What is the most commonly used type of copper pipe for domestic plumbing installations?

The most commonly used type of copper pipe for domestic plumbing installations is Grade B (R220 half hard lengths). This type of copper pipe strikes a balance between flexibility and rigidity, making it ideal for various plumbing applications, such as water supply lines and heating systems.

Grade B copper pipe is half-hard, which means it can be easily bent and shaped during installation while still being strong enough to withstand the pressures typically found in domestic plumbing systems. This makes it convenient for plumbers when maneuvering pipes around obstacles in existing structures.

In contrast, other grades such as Grade A (soft lengths) are more malleable but less durable when it comes to withstanding pressure over time. Grade X (R250 half hard lengths) and Grade C (R260 hard lengths) pipes are typically less commonly used in domestic settings because they may not provide the necessary balance of workability and strength for typical home plumbing tasks. Thus, Grade B's characteristics make it the preferred choice for a variety of domestic plumbing installations.