Environment and Sustainability
Environment and Sustainability tests whether you can reduce demand before adding technology. For SLIA Part I, expect passive design, climate response, energy, water, materials, waste, and Sri Lankan regulatory or rating contexts such as the National Environmental Act, Sustainable Energy Authority efficiency guidance, and GreenSL rating principles. The exam favours measured reasoning: orientation, shading, ventilation, and detailing before solar panels.
Core rules and concepts
- Sri Lanka’s wet zone receives roughly over 2,500 mm annual rainfall; the dry zone under about 1,750 mm; intermediate zones lie between. Design for driving rain, humidity, and monsoon direction.
- Passive hierarchy: site and orientation, form and shading, envelope, ventilation, then active systems.
- In warm-humid climates, prioritise shade, cross-ventilation, dehumidification, and rain protection; use thermal mass carefully.
- Water strategy includes harvesting, storage, treatment, low-demand fittings, and infiltration.
- Material choices consider embodied energy, durability, local availability, and end-of-life; avoid greenwash claims.
Worked example
A west-facing office in Colombo overheats. First reduce exposure with deep shading, screens, or a buffer zone; then improve cross-ventilation and ceiling height; then specify efficient lighting and cooling. A photovoltaic array may be added, but it does not excuse a glass box with unshaded west glazing. Reason from load reduction to supply, and state the assumptions used for any energy comparison.
Traps
- Treating “sustainable” as a product checklist.
- Copying dry-zone thermal-mass strategies into humid Colombo.
- Ignoring maintenance and user behaviour.
- Claiming savings without assumptions or units.