When closing on the surveyor’s own work in new surveys, the minimum accuracy is 1:7,500 or 0.02 metres. When closing on work performed by other surveyors, the minimum accuracy is 1:5,000 or 0.02 metres.
 

What does this mean?

For example, two measurement that are difference by 0.1 metres over a distance of 750 metres are considered to close to 1:7,500. Because a normal urban residential lot is much smaller than 750 metres, measurements shown on a plan that are within 0.02 metres of another measurement are considered to be accurate.
 
Even though technology is better than it was just a few years ago, one cannot assume that a modern-day survey is more accurate or more correct than one done years earlier. The land surveyor is always trying to re-establish the boundary set by the original land surveyor and not just measure distances more accurately.
 
Landowners should not use the distances shown on a survey and a tape measure or a ruler to try to establish boundaries. There is a high degree of likelihood that landowners will misinterpret the distances shown on the plan or make a measurement error.
 
When a landowner tries to repeat a measurement made by a land surveyor, they will often get a different result because the land surveyor is measuring from the property line to, for example, the foundation of the house while the landowner may be measuring from the corner of the house to the fence which may or may not be on the property line.
 
It is also difficult for a landowner to duplicate a measurement made by a land surveyor because a measurement taken by a landowner may not be perfectly horizontal and the dimension shown on the plan to the boundary may not be along the extension of the wall of the house.
 
If a landowner needs to know the location of their boundary, please do not use a real property report to try to determine it yourself. Retain the services of a professional land surveyor to mark the boundary on the ground and/or provide a sketch for that purpose. The real property report is intended to show where improvements are located relative to a boundary for a real estate transaction but is not intended to be used to locate a boundary.