Survey tolerances

Futbalfantic

Well-Known Member
Joined
Aug 5, 2006
Location
Charlotte
What is the tolerance on a land survey. Been setting fence posts on my property and that got me wondering. If I have 10 surveyors out without any or only one marker present. How much variance will occur?
 
I was told by my surveyor that if they have markers on 2-3 corners, they can get down to a very tight tolerance, but working from one corner it could vary wildly. Also, it all depends on how exact was the survey when it was taken? Was it done in the 1800s with rods and chains, or 10 years ago with GPS. If the original survey was off by 1-2 degrees at each corner, that would add up to a huge variation on a long property line, and even the best surveyor cant fix that.
 
Generally, a class A survey requires a 1:10,000 closure. So you you can have an error of closure of 1' for 10,000' traversed in a closed loop. When it comes to lost or obliterated corners, reestablishing the property line is somewhat methodical, but also includes some judgment by the surveyor. By survey law, the order of operations for reestablishing a property corner is 1. Monuments, they always control as long as they are within reasonable tolerances. 2. Distance. 3. Course (bearing). 4. Prima fascie evidence. That being said, property is subdivided in two ways in NC. By subdivision plat or deed with metes and bounds description. In platted subdivisions, we survey to the next property or two, then prorate distances. By deed, there are junior and senior rights. The out parcel always gets what the deed calls for, and the parent tract is left with what is left regardless. Two or ten good surveyors should come up with fairly the same reestablishment of a property corner. As a surveyor, our duty is to promote and protect the welfare of the public, so property lines should be reestablished the same, regardless of who hired you.
 
Generally, a class A survey requires a 1:10,000 closure. So you you can have an error of closure of 1' for 10,000' traversed in a closed loop. When it comes to lost or obliterated corners, reestablishing the property line is somewhat methodical, but also includes some judgment by the surveyor. By survey law, the order of operations for reestablishing a property corner is 1. Monuments, they always control as long as they are within reasonable tolerances. 2. Distance. 3. Course (bearing). 4. Prima fascie evidence. That being said, property is subdivided in two ways in NC. By subdivision plat or deed with metes and bounds description. In platted subdivisions, we survey to the next property or two, then prorate distances. By deed, there are junior and senior rights. The out parcel always gets what the deed calls for, and the parent tract is left with what is left regardless. Two or ten good surveyors should come up with fairly the same reestablishment of a property corner. As a surveyor, our duty is to promote and protect the welfare of the public, so property lines should be reestablished the same, regardless of who hired you.

What’s that “reasonable tolerance?” On say a 100x100 subdivision lot. Is it that 1’:10,000’ (which to my dumb self is 1/8” tolerance). Seems extremely small Deviation
 
What’s that “reasonable tolerance?” On say a 100x100 subdivision lot. Is it that 1’:10,000’ (which to my dumb self is 1/8” tolerance). Seems extremely small Deviation
Correct, 0.01' allowable error on a 100' lot.1/8" is about a hundredth. That's for as-surveyed conditions, meaning the survey loop needs to close within that acceptable error, 1:10,000. As I said, monuments control, so if existing monuments (rebar, pipe, nail, etc.) is within a few tenths it's generally acceptable. If more, I'll usually locate the nearest property corner and make sure everybody has what they're supposed to have.
 
Rebars and pipes near trees can get pushed around/moved when trees or roots grow. I've seen many corners that were disturbed or just moved by neighbors. Most of the time a adjoiner built a fence w/o a survey and then tried to make the fence look like it was on their property and I've seen fences taken down and moved.
 
Rebars and pipes near trees can get pushed around/moved when trees or roots grow. I've seen many corners that were disturbed or just moved by neighbors. Most of the time a adjoiner built a fence w/o a survey and then tried to make the fence look like it was on their property and I've seen fences taken down and moved.

speaking of, one of my corners resides in the loving embrace of the base/roots of an oak....
 
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