Building permits are required to erect, modify, remove, or repair all structures, commercially and residentially, in the City of Diamond Bar. This includes everything from new building construction to fences, fireplaces, and signs.

The most common permits required for new construction are:

  • Electrical permits for new electrical service equipment installation, existing service relocations, electrical service increases, and fixed appliance and equipment connections;
  • Mechanical permits for the addition, replacement, repair, or alteration of mechanical systems in structures. This includes gas lines, propane tanks, installation of sprinkler systems, and associated piping for flammable liquids; and
  • Plumbing permits for all plumbing work including water service, drains, water mains, sewage disposal systems, and related fixtures and appliances.

Building permits vary in cost and scope according to the type of construction proposed. Fees may vary due to the type and number of stories of the proposed construction.

  • Electrical permits are based upon the service amperage, number of circuits, and type of installations.
  • Mechanical permits are based upon valuation of work for mechanical systems or equipment.
  • Plumbing permits are based upon the number and types of fixtures, sewers, drains, and water service piping.


Contact Information
Inspection Hotline: 909.839.7027

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