.

Stay alert to any signs of trouble and adjust your technique to prevent problems. With care, diamond hole saws will provide quality holes in quartz.

Steps for a Clean Sink or Faucet Installation

Once your holes are drilled, follow these tips for a seamless sink or faucet installation:

  • Clean around holes with denatured alcohol to remove oily residue
  • Apply clear silicone caulk around the top side of holes
  • For undermount sinks set sink in place, insert threaded rods through faucet holes to support sink weight
  • When securing faucets or other fittings, avoid over-tightening nuts and bolts
  • Allow caulk to fully cure for 24 hours before using sink
  • Use foam backer rod to fill gaps below sink rim
  • Run water and check for leaks around sink and faucets

Taking the time to properly prepare the holes and allowing caulk to fully set delivers a flawless finished installation.

Maintaining Your Diamond Hole Saws

With proper care, your diamond hole saws will drill hundreds of holes in quartz. Here are some tips for maximizing their lifespan:

  • Rinse bits under water after each use to remove debris
  • Store bits individually to prevent diamond segments from contacting each other
  • Inspect segments periodically, replace when excessively worn
  • Consider bit sharpening service after heavy use
  • Lubricate threads with machine oil to prevent rusting

Rotate your diamond bit selections to evenly distribute wear. With basic maintenance, diamond hole saws will provide years of smooth cutting performance in quartz.

FAQs About Drilling Quartz Countertops

Can I use a regular drill bit in quartz?

It is not recommended as standard twist drill bits lack the diamond abrasives and cooling features to cut quartz cleanly. They often crack and chip the stone. Invest in proper diamond hole saws for smooth drilling results.

How fast can I drill holes in quartz?

Keep your drill speed between 900 to 1,500 RPM when drilling quartz. Any faster risks overheating and damaging the stone. Let the diamond segments do the work using light pressure.

Do I need to polish the holes after drilling quartz?

With a quality diamond bit, your holes should come out smooth with little need for polishing. You can wrap a piece of sandpaper around a dowel rod to polish the inside walls if desired.

What size pilot hole should I drill before using a large diamond bit?

Drill a pilot hole around 1/8” to 1/4″” in diameter before using a larger 1” or greater sized diamond bit. The pilot hole provides stability so the bigger bit does not wander.

How can I tell when to replace my diamond hole saw?

Inspect the segments around the perimeter of the bit. If the diamonds appear heavily worn or rounded over replace the bit to maintain clean cutting ability. If drilling requires extra force, the bit is likely dull.

Drilling your own holes allows you to add fixtures anywhere in your quartz countertop. With the proper diamond hole saw and careful technique, you can install sinks and faucets with seamless results. Just take it slow and let the diamonds do the hard work. Soon you will have glistening new sinks and faucets mounted in your beautiful quartz countertop.


Drilling clean holes in quartz countertops for new sinks and faucets takes the right tools and techniques. Diamond hole saw bits are engineered to cut precise holes in stone materials like quartz without cracking or chipping. Their diamond segments grind away the quartz leaving smooth edges. Starting with a small pilot hole and drilling at low speeds while lubricating with water allows these specialized bits to work their magic. With quality diamond hole saws on hand like Milwaukee, DeWalt, Bosch, and Lackmond models, you can drill perfect holes to install new fixtures in your quartz countertops. Taking precautions like starting with a pilot hole, running water over the bit, and easing off pressure yields professional results. Investing in the proper diamond bits saves time and avoids damage drilling quartz yourself. Follow these best practices for hole saw usage and care to maintain their cutting performance. Soon you will have elegant new sinks and faucets mounted seamlessly within your beautiful quartz countertop.