What Is the Difference Between PVC Imperial and PVC Metric?

They are used to join PVC pipes together to form a complete piping system. PVC fittings come in two different measurement systems: imperial and metric. Understanding the differences between imperial and metric PVC fittings is essential to choose the right fittings for your piping system. In this blog, we will explore the differences between imperial and metric PVC fittings and their applications.

Imperial PVC Fittings

Imperial PVC fittings are manufactured in inches and are widely used in North America, the United Kingdom, and other countries that use the imperial system of measurements. The imperial measurement system has been in use for hundreds of years and is based on feet, inches, and fractions of inches.

Imperial PVC fittings are usually manufactured in standard sizes ranging from 1/2 inch to 10 inches in diameter. The outside diameter of imperial PVC fittings matches the nominal size of the pipe, and These fittings typically have a slightly thicker wall and a higher pressure rating compared to metric fittings.

Imperial PVC fittings are known for their durability and chemical resistance. They are commonly used in a wide range of applications, including water supply, wastewater treatment, and chemical processing.

Metric PVC Fittings

Metric PVC fittings are manufactured in millimeters and are widely used in Europe, Asia, and other countries that use the metric system of measurements. The metric measurement system is based on meters, centimeters, and millimeters and has been in use for over 200 years.

Metric PVC fittings are manufactured in standard sizes ranging from 16 mm to 250 mm in diameter. The outside diameter of metric PVC fittings matches the nominal size of the pipe, and These fittings typically have a lower pressure rating but have a thinner wall, making them lighter and easier to handle.

Metric PVC fittings are known for their durability and chemical resistance, similar to imperial PVC fittings. They are commonly used in a wide range of applications, including water supply, wastewater treatment, and chemical processing.

Differences between Imperial and Metric PVC Fittings

There are several differences between imperial and metric PVC fittings, including measurement system, size, and compatibility.

Measurement System

The most obvious difference between imperial and metric PVC fittings is the measurement system used to manufacture them. Imperial PVC fittings are manufactured in inches, while metric PVC fittings are manufactured in millimeters. 

Size

The size of imperial PVC fittings ranges from 1/2 inch to 10 inches in diameter, while metric PVC fittings range from 16 mm to 250 mm in diameter. This difference in size range means that metric PVC fittings are typically smaller in size than imperial PVC fittings.

Compatibility

Imperial PVC fittings are not compatible with metric PVC pipes, and vice versa. This means that imperial PVC fittings can only be used with imperial PVC pipes, and metric PVC fittings can only be used with metric PVC pipes.

Fig.1: Difference in the dimension of Imperial and Metric pipe

Choosing the Right PVC Fittings

The choice between imperial and metric PVC fittings depends on the piping system you are using. If you are using imperial PVC pipes, you should use imperial PVC fittings, and if you are using metric PVC pipes, you should use metric PVC fittings.

It is also important to consider the size of the fittings you need. PVC fittings are manufactured in standard sizes, so it is essential to choose the right size for your piping system. You should also consider the type of application the fittings will be used for and choose fittings that are appropriate for that application.

Is there any chance to match imperial fittings to the metric pipe and vice versa?

It is not possible to directly match an imperial fitting to the metric pipe as they are different measurement systems and have different dimensional specifications. You would need an adapter to connect the two, which can be obtained from plumbing supply stores. However, it is important to note that the compatibility and suitability of the adapter depend on the specific application and conditions, and it is advisable to consult a professional plumber or engineer to ensure a safe and secure connection.