Energy Efficient Building Design Questions and Answers

Answer: C

Each climate calls for a different and largely incompatible response, which is why a design imported from one region performs badly in another. Identifying the climate is the first design decision and constrains everything after it.

Answer: D

Correct answer: 1-Q, 2-R, 3-P

Each device answers a particular sun path. The high midday sun on the south is intercepted by a horizontal overhang. The low oblique sun on the east and west needs vertical fins. And a north facade in the northern hemisphere receives only diffuse light, so it needs no shading at all - which is why north glazing can be generous.

Answer: A

The climate sets the strategy, the form and orientation are the free and cheapest decisions, the envelope refines them, and the plant is sized last for the load that remains. Sizing the plant first is how a badly formed building comes to need large machinery.

Answer: B

Correct answer: 1 and 2 only are correct

Statements 1 and 2 are correct: shading outside the glass stops the radiation before it enters, while an internal blind absorbs it inside the room. And thermal mass works by absorbing heat by day and releasing it to cool night air, which requires a large diurnal swing. Statement 3 has the climate wrong - evaporative cooling needs dry air to evaporate into, so it suits hot arid regions and fails in humid ones.

Answer: C

Correct answer: increasing the window to wall ratio on the west facade

West glazing takes the low afternoon sun, which is hard to shade and arrives when the building is already warm, so more of it raises the cooling load and the peak demand together. The other three all reduce the load: a cool roof reflects, insulation resists, and external shading intercepts.

Answer: D

Correct answer: an absorption chiller driven by waste heat

An absorption chiller is a machine with a working fluid, a pump and a heat source, so it is an active system however efficiently it uses waste heat. The other three are passive: earth tunnels, wind towers over water and night ventilation of exposed mass all work by moving air and exploiting temperature differences already present.

Answer: A

Orientation and form are decided first and cannot be corrected afterwards, so a building presenting its long facades east and west will suffer whatever its glass and its chillers. It is why the energy consultant must be engaged at concept rather than at tender.

Answer: B

Real buildings are occupied longer, kept cooler and filled with more equipment than any design assumption, and the gap is well documented. It is the reason simulations should be trusted for comparison rather than for absolute prediction.

Answer: C

Correct answer: both the assertion and the reason are true and the reason explains the assertion

Both are true and the reason gives the mechanism. The generation a building can carry is limited by the roof and facade available for it, so that ceiling is fixed early. Demand is what can still be reduced, and reducing it is what brings the two within reach of each other - usually more cheaply per unit than generation would.

Answer: D

It does minimise the envelope, which is what the reason states, but a deep plan then needs artificial light and mechanical ventilation for spaces that a shallower plan would daylight and ventilate freely. The optimum balances the two.