Maintains and repairs light fixtures, receptables and switches; replaces light bulbs; maintains generators and motors; oils and cleans motors; troubleshoots and makes electrical repairs not requiring a license; maintains and makes minor repairs to various types of heating, refrigeration and air-conditioning equipment, such as components, pumps, fans, humidifiers, electric motors, and heat exchangers. Performs construction or renovation of buildings or additions to existing structures; erects and maintains scaffolds, sheds, forms, frames, fences and other structures; alters and repairs doors, floors, partitions, stairways, windows, screens, and other fixtures; fits and glazed glass in windows and doors; maintains and repairs roofs.