Compression fittings on a plastic pipe are known as the coupling of two pipes, a fixture, or a valve. You can use different types of plastic for a compression fitting. Plastic offers better flexibility and corrosion resistance and works effectively with a compression fitting. If you adopt a DIY approach, remember to support the pipework using the correct technique, helping reduce pipework failure. However, if you are unsure of plastic pipe compression fitting, consulting with the best plumbers in Modesto can guide you. Professional plumbers know which type of pipework works best for your plumbing system.

    What are Compression Fittings?

    Plumbers use compression-fitting couplings to join tubes or smaller flow-diameter pipes. Pipe material may vary according to your home plumbing system. The plumber may use brass, copper, or stainless steel to join PVC, nylon, plastic, or copper tubing. The market offers multiple design and size options for these versatile adapter fittings for multiple plumbing projects across different avenues, such as domestic, commercial, and industrial applications.

    Compression fittings secure a sleeve or ferrule over a joint to prevent leakage. Compression-fitting plastic tubing is solid and reliable and can be done using a pair of wrenches. Interestingly, these fixtures work well with damp pipes and don’t need heating.

    Parts of a Compression Fitting

    The pipe compression fittings comprise three parts:
    • Compression nut
    • Compression ring or inner ring or olive
    • Compression seat

    Steps to Use Compression Fittings

    1. Cut and Bevel the Pipe

    Install the compression fitting by cutting the plastic pipe. You can use a tubing cutter to make a clean, square cut. Next, bevel the pipe edges with a file. Alternatively, use a hacksaw to cut. If you use a hacksaw, be meticulous in your edge preparation.

    2. Put the Pipe into the Fitting

    Pipe lubrication with dishwashing liquid works well. The compression fitting’s nut should be loosened before you slip it onto the pipe, and ensure that the pipe end is encased. Use a lock ring inside the fitting for a tight pipe grip.

    3. Secure the Fitting

    Tighten the compression nut by hand. You will not need a wrench to seal it. You may notice a little water collecting around the edge of a plastic compression fitting which is normal as such leaks stop in a day or two. If the fitting sprays water, you may need adjustable pliers for tightening.


    Compression fitting creates a tight seal by applying a compressive force to the pipe. A plastic compression ring should be used instead of a metal ring to join plastic pipes with compression fittings. You must ensure that the fittings you choose for your project match your plumbing pipe system. Consulting with an expert plumber can help you make an informed choice.