Copper Pipes

Copper pipes are the most commonly used plumbing pipes for residential and commercial water supply distribution. Copper plumbing pipes, or tubes, as they are called in the plumbing industry, have been used for potable hot and cold-water distribution for many years, and are an approved material for water distribution in every municipality.



Types of Copper Pipes

Copper pipes are sized by their nominal diameters, one-eighth inch less than the outside diameter. Tube diameters start from 3/8" and go up to 2", in 1/8" increments. There are two types of copper tubing:

  • Hard, or tempered
  • Soft, or annealed.

Hard copper tuning is sold in 10 or 20-foot straight lengths. It is more difficult to install because it is rigid. Therefore, it is used primarily in new home construction.

Soft copper tubing is sold in coils of 60 to 100 feet. Soft copper tubing is easy to cut and size and install in older houses where there are many obstacles to overcome. Soft copper tubing may be used to connect gas lines to appliances or to connect water pipes to fixtures.

Copper Pipe Series

Copper tubing is extremely durable and corrosion resistant, lasting for many years. Copper pipes are used for various purposes, and are sold in three different series:

  • K - thickest wall width; used for underground exterior purposes such as between the water main and the meter
  • L - multi-purpose pipe
  • M - thinnest walled; used behind walls as the main distribution system within the house.

In some municipalities, M series copper plumbing tubes violate building codes and not allowed to be used.

Joining Copper Pipes

Lengths of rigid copper plumbing pipes are joined together by soldering, which is referred to as sweating the pipes. Connectors are required to join pipes in various configurations such as a:

  • T-juncture
  • 90 degree bend
  • Straight connector.

Installing Copper Pipes: Factors to Consider

Lead pipes found in older homes frequently contain toxic substances. However, copper pipes, when used for water supply plumbing, is non-toxic, provided the solder is not lead-based. Copper pipes are comparable in cost to other plumbing tubing.

The only instance in which copper tubing should not be installed is when pH of water is below 6.5 (acidic), as it will corrode the pipes; however, this rarely occurs because most municipalities maintain the pH of the public water supply between 7.2 and 8.0.