Technical Abilities (Trade-Related Aptitude)
Trade-related aptitude for Civil checks measurement, estimation, drafting awareness, construction materials, tools, safety and simple quantity take-off. Questions test whether you can apply standard measurement rules and unit conventions to site-like situations.
Core rules and concepts
- Measurement: IS 1200 governs measurement of civil works. Length is measured in m, area in m², volume in m³, and steel reinforcement usually in kg or tonne. Deduct openings above specified sizes from masonry and plaster areas.
- Brickwork: nominal brick size with mortar is commonly 200×100×100 mm; modular brickwork is often taken as 500 bricks per m³ as a rule of thumb, then adjusted for actual size and wastage.
- Concrete and plaster: volume = length × breadth × height; plaster quantity depends on thickness. Add wastage separately and do not mix dry and wet volumes without applying the bulking factor.
- Steel: bar bending schedule gives cut length, number, diameter and weight; unit weight of steel is approximately d²/162 kg/m for diameter d in mm.
- Safety: use helmets, harnesses and scaffolding guards; never measure from an unsafe edge.
Worked example
A brick masonry wall is 10 m long, 3 m high and 0.23 m thick. Volume = 10×3×0.23 = 6.9 m³. At 500 bricks/m³, nominal bricks = 6.9×500 = 3450. With 5% wastage, order 3450×1.05 = 3622.5, so approximately 3623 bricks.
Traps
Measuring masonry in m² instead of m³, forgetting to deduct large openings, using actual brick size where nominal size is required, and ignoring wastage in material estimates.