Planning to make an upgrade and concerned about whether your new shower head will fit?
All modern shower heads have a universal 1/2″ NPT connection size. This means that any shower head will fit any shower arm.
Are all shower heads the same size?
While the threaded connection is the same, thanks to the NPT standard, the length, and diameter of the shower head will vary from manufacturer to manufacturer. Therefore, it is important to take measurements of your shower stall and the shower head you are replacing to ensure that the new shower head will fit. This advice holds true whether you are installing a fixed, handheld, or rain shower head.
Is NPT a global standard?
No, NPT is a standard used only in the United States. Other countries may have their own standards, such as the British Standard Pipe (BSP). We discuss this in more detail here.
Do shower arms also follow this standard?
The shower arm, a pipe that forms a connection between the main water line and the shower head, conforms to the NPT standard, ensuring that any shower head will fit on any shower arm.
What about shower hoses?
For a handheld shower head, in most instances, the hose has a 1/2″ connection. However, what differs from this to most shower arms is that the hose is set on a ball bearing to allow for a full 360-degree rotation to prevent it from kinking. The material of the fitting will vary from one brand to another, but the connection size will remain the same.
How do I know which shower head to buy?
The type of shower head, mount, and shape you decide to purchase will depend on personal preference and what is important in your showering experience.
Modern shower heads now come with various features and functions, including low-flow, high-pressure, number of spray patterns, self-cleaning nozzles, and even built-in filters to remove impurities from the water. Since they are interchangeable, there is no need to worry about the connection but rather about the features and functions that are important to you.
What about old homes?
The National Pipe Thread standard started in 1864 (source). Older homes that predate 1864 may not have the NPT standard and instead rely on a proprietary fitting. However, given that this is over 150 years ago, the plumbing fixtures were likely upgraded at some point. In the event they were not, a new shower arm would need to be installed on the main water line behind the wall to allow for a standard NPT connection.