How To Cut Composite Decking: All The Basics

The good news is that cutting composite decking is very similar to cutting wooden decking, so the steps involved are pretty much the same. There is one caveat – and that is that composite boards don’t have any attractive end grain to leave exposed as you can with wooden boards. That can mean that the way you cut some of them is different. You will often see composite decking done with ‘picture frame’ boards around the perimeter that require 45-degree miter cuts in order to achieve that more aesthetically pleasing look.

So it is important to be prepared and know how to use the right tools for the different tasks involved, be it straight cuts or 45-degree miter cuts.

It also goes without saying that having the correct safety gear while using electric saws is super important, so as with anything DIY that you don’t do every day as a professional, preparation is key.

Professionals cut building materials with rather dangerous sharp spinning things every day of the week, but if you are a DIY person, please take it slow and carefully until you are very familiar with the process and techniques.

Don’t Forget Safety First When Cutting With Saws

When cutting with saws, always remember to put safety first. Make sure you are wearing the proper safety gear, such as gloves, goggles, ear protection, and a dust mask. Also, be sure to keep your fingers away from the blade and never force the saw through the material you are cutting. Another aspect is the sharpness of the blade. The sharper the better because it will cut faster, result in smoother cuts, and will be less likely to grab.

Making sure the saw is in good condition and you know exactly how to use it correctly is vitally important.

Ensure that you let the saw do the work and make sure not to force the blade into the material as this could cause damage to the blade or make the material caught in the blade.

Types Of Saws For Cutting Composite Decking

There is nothing special about the types of saws used to cut through composite decking compared to other materials such as wood, but there are some options when it comes to the type of saw blade for different purposes and the number of teeth they have. It all comes down to managing the harder outer shell of the decking that can tend to splinter if you don’t proceed carefully. You will find that you can purchase a specific saw blade for cutting composite decking that will have fewer teeth than usual. The lower number of teeth on a blade to cut composite or even hard-shelled wooden decking can assist in stopping the material from splintering during the cut. While this is true, the best way to ensure a clean-cut, no matter how many teeth are on the blade, is to proceed slowly and smoothly – pro tip for you right there.

So there are three main types of saws you may need to use while doing a composite decking project:

  • Miter Saw (chop saw): Use this type of saw to square-cut the boards to length or to do 45-degree angle cuts for picture frames around the edge of the square-cut pieces.
  • Circular Saw: Use this to cut boards to a specified length once they are clamped or attached. Use a chalk line to mark where to cut across multiple boards. If you only have one saw, a handheld circular saw is the one to have because at a push, it can do all the cutting you need. The only downside to a circular saw is that all the cuts will be hand guided. This will mean you need to take extra care to keep everything straight and square. You do need some practiced hand-eye coordination skills with using a circular saw so you won’t have accidents or even poor cutting results. Clamping down decking material before cutting an overhang is helpful, especially while still developing the skills.
  • Table Saw: While not absolutely required, a portable table saw is nice to have for some specific decking tasks such as ripping jobs. Make sure you have your head around anti-kickback carbide tipped blades for safety and know how to set the height of your blade slightly above the height of your board to reduce the chance of kickback.
  • Give jig saws a miss in this area. They are not suitable for cutting composite material, although they are capable of cutting the material in a pinch. Circular saws and miter saws are the go if you want to cut composite decking successfully.

Remember To Cut On The Waste Side Of The Line

Before you start cutting with a saw, you need to know how to mark and cut. With a pencil or chalk using a quick square edge, mark the board with the line across where you want to cut it after measuring the length you want with a tape measure. To make accurate cuts, it is important to remember to cut on the waste side of the line. This will ensure that the cut is straight and accurate in length.

Tips For Cutting Composite Flooring

  • Clamping down the decking material before cutting with a circular saw is the best approach to get the best cut.
  • Table saws are another alternative. A circular blade is located beneath the workbench. The deck boards are simply pushed toward the blade with these tools. In terms of deck cutting, this is the most practical, safest, and versatile option.
  • Miter saws will result in the best crosscuts, but make sure you have enough support for longer pieces of the board when you place them in a position to cut.
  • Use a chalk line across multiple planks to mark where you want to use a handheld circular saw to trim the ends of the boards.
  • When cutting composite decking, you’ll need to make sure that your blades are sharp and dry. If the blades are dull, they will create a lot of noise as they stroke through the material. This is not only noisy for everyone but also causes unnecessary wear on your blades.
  • Drying your blade also ensures that there isn’t any moisture or dirt on the blade when it comes into contact with the material–this can lead to unwanted discoloration or staining on your decking surface.
  • Before cutting, make sure to remove any dirt or debris that may be on the surface of the decking. This will ensure that you are cutting cleanly and without damaging the composite fibers.

Maintaining Your New Composite Decking Installation

After installing composite decking, the fun part is the ease of ongoing maintenance. Taking care of your composite decking is just as important as installing it in the first place, but is very easy compared to different materials such as natural wood. Maintaining your deck is easy with a few simple steps. First, you should remove debris and loose dirt by cleaning off the deck with water and a garden hose. Next, scrub down the board with a detergent-based cleaner to remove any stains, dirt, or oil. Finally, rinse the surface completely and allow it to dry before using your new composite decking again. Easy!


Q: Can you cut composite decking?

Yes, you can cut composite decking just like wood, with no special tools required. Some of the best tools for cutting composite decking include circular saws, miter saws, and table saws. It is recommended to use a carbide-tipped saw blade with a tooth count appropriate for your saw type to ensure a smooth, clean cut[1]. You can also use a jigsaw for curved cuts[1]. When cutting composite decking, it’s essential to consider factors like thermal expansion and to cut the boards when they are cool to achieve a more accurate cut[8].


Q: What is the best blade for cutting composite decking and do you need a special saw blade to cut composite decking?

Some of the best blade options for cutting composite decking include:

  • Carbide-tipped circular saw blades with 40-60 teeth – These provide a smooth, clean cut on composite materials. Many experts recommend 40-tooth alternate top bevel blades specifically for composites (Source[2]).
  • Specialty blades like the Diablo TrexBlade or Freud Diablo decking blades – These are designed for cutting Trex and other composite decking brands. They have a high tooth count and modified grind to optimize cutting performance (Sources[3], [6], [8]).
  • Thin jigsaw blades – For curved cuts, thin and flexible jigsaw blades work well to handle the composition of materials like Trex (Source[1]).
  • Lower-tooth count (24-40 teeth) table saw blades – Allow for faster feed rates needed on table saws while still providing a clean cut (Source[1]).
  • Higher quality blades – Carbide tipped blades from reputable brands like Diablo, Freud, DeWalt, Bosch, etc. tend to stay sharper longer when cutting composites (Source[2]).

The most important factors are using a blade with a tooth count appropriate for your saw type, a sharp carbide tip designed for composites, and making sure to feed the material at the proper rate. This will provide smooth, splinter-free cuts.



To do a proper job of a decking project, you are going to need to do a bunch of cutting of different types – no way out of it. Once you master the process and techniques required for cutting composite decking, you will have the skills in place for other cutting jobs like regular wood decking, fencing, lumber, or whatever else comes along.

Other Composite Decking Blog Posts On

Check out our post on fixing composite deck cracks and how to deal with composite deck warping.

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