How to Choose the Best Plumbing Fittings

Plumbing fittings play an important role in any plumbing system, adapting to many different shapes and sizes to connect lengths of pipe or tubing. But how do you know which is the right plumbing fitting for you? 

In this article, we will cover everything you need to know when choosing a plumbing fitting. Keep reading to learn more…

Understanding types of plumbing fittings

Plumbing fittings enable the configuration of plumbing layouts. By connecting lengths of piping, they uphold the integrity and efficiency of fluid transport systems, and allow them to be easily maintained or expanded.

There are several different types of plumbing fittings, each designed to serve different purposes in the system. Let’s look at some of the common types:

Couplings

Couplings are short pieces of pipe or tube that are used to connect together two pipes of matching diameter in a straight line. They feature either a socket, or female threads at one or both ends.

Sometimes referred to as “sleeves”, couplings are a simple, yet effective solution for connecting sections of pipe, and come in an array of different types, including compression couplings, slip couplings, and flexible couplings.

They are commonly used for repairing sections of pipe where a segment has been damaged, or extending the overall length of a pipeline by coupling pieces of pipe together.

Elbows

Elbow fittings allow pipes to change direction. The three most common angle variations are 27-degree, 45-degree, or 90-degree bends, which makes them ideal for navigating a pipe system around corners or through narrow, twisting areas.

A 90-degree elbow is often used in plumbing systems to change the direction of a water supply line, whereas the slight angle of a 45-degree elbow allows for a more gradual bend, reducing turbulence and noise.

Tees

Tee fittings consist of three openings shaped in the letter ‘T’. They combine or split the flow of a fluid, which is essential in branching pipe systems, such as splitting a main water line throughout different areas of a building, or connecting multiple waste pipes into one singular source.

Buy Now – Elbow and Tee Fittings

Culotte

With their ‘Y’ shape design, culotte fittings are similar to tee fittings in their application, by connecting or splitting branching pipe systems. Thanks to their design, they allow a more gradual split or join than tee fittings, which can be useful in narrow areas like behind sinks.

Reducers

Reducer pipe fittings connect pipes of different diameters, allowing for a smooth transition of fluid transfer without damaging the pipes.

Reducer fittings are useful when connecting to pre-existing pipes of different sizes, or when the flow has to be limited or expanded in a piping system.

Bungs

Bung fittings are used at the end of piping systems to block or prevent the flow. Sometimes referred to as a “stopper”, they are inserted into the pipe to act as a seal – either temporarily or permanently.

Unions

Unions are similar to couplings, but are designed to connect and disconnect pipes easily. This makes them ideal for pipelines that require frequent maintenance, or access for inspection, such as control valves, or water metres.

The main difference between a coupling and a union is their function. Couplings connect pipes to other pipes, whereas a union joins and disconnects components of a pipe system.

What materials are plumbing fittings made of?

The material used to create a plumbing fitting can have a big impact on its durability, compatibility, and application. Below, we’ve explored the common materials used…

Copper

Copper plumbing fittings are known for their durability and corrosion resistance. Because of this, they are widely used in water supply lines and heating systems, as they can withstand high temperatures and pressures. 

Copper has a long lifespan, and naturally resists bacterial growth, which makes it safe for use in water supply lines. They are also commonly used in fire suppression systems, and refrigeration systems, due to their durability and thermal properties.

Brass

Brass plumbing fittings are often used in potable water systems, because they offer excellent corrosion resistance, and are suitable for use in both hot and cold water systems. They are highly durable, and easier to shape and install compared to other fittings, which allows for a secure, reliable fit.

Brass fittings are commonly used in residential and commercial plumbing, natural gas lines and propane systems, as well as HVAC heating and cooling systems.

Buy Now – Couplers and Reducers

Stainless steel

Stainless steel plumbing fittings are often used in commercial and industrial applications, where durability is critical. This is because they offer a higher level of strength and corrosion resistance. Stainless steel is a non-porous material that resists the growth of bacteria, making it an excellent choice for applications where hygiene is paramount.

