In general, Mechanical Contractors are responsible for heating or cooling systems, cooling, piping and plumbing. A Mechanical Contractor has a variety of skills which, when put together, consist of a very large part in creating and maintaining a building so that it fulfills its purpose. Anything with mechanical components will require the attention of a Mechanical Contractor, both for production, installation, or ongoing maintenance and repairs.

There are many potential occupational fields for Mechanical Contractors. Temperature control in a building is a big part of their work, especially because heating systems or air conditioners are needed in new buildings to maintain temperatures at a comfortable level. The Mechanical Contractor will look at the building and determine the best method needed for heating and cooling. They need to consider the practical installation, cost, and energy efficiency of a system to decide what is most suitable for a particular project. Mechanical contractors are usually also responsible for the ongoing maintenance of the systems they install.

A Mechanical Contractor generally takes a supervisory role in a construction project. It is their duty to supervise mechanics and make sure everything is running smoothly. Their responsibility may involve ensuring that the mechanical elements of the building are installed on time and within the required budget. This can also include subcontractor scheduling and workload allocation and delegation.