Causes of Leaky Pipes and How to Fix Them

Causes of Leaky Pipes and How to Fix Them

Published by On-Demand Supplies on 3rd Nov 2020

A leaky pipe can be anything from slightly annoying to a full-blown catastrophe should it lead to a burst and flood. Obviously, some areas will be more susceptible to leaks than others, but a leak is a leak and needs to be dealt with, with most common causes and  repair suggestions below. 


Most modern pipework you’ll find is either plastic or copper. Copper pipework has a projected lifespan of between 20-25 years (though this may be lower depending on how your area chemically treats your drinking water). If your copper pipe is more than 20-30 years old then there is a higher risk of corrosion, eventually leading to holes and leaks.

Joint Damage

The joints and bends are the most vulnerable parts of a pipework system. Joints are generally placed to connect shorter sections together. The main causes of joint damage are excess water pressure, extreme temperatures, or something being constantly forced against a pipe or connection (most commonly under the sink in bathrooms and kitchens). Minor building subsidence over time can cause pipes to move, minutely shifting the joints each time causing joint failure and leaking. When this happens the joint will require replacing and/or if a compression or push fit fitting, a new fitting seal should be replaced.

Seal Degradation

Rubber seals on push-fit fittings may feature at various points in your pipework system as they are required to keep joints and connections watertight. Even the best rubber seals can degrade or dry out over time causing cracks which will eventually lead to leaks. Other types of seals that can fail are olives fitted in brass compression fittings, although tightening the brass nuts will often re-seal the fitting

Excess Water Pressure

Water pressure is different in every home even though each building is connected to the municipal water supply. A power shower is going to put more pressure on the pipework than a regular shower, for example. The higher the pressure, the greater the risk of leaks. In mild cases, sporadic leaks happen, particularly immediately after the water flow stops. At its worst, extremely high water pressure can cause a burst pipe. A plumber is able to test the water pressure and adjust accordingly.

Poor Plumbing

It’s just a fact that sometimes a plumbing job is not done well. Even small mistakes in pipe laying can lead to big water damage. It might be poor connections or incorrect use of backflow devices (required to help water flow against gravity), or just shoddy workmanship. A reputable plumber will access and inspect your entire pipework system to identify where repairs or updates need to be made.

Hole in a water pipe

It is very rare for a hole to appear in a water pipe for no reason. This is usually due to it being punctured by a nail or "pinched" by tightening something onto the pipe. The main reasons for this are fitting shelves or pictures, repairing floorboards or plasterboard. Often the hole will go unnoticed as it may be partly sealed by the nail for instance. It is only when wet patches start to appear that a minor leak may become an urgent issue. If the hole is in the central heating pipework and is a small leak it may be that the pressure in the heating system drops over a period of time and the boiler shuts down for safety reasons. The only way to overcome this is to find the leak, drain the entire system, repair the damage, repressurise and bleed the system

How to Repair a Damaged Water Pipe

There are a couple of different devices you can buy to repair a hole in a pipe

Solder Ring Pipe Repair Patch

This is a copper patch which is placed over the hole and soldered in place. These are available in 15mm and are only designed to work over small holes on a straight piece of pipe. The pipework within several metres of the damage will need to be drained to allow the pipe to be heated to a high enough temperature.

The pipe should be thoroughly cleaned with wire wool and, ensuring the hole has caused no raising of copper, a high quality flux applied to the surface, the patch applied over the hole and heated until the solder melts and flows smoothly out of the edges.

Pipe Repair Coupling

These are more versatile than a repair patch and are available in 15mm and 22mm. They are basically an extended brass compression coupling that is used to span between two pipes after a damaged section has been removed.