4 Different Types of Flexible Water Supply Tubes and How to Choose One

Four different types of flexible water supply tubes

The Spruce / Kevin Norris

Flexible water supply tubes are flexible pipes that connect plumbing fixtures or appliances to your home's main water supply. These flexible pipes have largely replaced chrome-covered rigid copper or brass and come in a variety of materials, lengths, and diameters to fit any need, and are easily connected with simple wrenches or pliers. There is no pipe bending required, nor compression fittings that can be prone to leaking. Thus, just about any DIYer can successfully use flexible water supply tubes when installing a new toilet, faucet, or other plumbing fixture.

Flexible water supply tubing comes in four main types, with connections that are typically 1/4-, 3/8-, or 1/2-inch to match various water supply pipe and fixture tailpiece sizes. Before buying, it’s always a good idea to have a look under the sink or behind the fixture to see what length of flex tube you will need and the size of the end fittings required. Often, there is even a tag on the old flex tube that indicates the length and size of each end nut so you don’t have to measure or guess.

Below we break down the four types of flexible water supply tubes and the factors you should consider when choosing which is best for your connection needs.

Types of Flexible Water Supply Tubing
 Type Characteristics  Pros Cons
 PVC Solid PVC plastic, sometimes reinforced with braided nylon  Least expensive Not for exposed areas
Braided nylon PVC core with solid nylon fiber outer sheathing   Affordably priced Not for exposed areas
Polymer-coated PVC core inside tough, flexible polymer plastic sheathing  Attractive appearance, very durable and flexible Somewhat expensive
Stainless steel braided PVC core protected by double-layer sheathing of polymer and stainless steel fibers Attractive appearance, available in long lengths, very durable Most expensive
  • 01 of 04

    PVC Flex Tubes

    PVC flexible water supply tube

    The Spruce / Kevin Norris

    Best for: Enclosed sink, tub, and shower faucets; toilets where tubing is shaded from direct sunlight.

    Strong and durable, PVC flex tubes are made of a PVC (polyvinyl chloride) outer core that is usually braided with nylon, and an inner core made of solid PVC. This type of flex tube is often the least expensive option. But although they are cheap, they are very flexible, offering amazing strength and ease of use.

    Keep in mind that PVC flex lines are not as corrosion-resistant when used in an exposed area—sunlight can weaken the material. They are suitable for hot and cold water and are a great, inexpensive option for faucet and toilet connections alike. These inexpensive PVC flex lines are not quite as durable and long-lasting as braided nylon or other types.

    Tip

    Even if the old supply tubes appear to be in good condition, it's a good idea to replace them whenever you are installing a new toilet, faucet, or other plumbing fixture.

  • 02 of 04

    Braided Nylon Flex Tubes

    Braided nylon flexible water supply tube

    The Spruce / Kevin Norris

    Best for: Enclosed sink, tub, and shower faucets; toilets where tubing is shaded from direct sunlight.

    Flexible water supply tubes made from braided nylon come with a reinforced braided outer layer and have a solid PVC inner core. They are usually white in color. This type of water supply tube is good for use with either hot or cold water supply lines. They can be used for most fixtures, including faucets, toilets, and more.

    Nylon flex tubes are very flexible, so they can be bought long and easily looped if necessary. They come in a variety of lengths, and the attachment nuts may even have winged levers that allow you to hand-tighten the nuts without the need for a wrench or pliers. 

    Tip

    Hot water is hard on plastic supply lines, so it's a good idea to periodically inspect nylon tubing supplying hot-water faucets. These are more likely to fail than cold-water supply tubes. 

  • 03 of 04

    Polymer-Coated Flex Tubes

    Polymer-coated flexible water supply tube

    The Spruce / Kevin Norris

    Best for: Any fixture, including appliances; suitable for exposed areas.

    Polymer-coated flex tubes also have a PVC inner core, but the outer material is made of polymer-coated fibers. These tubes look a lot like stainless steel braided lines, and, like the stainless steel lines, they resist corrosion very effectively. Also, like braided steel, they are a good option where a premium appearance is needed, such as the exposed locations under a toilet or pedestal sink.

    Unlike stainless steel tubing, however, polymer-coated tubes are very easy to bend and loop in situations where they are overly long, or when you need to make up for a big offset between connections. Another difference is that this type of flex tube is less expensive than braided steel. Like all the other flex lines, these are hot and cold water compatible, so they can be used for many applications.

  • 04 of 04

    Stainless Steel Braided Flex Tubes

    Stainless steel braided flexible water supply tube

    The Spruce / Kevin Norris

    Best for: Any fixture, including appliances; suitable for exposed areas.

    Stainless steel flex tubes are made of braided stainless steel surrounding an inner tube of PVC or nylon. The finish is a shiny metal with a textured, fabric-like look. The stainless steel on the outside is great in exposed areas, not only for appearance but also because the stainless steel protects the tubing from the environment by resisting corrosion.

    This type of supply tube is flexible but not quite as flexible as braided nylon, PVC, or polymer-coated tubes. Stainless steel braided flex tubes are appropriate for both hot and cold water lines. Braided stainless steel is usually the most expensive option for flexible supply tubes, but is also the most attractive and most durable. They also come in longer lengths that can be used for connecting dishwashers, refrigerator icemakers, and similar appliances, where you need a water supply tube with exceptional longevity.

Choosing a Flexible Water Supply Tube

Flexible water supply tubing comes in four main types for connecting water supply pipes to various plumbing fixtures and appliances. All do the same job, but some, like PVC or braided nylon flex tubes should be limited to hidden areas that are protected from sunlight. If you need a tube that can withstand exposure to sunlight but also require maximum flexibility, opt for a polymer coated flex tube. Durability and length availability are other factors in making your choice. If you're connecting an appliance, such as a dishwasher or refrigerator ice-maker, stainless steel flex tubes are your best bet.

Consider the various performance characteristics of the four options before choosing the ideal type for your situation.