Measured Building Surveys Best Rated London Surveyor If a true-to-scale, accurate representation of your land or building is what you''re trying to find you''ve come to the right place. Callidus is one of the UK''s premier specialist measured building surveyors. We offer you a focused suite of professional services: Building Surveys Topographic Surveys Movement Monitoring Laser Scanning Callidus employs only in-house trained surveyors and routinely produces the greatest accuracy surveys achievable. When it comes to measured building surveys, whether you''re located in London, the Home Counties or more than, Callidus Surveys are here to help, bringing our years of expertise and knowledge to offer a fast, high quality, premium service every time.