You have lived in your house for a few years and now you notice changes erupting in the plumbing system. The faucets are leaking, the taps are dripping, the drainage system is almost falling apart but most importantly, you notice the plumbing pipes change their colours. These pipes at your home could be made of copper, iron or PVC. But what causes the plumbing pipes to change their colours?

Copper Pipes

Copper pipes have high heat tolerance and are proven to be durable for a long time. Copper is a metal that can conduct hot or cold water through it. The issue it can bring to a household is oxidization due to reaction with the oxygen and air as well as other acidic components of smog, smoke and rain. The World Health Organization states 2.0 milligrams of copper per litre as the maximum level permitted to be found in water. But note that even copper levels in water that is over 1.0 milligrams can cause health issues. Here are the colours you would notice when your copper pipes change from its original colour.

Blue or Bluish-green

When the copper pipe is exposed to changes in the environment, a green layer is created over the pipes. You may also notice blue or greenish-blue water pour from the taps. This is because the pipe corrodes and the copper dissolves into the water. Look for any pinhole leaks, cracks or pipe bursts that may have appeared because of a pipe wall becoming thinner. If the damage does not appear too severe, you plug them by using different methods like a solder, a repair clamp or a chemical sealant. Alternatively, call a plumber over to check the pipes and to replace any damaged portion. The plumber can check the pipes in the house and replace any pipes that are in its last days of use.


The other colour your copper pipes could turn into is black. This can be noticed when the presence of sulphur levels in the water is high. The plumbing pipes could even turn black because of other chemicals in the air like sewer gas because the home’s sewer line failing. There can even be instances when the copper pipe comes in contact with other non-compactible metals, one of them being galvanized steel. The pipes also turn black if cheap copper versions were used during installation by the builder. Cheap copper contains high amounts of impurities.

Iron Pipes

Iron pipes react with the moisture and oxygen in the air in a process called oxidation. It causes the formation of rust over the iron. You will also notice interiors of the pipes carrying hot water rust faster than the ones carrying cold water. This occurs because of the increased level of minerals and chemicals in hot water that oxidize the iron pipes. Iron release from corroded pipes can lead to health-damaging issues to arise.

Polyvinyl Chloride (PVC)

The PVC pipes are susceptible to an increasing growth of mould in the house. It causes the creation of a bluish-green film over the pipe which can be removed with tactful home remedies.

In a worst-case scenario, if you come across complete pipe failure, you would need to book an appointment to perform an emergency plumbing maintenance service. 24 Hour Plumbing Heating engages trained technicians for plumbing and heating services for home maintenance, repairs and replacement needs. Need support? Book an appointment.