Methodology in 3D laser scanning of a farmhouse

The urgent need to improve the quality in the refurbishment of traditional buildings has led to the adoption of many innovative technologies. 3D laser scanning is a non-destructive technique used in the study of architectural heritage. It consists of producing millions of accurate 3D points with a very high point density  in a short time. For this reason, it is a valuable alternative or complementary technique for classical topographical measurements based on total station or digital photogrammetry. To get the complete 3D model, multiple shots must be taken from different directions that provide data from all sides of the building. These scans are integrated into a common reference system so that through a process of aligning the information obtained in all the stations, a complete model is achieved in a single file. This model faithfully reproduces the current volume of the building, including its deformations and collapses, and provides very precise information from which to make its geometric survey. With the aim of making a graphic survey of the farmhouse located in the UPV campus, current headquarters of the CEDAT Foundation (Service for Attention to Students with Disabilities), a 3D laser scan was carried out in March 2019. This paper describes the methodology of laser scanning, the specific step during scanning and the possibility of create 2D documentation from 3D model point clouds.