​A measured survey involves taking precise measurements of sites or buildings to create accurate drawings or models at a reduced scale. These surveys are typically specified with agreed-upon levels of detail, accuracy tolerances, scale, delivery times, and costs. They serve as the foundational data for subsequent planning, design, and development phases. 

According to the Royal Institution of Chartered Surveyors (RICS), measured surveys are designed for use by land, engineering, and measured building surveyors, as well as clients who specify their own surveys. The RICS standard, “Measured Surveys of Land, Buildings and Utilities,” provides comprehensive guidelines on aspects such as project information, survey accuracy, control, coordinate grids, datums, topographic surveys, measured building surveys, underground utility surveys, and monitoring and deformation.

These standards ensure that measured survey data are accurate, comprehensive, and reliable, which is essential for projects requiring meticulous documentation, such as heritage conservation, detailed architectural renovations, or large-scale commercial developments.

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