What are four ways to fabricate a duct section from duct board?

What are four ways to fabricate a duct section from duct board?

• A. Single-piece duct, triple-piece duct, corner duct, wrap duct
• B. Flat duct, curved duct, square duct, round duct
• C. One piece duct, two-piece duct, two piece L duct and four piece duct
• D. Basic duct, extended duct, modular duct, standard duct

Answer: (C)

Fabricating a duct section from duct board is about turning flat panels into a working run by cutting and joining pieces to fit the desired shape. A straight run can be made from a single piece of duct board. If a bend is needed without using a separate elbow piece, you can form it by joining two pieces to create a simple curved transition. For more abrupt turns, a two-piece L duct uses two pieces to form a 90-degree elbow. For longer or more complex transitions, a four-piece configuration uses four pieces to build the required geometry. In practice, you cut the panels to size, shape the edges to form the joints, and seal with adhesive and fasteners (often with mastic and foil tape) to prevent air leaks. The other options describe shapes or terms that aren’t standard fabrication methods from duct board.

Fabricating a duct section from duct board is about turning flat panels into a working run by cutting and joining pieces to fit the desired shape. A straight run can be made from a single piece of duct board. If a bend is needed without using a separate elbow piece, you can form it by joining two pieces to create a simple curved transition. For more abrupt turns, a two-piece L duct uses two pieces to form a 90-degree elbow. For longer or more complex transitions, a four-piece configuration uses four pieces to build the required geometry. In practice, you cut the panels to size, shape the edges to form the joints, and seal with adhesive and fasteners (often with mastic and foil tape) to prevent air leaks. The other options describe shapes or terms that aren’t standard fabrication methods from duct board.