Note: this guideline is issued by the Surveyor-General under section 7(1)(ga) of the Cadastral Survey Act 2002 about the Rules for Cadastral Survey 2010 and is not legally binding.

The following information relates to rule 3.2 and the accuracy classes that apply to boundaries and boundary points.

Historically, classes of accuracy were assigned to parcels and not boundaries.  The assignment of some classes of survey was made on parcel size (that is, greater or less than 4 ha) which could result in anomalies.  For example a small piece of land being taken for road in a rural environment required the more stringent urban class of accuracy.  This is no longer applicable.

Classes of accuracy are now assigned to boundaries and boundary points and the criterion for increasing the accuracy class of survey in a rural area is now based on specific land use (intensive commercial, industrial, or residential purposes).

Hierarchy of boundary accuracy

The Rules provide four classes of accuracy which apply only to boundaries and boundary points. The four classes are defined in rule 3.2 as:

  • class A (urban and the most accurate), 
  • class B (rural and not as accurate as class A), 
  • class C (used in specified rural circumstances where a less accurate boundary is acceptable), and 
  • class D (used in exceptional rural circumstances where the existing boundary accuracy is unknown or unable to be determined and it is appropriate to permit these inaccuracies to remain).

Accuracy class applies to boundary, not parcel

A class of accuracy applies to a boundary and its associated boundary points rather than to a parcel [r 3.2]. A parcel can be made up of a mixture of classes of boundaries. For example, see figure 1 below.

When class A or class B boundary accuracy applies

Class A is to be applied in an urban area and also in a non-urban situation where the boundaries and boundary points are associated with a parcel intended for intensive commercial, industrial, or residential purposes [r 3.2.1(b)].

Where there could be doubt as to whether a boundary should be class A or B, the surveyor will need to decide and, if class B is chosen, provide supporting information in the survey report to support the decision.

Any boundaries or boundary points may be surveyed to class A accuracy if the surveyor chooses to do so.

Boundaries 'defined by survey' must be class A or class B unless a lower accuracy class is approved by the Surveyor-General [r 3.2.5(b)].

When class B or class C boundary accuracy applies

Class C accuracy tolerances are not to be applied without first testing to determine if class B accuracy tolerances are applicable [r 3.2.3(a)(iii)].

Exceptions to the above are where: the title will remain limited as to parcels or an interim title [r 3.2.3(a)(iv)]; or the boundary is a water or irregular boundary [r 3.2.3(a)(v)]; or the boundary is for a covenant [r 16].

If a boundary meets either class C or class D criteria [r 3.2.3 and r 3.2.4], then either of the classes may be used.

If the boundary does not meet class C or D criteria, it must be resurveyed to class B standards [r 6.2(a)(vi)].

When class C or class D boundary accuracy applies

In specified circumstances where the accuracies of class B cannot be met, the use of class C [r 3.2.3] or class D [r 3.2.4] is permitted.  These classes relate only to existing boundaries and boundary points except where a specific dispensation has been approved by the Surveyor-General [r 3.2.3(c)].

The use of class C is also permitted for new boundaries of covenants under rule 16 (refer to Alternative requirements for covenant parcels (rule 16)). 

figure describing boundary classes that comply with rule 3.2
Figure 1: Boundary classes that comply with rule 3.2

Class of boundary vector

Where a boundary's end points are of different classes, the lower class of accuracy applies between these end points [r 3.3.1(b) and r 3.7].

Figure 2: Accuracy class of boundary vector

Class of boundary point

The accuracy class of a boundary point is the highest accuracy class of the boundaries connected to that point [r 3.2.5(a)]. 

Figure 3: Accuracy class of boundary point

Boundary accuracy where non-primary boundary coincides with class C or D primary parcel

Where a new or existing non-primary parcel boundary coincides or intersects with a new or existing class C primary parcel boundary, the non-primary parcel boundary may also be class C [r 3.2.3(b)].  The same applies for a class D primary parcel boundary [r 3.2.4(b)].

Note that if the accuracy of the primary parcel boundaries is later upgraded upon resurvey, a non-primary parcel boundary that coincides with a primary parcel boundary may also need to be upgraded to a higher accuracy [r 3.3.1].

Also refer to class of boundary point above.

Figure 4: Boundary intersects with class D boundary
Last Updated: 2 May 2017
Authority: Surveyor-General - Section 7(1)(ga) of the Cadastral Survey Act 2002
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