Other Skilled Trades Masonry 2 — Questions and Answers
Question 1: What is the minimum required overlap (lap) for brick courses at corners and in running bond pattern?
- 1/4 of the brick length
- 1/3 of the brick length (Correct answer)
- 1/2 of the brick length
- 2/3 of the brick length
Correct answer: 1/3 of the brick length
Minimum 1/3 overlap of the brick length is required at courses to ensure proper load transfer and structural integrity in masonry walls.
Question 2: What material is used to create a control joint in a concrete block (CMU) wall to control cracking?
- Metal Z-bar
- Rubber or foam backer rod with sealant (Correct answer)
- Mortar with added fiber
- Galvanized mesh
Correct answer: Rubber or foam backer rod with sealant
Control joints in CMU walls are created by raking out the mortar joint and filling with a backer rod and flexible sealant to allow for thermal movement.
Question 3: What is the primary purpose of cavity wall construction in masonry?
- To reduce brick costs
- To provide a drainage plane and thermal break between wythes (Correct answer)
- To increase the speed of construction
- To allow for electrical conduit installation
Correct answer: To provide a drainage plane and thermal break between wythes
A cavity wall creates a drainage plane between the outer and inner wythes, preventing moisture from crossing into the interior and improving thermal performance.
Question 4: Which ASTM standard governs the specification for mortar for unit masonry?
- ASTM C90
- ASTM C270 (Correct answer)
- ASTM C62
- ASTM C216
Correct answer: ASTM C270
ASTM C270 is the standard specification for mortar for unit masonry, defining the mix proportions and minimum properties for Types M, S, N, and O mortar.
Question 5: What is 'tuckpointing' in masonry repair?
- Adding new bricks to an existing wall
- Removing deteriorated mortar joints and filling with new mortar (Correct answer)
- Sealing brick surfaces with waterproofing
- Installing wall ties in existing masonry
Correct answer: Removing deteriorated mortar joints and filling with new mortar
Tuckpointing involves removing deteriorated mortar from joints to a depth of 3/4 inch and replacing it with fresh mortar to restore the wall's integrity and appearance.
Question 6: What type of lintel is most commonly used over openings in brick veneer walls in US construction?
- Wooden lintel
- Stone lintel
- Steel angle lintel (Correct answer)
- Precast concrete lintel
Correct answer: Steel angle lintel
Steel angle lintels (shelf angles) are most commonly used over openings in brick veneer walls because they are strong, durable, and easy to install.
Other Skilled Trades Masonry 2
What is the minimum required overlap (lap) for brick courses at corners and in running bond pattern?