Compression Fittings and Friction Washers: Understanding Plumbing Connections

Sinks, dishwashers, and toilets are just a few of the common items in a home that are attached through mechanical means. Fittings vary depending on the age of your home and the local building codes. In order to know how to take apart and properly repair any fixture, it is important to know what type of fittings are being used. Here are some of the most common varieties.

Older homes that were built prior to 1960 probably use friction washers to join the pipes. These cone shaped rubber washers were popular with plumbers who used a friction nut with a cone washer to join a smaller and larger pipe together. They would use the friction nut to force the cone shaped washer between the two sections of pipe to make a watertight seal.

Although contemporary plumbers seldom use this joining method, you can find replacement nuts and washers at your local hardware store. However, you might consider replacing these friction washers with one of the other connection types that have come into favor in the past fifty years.

Compression fittings are the most popular replacement for friction washers. Compression fittings have a brass body with a tapered seat, a compression ring, and a compression nut. To use this type of connection, you slide the compression nut onto the supply tube and they attach the compression ring. When the nut is tightened, the compression ring forms a seal around the supply tube.

Compression fittings are easy to use and can be repositioned several times as needed. They are made to standard sizes that fit the common rigid copper pipe as well as steel pipe.

Compression fittings include both adapters and shutoffs (or stops). Although there are some rules of thumb to follow to decide what type of compression fitting to install, you should be aware that many local building codes will require a shutoff, not an adapter, for most applications. This is particularly handy if you have to make minor plumbing repairs; instead of shutting off the water supply to the entire house, you can just use the shutoff under that fixture.

Fittings are often a common source of leaks in residential plumbing. If fittings are causing a leak in your home, consider repairing it yourself. Compression fittings perfect for the home improvement enthusiast; they are incredibly easy to use. However, you should have some basic knowledge of plumbing before beginning any work with fittings.

Faucets, appliances, and other fixtures all require some type of connection, so it is important to know which type is appropriate for your particular house. If you are replacing fittings, consider adding a compression shutoff to add greater ease for any additional plumbing repair projects. Of course, if you have very little plumbing knowledge, you may want to call a licensed plumber to install the fittings for you.