In traditional roof and truss construction, the projecting structural piece provided to support a truss at the wall junction is commonly known as what?

Introduction / Context:
In masonry and timber roof construction, trusses require intermediate bearing or support where they rest on walls or columns. A projecting piece that extends out of the wall face to carry load is traditionally called a corbel. Recognizing the distinction between decorative elements and load-bearing projections is key in building terminology.

Given Data / Assumptions:

• The question refers to a projecting structural member, not merely decorative moldings.
• The function is specifically to support a truss (a roof framework component).
• Common architectural elements like cornice, coping, frieze, and lintel have different purposes.

Concept / Approach:
A corbel is a masonry projection from a wall face that acts as a bracket to support loads such as trusses, beams, balconies, or arches. It transfers load back into the wall. This is distinct from cornice (decorative molding at roofline), coping (protective cap of a wall), frieze (decorative horizontal band), or lintel (beam across openings).

Step-by-Step Solution:
Identify requirement: load-bearing projection for truss.Match to correct terminology: corbel is the element that projects to support loads.Other listed terms are decorative or serve different functions.Therefore, the correct answer is corbel.

Verification / Alternative check:
Architectural references in construction handbooks define corbel as a structural masonry bracket, distinct from decorative cornices and friezes.

Why Other Options Are Wrong:

• Cornice: decorative projection, not load-bearing for trusses.
• Coping: top protective covering of walls against rain.
• Frieze: horizontal decorative band between cornice and architrave.
• Lintel: horizontal beam over openings like doors and windows; not projecting support for trusses.

Common Pitfalls:
Confusing lintel (structural but horizontal above openings) with corbel; misusing decorative terms for structural support elements.

Final Answer:
Corbel