The question on the presence, the magnitude and the significance of deformation of objects evolves with the increasing use of TLS from a pointbased one to a space-continuous one. Here, a method based on the epochal approximation of point clouds with tensor product B-spline surfaces is presented. The introduction of the estimated control points in the congruency model results in a statistically sound statement on the presence of space-continuous deformation. This work investigates the impact of geometric structures with a spatial extent of several centimeters on the surface modelling and the outcome of the deformation analysis, obtained within the framework of the outlined method. The stochastic information originating from the reference network and TLSmeasurements is rigorously propagated through the study. The applicability of this method to real-world structures with spatial scales of several tens of meters is researched, using an aqueduct arc and an industrial chimney as test objects.