They find common use in chemical processing, as well as brewery and dairy processing. Their strong resistance to pathogens means that they are a great fit for the sterile environments of medical and pharmaceutical laboratories.

Plastic

Plastic plumbing fittings are regarded for their light weight and simplicity to install. There are three main plastics used to create plumbing fittings:

• Polyvinyl Chloride (PVC) is frequently used for cold water supply lines.
• Chlorinated Polyvinyl Chloride (CPVC) is suitable for hot water applications.
• Cross-linked Polyethylene (PEX) is highly flexible, and can be used in both cold and hot water systems.

What to consider when choosing a plumbing fitting?

There are some key considerations to make when selecting a plumbing fitting, to ensure a leak-free, efficient system – including…

Pipe size

Measure the exact diameter of the existing pipes accurately. If you wish to connect more than one pipe, take all measurements, as the fitting you require will need to accommodate both.

Plumbing pipes are often measured by their diameter. Here are some of the common pipe diameters:

• Domestic: internal supply pipes in households usually measure 15mm or 22mm in diameter.
• Commercial: internal commercial plumbing pipes often measure 28mm in diameter.
• Waste: to accommodate the passage of waste without getting clogged, waste pipes are usually 110mm in diameter.

Fit type

Depending on the fitting you require, you will need to consider the different types of fit. These are the most common fit types:

Slip Fit: sometimes referred to as push-fit, these are designed for a quick installation. They are pushed onto the end of a pipe, and have an internal mechanism, such as metal teeth, to create a secure, leak-proof connection

They are often used in residential plumbing, or temporary connections, as they can be easily disconnected and reused.

Threaded: these fittings use a screw-thread mechanism to connect pipes and form a tight seal. The thread can be either male (external) or female (internal). They are often used in metal piping systems, and are suitable for high-pressure systems due to their strong, secure connections.

Interested in learning more? Find out How to Identify a Thread with The Hosemaster…

Compression: compression fittings use a nut, a compression ring, and a compression seat to create a watertight seal. As the nut tightens, the ring is compressed against the pipe to create a secure connection. This design makes them easy to install, and can be disconnected and reused without damaging the fitting.

They are commonly used in connecting water supply lines to taps and toilets, or for low-pressure gas lines.

Soldered: also known as sweat fittings, these fittings are commonly used with copper pipes. The fitting and pipes are joined using solder and a heat source to create a permanent bond.

The strong, reliable bond created between them makes them ideal for use in both residential and commercial plumbing.

Crimp: used with PEX piping, a crimp fitting uses a crimp ring, which is placed over the pipe and fitting. 

A crimping tool is used to compress the ring, securing the connection. It is a quick, efficient method for fitting PEX piping together.

Glue: lastly we have glue, or solvent-weld, fittings. These are used with plastic pipes, such as PVC and CPVC. The pipes are bonded to the fitting using a chemical solvent that softens the plastic enough to allow the pieces to fuse together.

It is widely used in drainage and waste systems, where plastic piping is commonly used, as it creates a strong, permanent bond that is not easily broken.

Buy Now - Nuts & Olives Plumbing Fittings

Pressure and temperature

In order to cope with the conditions of water and waste transportation, plumbing fittings have to withstand specific temperatures and pressures. To avoid the risk of leaks and failures, you should take into account these two ratings:

Pressure rating: fittings must be able to withstand the maximum pressure of your system. This information will usually be provided by the manufacturer.

Temperature rating: fittings must be able to endure the temperature extremes of your system – especially hot water, or steam.

Find all your essential plumbing fixing supplies at The Hosemaster

At The Hosemaster we stock a huge range of plumbing fittings, ranging from ball valves and fixings to pipe fittings, couplers and reducers. We have decades of experience within the plumbing industry, which means you not only have access to superb supplies, but also expert advice when you need it.

If you have more questions throughout your buying journey, you can contact us online, or call 01282 604 002 to speak to one of our friendly members of staff.

Find non-return valves online today

For more information, advice, and useful product buying guides, check out The Hosemaster blog

Pipe Cutters: The Ultimate Guide | PVC vs Rubber Fuel Hose: Which Is Best for You? | What Are the Different Types of Valves?