Environmental Control and Sustainability
What the domain tests
Environmental Control and Sustainability tests passive design, energy and water efficiency, and the environmental approval process. The focus is on measurable performance, not green labels alone.
Core rules
- Climate response: Pakistan includes hot-dry, hot-humid, composite and cold zones. Hot-dry design uses thermal mass, shading, courtyards and evaporative cooling; hot-humid design prioritizes cross-ventilation and low thermal mass.
- Passive design: orient the building to control solar gain, shade west and south glazing, insulate the roof, use night ventilation and bring daylight into occupied spaces without glare.
- Energy: the Building Energy Code of Pakistan and NEECA guidance promote efficient envelopes, lighting and HVAC. Set indoor temperatures around 24-26 C where appropriate, and consider solar PV and net metering.
- Water: low-flow fixtures, rainwater harvesting, greywater reuse and xeriscaping reduce demand.
- Environmental approvals: under the Pakistan Environmental Protection Act 1997, projects may need an initial environmental examination or a full environmental impact assessment, with NEQS compliance and public consultation where required.
Worked example
A 100 sq m roof receives 50 mm of rain. Gross volume = 100 x 0.050 = 5 cu m = 5,000 litres. With a runoff coefficient of 0.8 and filter efficiency of 0.85, usable yield = 5,000 x 0.8 x 0.85 = 3,400 litres. That yield, not the gross rainfall, should size the tank.
Traps that cost marks
Applying hot-humid strategies to a hot-dry site. Ignoring orientation and shading. Treating EIA as a post-design formality. Confusing IEE and EIA thresholds. Claiming sustainability from product labels without performance data.