Heating/cooling (HVAC), electric, and plumbing are generally considered the "major" building systems. Related systems include, but are not limited to the following:

• HVAC
  • Whole house vacuum system

  • Humidifier and dehumidifier
  • Mechanical venting (attic vents, bathroom vents)
  • Radiant heating
  • Make-up air
• Electric
  • Security system

  • Backup generator
  • Solar cells
  • Low voltage systems (undercabinet lighting, telephone, intercom)
  • Cable/satellite
  • Speaker wiring
  • Structured wiring (Cat-5)
• Plumbing
  • Radiant heat

  • Water softener or water filter
  • Swimming pool
  • Irrigation

Systems installation usually starts after framing is substantially complete. In many cases outside utilities work (sewer, electric service upgrades, and water service) is completed while framing is underway.

It is vitally important to consider the order in which systems are installed - misfiguring could result in conflicts between the trades that require work to be torn out and redone. IN general, installation starts with HVAC, then plumbing, and finishes with electric. Some circumstances may result in this chain of events being altered.