The standard residential wall thickness can vary depending on the construction method, building codes, and the region where the home is located. In the United States, for example, the most common wall thickness for interior walls is typically 4.5 inches (11.43 cm) for walls framed with 2x4 studs. This dimension allows space for insulation and drywall, resulting in a finished wall thickness of approximately 4.5 inches.
For exterior walls, the standard thickness often increases to 6 inches (15.24 cm) when using 2x6 studs to provide extra space for insulation, as well as to enhance energy efficiency and structural stability.
However, it's important to note that wall thickness can vary based on the specific design of the house, local building codes, and construction practices. Additionally, some modern homes may use alternative building materials or construction techniques that could result in different wall thicknesses.
If you're planning to build or renovate a home, it's essential to consult with a local architect, contractor, or builder to determine the appropriate wall thickness for your specific project and to ensure compliance with relevant building codes and regulations.