Flexible Water Supply Lines

Find Out How to Use Flexible Water Supply Lines

Plumber Working on Dishwasher
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Flexible water supply lines are very useful for connecting the water supply to a plumbing fixture. Do you know how and when to use flexible water supply lines?

Here are some common questions about flexible water supply lines:

What is the best type of flex line to use?

Most often this is a matter of opinion and preference. For common uses like connecting a water supply to a faucet or toilet most flexible water lines are going to be about even.

I do usually opt for stainless steel braided flex lines when I have a choice because to me they just seem the most durable option. When purchasing a flex line to meet extreme pressure requirements or for use with a special type of liquid the best thing to do would be to look at all of the specifications for each flex line material before making a decision. This is usually not the case for most household plumbing projects so it often comes down to picking one from the selection of flex line types at the local home improvement or hardware store. Note: One thing to keep in mind is that in some areas the plumbing and building codes may restrict the type of flex line material that can be used in home plumbing. Check building code restrictions before using something other that what is already in place.

When do water supply lines or flex lines need to be changed?

As a rule of thumb whenever you replace a fixture such as a faucet or a toilet the flex lines should also be replaced.

Even though a supply line may look like it is still in good shape you can save yourself a lot of trouble by replacing it. The reason for this is that when the rubber seal is disturbed it can be difficult to re-seal, especially if the rubber gasket is older. A rubber gasket that has been in place for several years is probably less flexible than when new and will not often form a watertight seal.

Many new kitchen faucets and even bathroom faucets are beginning to come with flex lines built into the faucet so you will be changing these for sure when replacing the faucet.

What kind of tools do I need to change a flex line?

A pair of pliers or crescent wrenches is all that is needed for installing water supply lines. The key is to have two pliers or wrenches, one to hold against the shut-off valve or faucet tubing and the other to tighten the nut on each end of the flex line. It is always a good idea to hold against fittings when tightening or removing so that you do not turn parts that you did not want to move. That could be the start of a bigger project if the torque causes a pipe or fitting to break.

What else can I use flex lines on?

I have mostly talked about flex lines for faucets and toilets but the same type of flexible water supply lines are made for ice makers and dishwashers. These are flex lines are also complete and they are just as easy to hook up to as any faucet or toilet water supply. Just have a good idea of what length you will need before purchasing. I have seen ice maker flex lines come in 5-foot, 10-foot, and even ​20-foot length. Dishwasher flex lines often come in 5-foot and 8-foot lengths.

One important thing to note is that flexible water supply lines need to be in an area that is serviceable so you do not want to use them in areas that you can’t easily access such as in a wall or under the house.