The main purpose of an as-built survey is to ensure that construction is going as planned. Survey measurements made while construction is in progress to control:
County agencies, city agencies and banks as well as mortgage companies may request this type of survey. Banks and mortgage companies want a professional to certify that the house they are backing with a mortgage is in the clear in regard to zoning setbacks, building setbacks and existing easements.
Monitoring is done when doing work against adjoining buildings or if you suspect nearby construction is causing a structure to move. NYLS provides Optical Monitoring solutions for various applications. It is usually necessary if a site inspector or project engineer requests a copy on site.