Reading a house floor plan's orientation involves identifying how rooms align with compass directions. Key elements include window placement, doorways, and outdoor spaces relative to north, south, east, and west. North-facing rooms typically receive consistent morning light, south-facing rooms get intense afternoon sun, east-facing spaces have early light, and west-facing areas experience longer evening exposure. Understanding this helps assess natural light availability, ventilation efficiency, and energy consumption.

The importance of orientation lies in its impact on livability and sustainability. Studies by the U.S. Department of Energy (DOE) show that properly oriented homes can reduce heating and cooling costs by up to 20%. South-facing windows maximize passive solar gain, lowering reliance on artificial heating during winter. Conversely, west-facing rooms may require shading to mitigate summer heat gain, as noted in a 2021 study by the National Association of Home Builders (NAHB). Additionally, east-facing breakfast nooks or west-facing backyards often enhance usability, with 68% of homeowners prioritizing natural light in a 2022 survey by the National Association of Realtors (NAR). Proper orientation also aligns with zoning laws in some regions, ensuring compliance with solar panel or green building requirements. Data from the DOE further indicates that energy-efficient designs, influenced by orientation, can increase home resale value by 3-5%. Thus, analyzing a floor plan's orientation is critical for cost savings, comfort, and marketability.