Building Technology and Construction
Building Technology and Construction tests how a building stands up, keeps water out, services its users, and can be built safely in Sri Lankan conditions. Expect questions on structural action, load paths, reinforced concrete, masonry, foundations, damp-proofing, roofs, services, tolerances, and buildability. The exam rewards details that show you understand construction sequence and failure modes, not just material names.
Core rules and concepts
- Follow the load path from slab to beam, column, foundation, and ground; every transfer must be continuous and braced.
- Reinforced concrete needs adequate cover, compaction, curing, and water-cement ratio; aggressive coastal and wet-zone conditions demand durability detailing.
- Masonry is strong in compression but needs lintels, ties, and movement joints; avoid unbraced slender walls.
- Water control is layered: roof pitch, gutters, flashing, damp-proof course, tanking, and drainage.
- Buildability includes access, sequencing, temporary works, and tolerance clashes.
Worked example
A 6 m simply supported reinforced-concrete beam is proposed. Preliminary depth is often taken as span/12 to span/15, giving about 400–500 mm, with width around 225–300 mm. That is only a starting point: the final section must be checked for bending, shear, deflection, and cover, and the supported masonry load must be traced. If the beam also carries a 230 mm brick wall, check its deflection and the wall’s support detail; otherwise cracking may appear.
Traps
- Sizing members from rules of thumb without checks.
- Ignoring coastal salt, termites, or monsoon-driven rain.
- Mixing units or specifying impossible tolerances.
- Treating waterproofing as a single membrane rather than a system.