BArch Bachelor of Architecture Building Materials & Construction Technology 2 — Questions and Answers
Question 1: What does ASTM designate for standard Type I/II Portland cement, the most commonly used cement type in US construction?
- ASTM C150 (Correct answer)
- ASTM C270
- ASTM C33
- ASTM E119
Correct answer: ASTM C150
ASTM C150 is the standard specification for Portland cement, with Type I being general-purpose and Type II offering moderate sulfate resistance, both widely used in US construction.
Question 2: In steel construction, galvanizing protects steel from corrosion by which mechanism?
- Cathodic (sacrificial) protection — zinc corrodes preferentially to protect the steel (Correct answer)
- Creating a hermetic seal that blocks oxygen
- Increasing steel's chromium content
- Applying a thick polymer coating
Correct answer: Cathodic (sacrificial) protection — zinc corrodes preferentially to protect the steel
Zinc in galvanizing is anodic to steel, meaning zinc corrodes sacrificially — it is consumed before the underlying steel, providing long-term corrosion protection.
Question 3: Which masonry unit is hollow, lightweight, and most commonly used for load-bearing and non-load-bearing walls in US commercial construction?
- Concrete Masonry Unit (CMU) (Correct answer)
- Solid clay brick
- Adobe block
- Autoclaved aerated concrete (AAC)
Correct answer: Concrete Masonry Unit (CMU)
CMU (concrete block) is the dominant masonry unit in US commercial construction due to its hollow cores (which reduce weight and allow reinforcing/grouting), low cost, and versatility.
Question 4: What is the primary purpose of a vapor retarder in a building assembly?
- Limit moisture diffusion through the assembly to prevent condensation within the wall (Correct answer)
- Prevent liquid water infiltration from rain
- Block air movement through the building envelope
- Provide a fire-resistant barrier
Correct answer: Limit moisture diffusion through the assembly to prevent condensation within the wall
A vapor retarder limits the diffusion of water vapor through a wall, ceiling, or floor assembly, preventing condensation from forming within the insulation or structure.
Question 5: In curtain wall systems, what is the function of the pressure plate and cover cap assembly?
- Clamp the glazing to the mullion and provide a finished exterior surface (Correct answer)
- Structurally connect the curtain wall to the floor slabs
- Drain condensation from the glazing pocket
- Provide thermal break between interior and exterior
Correct answer: Clamp the glazing to the mullion and provide a finished exterior surface
The pressure plate bolts to the mullion to mechanically capture the glass or panel edge, while the snap-on cover cap conceals the fasteners and provides the finished exterior appearance.
Question 6: What is the key structural difference between engineered lumber products (LVL, PSL) and dimension lumber?
- Engineered lumber has fewer defects and more consistent, predictable strength properties (Correct answer)
- Dimension lumber is stronger in compression
- Engineered lumber cannot be used structurally in wet conditions
- Dimension lumber has higher shear strength
Correct answer: Engineered lumber has fewer defects and more consistent, predictable strength properties
Engineered lumber products like LVL and PSL use veneers or strands bonded under pressure, distributing natural defects so properties are more uniform and predictable than sawn dimension lumber.
BArch Bachelor of Architecture Building Materials & Construction Technology 2
What does ASTM designate for standard Type I/II Portland cement, the most commonly used cement type in US construction?