To determine the orientation of a residential building, use a compass or digital tool to identify north. Observe the roof slope and window placement relative to cardinal directions. South-facing windows in the Northern Hemisphere typically maximize natural light and heating. Check shadows at solar noon; longer shadows indicate north-facing sides.

Optimal building orientation enhances energy efficiency by leveraging passive solar gain. South-facing windows in the Northern Hemisphere can increase heating efficiency by up to 30% (U.S. Department of Energy, 2020). Studies show well-oriented homes reduce heating and cooling costs by 20–30% annually (ASHRAE, 2018). In regions like California, east-west orientations minimize glare and heat gain, improving comfort (California Energy Commission, 2019). roof slope and window alignment also affect windbreak effectiveness, reducing cooling demands by 15–25% (DOE, 2021). Data from the International Energy Agency (IEA) confirms that 90% of new U.S. homes now prioritize solar orientation during construction, reflecting its cost-saving and environmental benefits. Ignoring orientation can lead to higher energy bills and reduced indoor comfort, underscoring its critical role in sustainable design.