Metes and Bounds: Describing Property Boundaries

Chapter 4: Metes and Bounds: Describing Property Boundaries

I. Introduction to Legal Descriptions

• Informal descriptions (e.g., street addresses, common names) are insufficient for legally defining property boundaries.
• A legal description uniquely identifies a property’s exact boundaries.
• Appraisers should be able to recognize whether the description meets the local standards, and should also be able to identify the real estate that is described in the legal description.
• Three primary methods of legal description are used in the United States:
  1. Metes and Bounds System
  2. Rectangular (U.S. Government) Survey System
  3. Lot, Block, and Tract System

II. Metes and Bounds System: Scientific Principles and Practical Application

The metes and bounds system defines property by describing its perimeter, using distances❓ (metes) and directions (bounds) from known reference points. It’s the oldest and often most complex method.

A. Fundamental Components

1. Reference Points (Monuments)

   • Definition: Identifiable, fixed positions used as starting points for measurements.
   • Types:
     • Artificial Monuments: Man-made markers (e.g., metal stakes, concrete monuments).
     • Natural Monuments: Natural features (e.g., trees, rocks, rivers).
   • Point of Beginning (POB): The initial reference point where the description starts and ends.
   • True Point of Beginning (TPOB): The specific location on the actual property boundary where the description of the property’s perimeter begins. The POB and TPOB may or may not coincide.

B. Courses and Distances (Metes)

1. Direction (Course)

   • Definition: The angular direction from a reference direction (North or South).
   • Units of Measurement: Degrees (°), Minutes (‘), Seconds (“).
     • 1 degree (1°) = 1/360th of a circle
     • 1 minute (1’) = 1/60th of a degree
     • 1 second (1”) = 1/60th of a minute = 1/3600th of a degree

   • Cardinal Directions: North (N), South (S), East (E), West (W)

   • Quadrant System: Courses are defined relative to the North or South direction and an East or West offset. For example:

     • Northeast (NE): Angle measured East from North (e.g., N 45° E).
     • Northwest (NW): Angle measured West from North (e.g., N 30° W).
     • Southeast (SE): Angle measured East from South (e.g., S 60° E).
     • Southwest (SW): Angle measured West from South (e.g., S 15° W).

2. Distance

   • Definition: The length of a boundary line between two points.
   • Units of Measurement: Feet, meters, chains, rods, or other units as locally defined.

C. Mathematical Representation of Courses and Distances

The course and distance can be represented as a vector. Let d be the distance and θ be the angle (course) from North or South. The change in Northing (ΔN) and Easting (ΔE) can be calculated as follows:

If θ is measured from North:

• ΔN = d * cos(θ)
• ΔE = d * sin(θ)

If θ is measured from South:

• ΔN = - d * cos(θ) (for Southeast and Southwest quadrants)

• ΔN = d * cos(θ) (for Northeast and Northwest quadrants)

• ΔE = d * sin(θ) (positive for Southeast and Northeast quadrants, negative for Southwest and Northwest quadrants)

This allows transforming each course and distance into coordinate changes which can be accumulated to verify closure.

D. Closure and Error of Closure

• Closure: The requirement that the metes and bounds description returns exactly to the point of beginning (POB).

• Error of Closure: In reality, due to measurement inaccuracies, a perfect closure is rarely achieved. The error of closure is the distance between the calculated ending point and the actual POB. It’s an indication of the accuracy of the survey.

• Linear Error of Closure = √((ΣΔE)^2 + (ΣΔN)^2) where ΣΔE and ΣΔN are the sums of the Easting and Northing differences for the entire description.

• Relative Error of Closure: The ratio of the linear error of closure to the total perimeter distance. A higher ratio indicates lower accuracy.

  • Relative Error = (Linear Error of Closure) / (Total Perimeter Distance)
  • Expressed as a fraction (e.g., 1/10,000). A relative error of 1/10,000 means that for every 10,000 units of distance surveyed, there is a potential error of 1 unit.

E. Practical Applications and Related “Experiments”

1. Simulating a Survey:

   • Description: Enter a metes and bounds description into a computer-aided drafting (CAD) or geographic information system (GIS) software. The software will draw the property boundary based on the input data.
   • Purpose: Visually verify the shape and closure of the property. Identify potential errors in the description.
   • Software: AutoCAD, ArcGIS, QGIS

2. Calculating Area:

   • Description: Using the courses and distances, calculate the area enclosed by the metes and bounds description. Several methods exist, including:
     • Coordinate Geometry (COGO): Calculates the area based on the coordinates of each point. Requires converting all courses and distances to coordinate pairs.
     • Trapezoidal Rule: Approximates the area by dividing the parcel into trapezoids and summing their areas. Less precise than COGO.

   *Formula for area using coordinates:
   Area = 0.5 * | Σ (Xi * Yi+1 - Xi+1 * Yi)| where the sum is from i = 1 to n, and Xn+1 = X1, Yn+1 = Y1.

   • Purpose: Determine the size of the property. Check for inconsistencies between the calculated area and the stated area in the deed.

3. Field Verification (Simplified):

   • Description: Using a measuring tape, compass, or GPS device, attempt to locate and verify a few key points (monuments) and boundary lines of a simplified metes and bounds description in the field.
   • Purpose: Gain a better understanding of how metes and bounds descriptions translate to physical space. Identify potential discrepancies between the description and the actual property. (Note: This should not be considered a professional survey.)

F. Modern Surveying Techniques

1. Laser Transits:

   • Improve accuracy in measuring angles and distances compared to traditional surveying methods.

2. Established Benchmarks:

   • Survey markers set in heavy concrete monuments provide reliable reference points.

3. Satellite Technology (GPS/GNSS):

   • Used to precisely locate points and establish datums for surveying.

III. Metes and Bounds in Appraisals

• Complex and lengthy descriptions increase the risk of errors during transcription.
• Photocopying from original documents is a common practice to minimize transcription errors.
• Appraisers can use software to calculate the parcel area and simulate a survey to check for closure.
• Metes and bounds is particularly useful for describing irregular or oddly shaped parcels where the Rectangular Survey System is not suitable.

IV. Transition to Rectangular Survey System

• The next section will cover the Rectangular (U.S. Government) Survey System as an alternative method of legal description.