The number of people working in the plumbing industry has increased by more than 60 percent over the last decade.

This increase has tapered slightly in recent years because of lower amounts of new construction.

There are currently more than 6,400 professionals working in the country. Many of these individuals are contractors who perform repairs and renovations in residential and commercial buildings.

Professionals are able to repair problems that people without training cannot handle. There are several distinct instances when it is necessary to call a professional plumber.

A home or business will require professional attention if problems with plumbing keep returning even after attempting informal repairs.

Minor changes such as replacing a washer, tightening a bolt or even cleaning pipes and traps could temporarily improve the performance of a fixture.

If the issue returns, then the problem is actually located somewhere else within the system.

Only an experienced and trained professional will have the knowledge necessary to locate and repair the problem.

The main lines are the primary pipes leading in and out of a building. They connect to the municipal plumbing system. Problems with the main lines will cause issues in more than one area of a building.

A common sign that there is a problem with the main lines is water failing to drain out of sinks and toilets.

A major blockage could result in wastewater from one basin backing up into another. Only a professional plumber should work with and repair the main lines in a building.

This is because incorrectly handling the lines could cause serious problems in the future, could violate building codes and could make the initial problem worse.

Problems with the water pressure in a building affect how drains, faucets and pipes work throughout the plumbing system.

Low pressure will cause water to move slowly and weakly out of a faucet. It could cause toilets to refill very slowly.

High water pressure could damage pipes and fixtures.

Issues with water pressure are usually indicative of large problems such as broken connections, leaks and even malfunctioning equipment.

A professional is normally required to restore the proper level of pressure in the pipes.

Water heaters and the pipes connected to the appliance could experience problems. Water heaters do require regular maintenance as well.

Water heaters use complex electronics in order to maintain the correct temperature and level of pressure inside of the tank.

Attempting repairs without training and experience could result in changes that throw the heater out of balance.

It is even possible to accidentally disable or remove safety features.

This could create a dangerous situation. The water could become hot enough to cause burns.

The pressure in the heater could also increase and cause an explosion.

Problems with water heaters will require the attention of a professional plumber.

Problems with pipes and plumbing systems could result in damage to the structure of a building.

This includes nearby walls, floors and even the foundation. Water will weaken materials over time and could cause a partial collapse.

It is important to call a professional plumber immediately if a problem is discovered that is causing structural damage to a building.