Final answer:
Heavy duty ladders used by contractors and maintenance workers are typically extension ladders due to their durability, adjustability, and ability to support more weight.
Step-by-step explanation:
The type of ladder that is considered heavy duty and is commonly used by contractors and maintenance workers is the extension ladder.
Extension ladders are designed to reach high places and are adjustable in length, typically using overlapping sections that can be extended and locked in place.
These ladders are especially useful for tasks involving the exterior of buildings, such as painting, roofing, and other types of outdoor maintenance work. They are chosen for their durability, stability, and the ability to support more weight compared to other types of ladders such as step ladders, telescoping ladders, and platform ladders.
A heavy-duty ladder used by contractors and maintenance workers is an extension ladder. Extension ladders are designed to be adjustable in length and can reach higher heights than step ladders or other types of ladders.
They are typically made of sturdy material like aluminum or fiberglass to support the weight of a person and any tools or equipment they may be carrying.