How to Cut L Shaped Quartz Countertop

Installing an L shaped quartz countertop can add style and functionality to your kitchen or bathroom. Quartz is an engineered stone that is very strong, scratch resistant, and low maintenance compared to other countertop materials. Cutting and installing an L shaped quartz countertop requires careful planning and the right tools, but it can be a do-it-yourself project if you have some DIY experience. Here is a step-by-step guide on how to cut and install an L shaped quartz countertop.

Planning and Measuring

The first step is to carefully measure and plan for your L shaped quartz countertop installation.

  • Measure the length and width of each section of the countertop. Remember that an L shaped countertop will have two separate slab pieces that you will cut and seam together.
  • Make sure to account for overhangs on the front and sides of the cabinets when taking measurements. The standard overhang is 1 1/4 inches.
  • Measure the locations of the sink, cooktop, and any other cutouts needed in the quartz.
  • Use painters tape to map out the measurements on the floor where the cabinets are installed. This will allow you to visualize the size and shape of the countertop.

Once you have all the measurements, use them to create a drawing of the countertop layout that you can use as a guide for cutting. Having an accurate layout is crucial for a successful install.

Buying the Quartz Slabs

  • Purchase two quartz slabs that are large enough to accommodate your L shaped design. Keep the vein and pattern consistency in mind when selecting slabs.
  • Have the supplier cut the slabs according to your measurements and layout. Be sure to communicate the locations of any cutouts.
  • If cutting the slabs yourself, buy them untrimmed. You’ll need to add extra length and width to allow for mistakes and trimming.

Cutting Quartz

Cutting quartz requires patience and the proper tools:

  • A circular saw with a diamond blade designed for cutting stone. A specialty quartz blade is ideal.
  • High-quality clamps to hold the slab securely while cutting.
  • A rotating cutting tool to cut inside corners and curves.
  • Safety gear – goggles, ear protection, gloves, and a mask. Quartz creates a lot of silica dust when cut.

Here are some tips for cutting quartz slabs:

  • Cut the quartz face down to avoid chipping. Use rigid foam under the slab to protect the surface.
  • Make multiple shallow passes when cutting to avoid overheating the stone.
  • Cut curves and inside corners with a rotating cutter at slow speed.
  • Cut holes for the sink or cooktop with a diamond hole saw. Go slowly to avoid cracking.
  • Always cut from the backside of the slab when making inside cuts like for a cooktop.

Seaming and Polishing

Once the quartz pieces are cut to size, you’ll need to seam them together to create the L shape.

  • Thoroughly clean and dry the edges to be seamed. Use denatured alcohol.
  • Apply seam adhesive to the edges. Use adhesive made for quartz like polyester resin.
  • Clamp the pieces together tightly. Allow the adhesive to fully cure per manufacturer instructions.
  • Carefully polish and smooth the seamed edges using a grinding pad and stone polishing pads.


With the L shaped pieces cut and seamed, you’re ready for installation:

  • Clean the cabinets and apply a bead of silicone caulk where the countertop will meet the cabinets.
  • Carefully lower the countertop pieces into place. Have helpers and use moving straps under each piece for support.
  • Apply caulk where the countertop meets the wall. Remove any excess caulk for a clean finish.
  • Allow the caulk to fully cure before using the countertop – usually 24-48 hours.
  • If desired, have the seamed edges sealed for extra protection and sheen. A quartz sealing product can be applied.

And that’s it! Proper planning, measurements, cutting, seaming, and installation will result in a stunning L shaped quartz countertop that will add functionality and style to your kitchen or bath for years to come.

Frequently Asked Questions

What tools do I need to cut an L shaped quartz countertop?

You’ll need a circular saw with a diamond blade made for cutting stone, high-quality clamps, a rotating tool for inside cuts, safety gear, and foam padding to protect the surface while cutting. Using the proper tools is essential.

What is the best way to make inside cuts in a quartz countertop?

Always cut from the backside of the slab when making inside cuts for things like a cooktop or sink. Use a rotating cutting tool at slow speed for clean inside cuts and curves. Cutting from the back prevents chipping on the visible top surface.

How do I get a seamless look when joining two quartz pieces?

Carefully seaming the edges together with adhesive made for stone will result in an almost seamless joint. Take time to thoroughly polish and smooth the seamed edges using grinding pads and polishing pads to blend the joint. A clear adhesive can help hide the seamed edge.

Should I have my quartz countertop professionally installed?

Quartz countertops can often be installed DIY if you are experienced with home improvement projects. Proper planning and measurements are key. For more complex designs or seamless looking seams, hiring a professional fabricator and installer may be worth the investment.

What are some tips for preventing cracks when cutting quartz?

Go slow with shallow passes when cutting, support the slab fully, cut face down, and use lots of water to keep the blade and stone cool. Rushing or forcing the saw blade can cause the quartz to crack or chip. Patience pays off.


Installing an L shaped quartz countertop adds beauty and function to any kitchen or bath. With careful planning and measurement, the right tools, and patience during cutting and seaming, DIY installation can be successful. Just take precautions when cutting quartz to prevent cracks and chips. Hiring a professional is recommended if you are unsure about managing all the nuances of cutting, seaming, and installing a quartz countertop. But with some skill and the tips above, an L shaped quartz countertop can be an attainable and rewarding DIY project.