Property Assessment: Building Attributes & Use Analysis

Property Assessment: Building Attributes & Use Analysis

Introduction

This chapter delves into the critical aspects of property assessment focusing on building attributes and use analysis. A thorough understanding of these elements is paramount for accurate real estate valuation and informed decision-making. We will explore the scientific principles underpinning building construction, materials, and functionality, as well as the market and regulatory factors influencing property use.

1. Building Description: Unveiling the Property’s Physical Characteristics

The building description forms the foundation for comparing the subject property to comparable properties and determining its highest and best use. It requires objective and analytical observation, focusing on components that influence value.

• 1.1 Elements of a Building Description

  A comprehensive building description considers the following in sequence:

  1. The existing building’s type of use.
  2. The codes and regulations affecting that use.
  3. Building size, plan, and construction details.

  4. Details of the building’s exterior and interior and its equipment and mechanical systems, including original construction and subsequent improvements.
     * 1.2 Construction Materials and Techniques
     Typical construction materials and techniques used in a region change over time for the following reasons:

  5. New building technologies evolve.

  6. The prices of materials fluctuate significantly.
  7. Rising or falling energy prices make a particular building material or construction technique more desirable.
  8. The dictates of fashion affect the demand for a certain building material or feature.

2. Scientific Principles in Building Assessment

Understanding the scientific principles governing building construction and performance is crucial for identifying potential issues and accurately assessing value.

• 2.1 Structural Mechanics and Load-Bearing Capacity

  • Buildings are designed to withstand various loads, including dead loads (weight of the structure itself), live loads (occupants, furniture), wind loads, and seismic loads.

  • Stress and Strain: The relationship between applied force (stress, σ) and deformation (strain, ε) is fundamental. For elastic materials, Hooke’s Law applies:

    σ = Eε

    where E is the Young’s modulus (a material property representing stiffness).
    * Material Properties: Different materials possess unique properties affecting structural performance:
    * Tensile Strength: Resistance to pulling forces.
    * Compressive Strength: Resistance to crushing forces.
    * Shear Strength: Resistance to forces acting parallel to a surface.
    * Flexural Strength: Resistance to bending forces.
    * Practical Application: Assessing a building for signs of structural stress, such as cracks in walls or sagging floors, requires understanding these principles.
    * Experiment: Non-destructive testing (NDT) methods, like ultrasonic testing, can be used to assess the internal integrity of concrete or steel without causing damage. This is relevant for large commercial properties where hidden defects can cause significant risks.

• 2.2 Building Envelope and Energy Efficiency

  • The building envelope (walls, roof, windows, doors) regulates heat transfer, moisture infiltration, and air leakage.

  • Heat Transfer: Heat flows through the building envelope via conduction, convection, and radiation.

    • Conduction: Heat transfer through a material, governed by Fourier’s Law:

      Q = -kA(dT/dx)

      where Q is the heat flow rate, k is the thermal conductivity, A is the area, and dT/dx is the temperature gradient.
      * Convection: Heat transfer due to fluid movement (air or water).
      * Radiation: Heat transfer via electromagnetic waves.
      * R-Value and U-Value: These metrics quantify thermal resistance and transmittance, respectively. Higher R-values and lower U-values indicate better insulation.
      * Air Leakage: Uncontrolled air infiltration increases energy consumption and can lead to moisture problems.
      * Practical Application: Identifying areas of poor insulation, air leaks, or thermal bridging is crucial for improving energy efficiency and reducing operating costs.
      * Experiment: A blower door test measures the air tightness of a building by depressurizing it with a fan and measuring the air flow required to maintain a constant pressure difference. This determines the Air Changes per Hour (ACH) and identifies areas of significant leakage.
      * 2.3 Building Systems: HVAC, Electrical, Plumbing

  • HVAC (Heating, Ventilation, and Air Conditioning): Maintains comfortable indoor temperature and air quality. Thermodynamics and fluid dynamics govern the operation of these systems.

  • Electrical Systems: Delivers power throughout the building. Ohm’s Law (V=IR) and power calculations (P=VI) are fundamental.
  • Plumbing Systems: Supplies potable water and removes wastewater. Principles of fluid mechanics govern flow rates and pressure.
  • Practical Application: Assessing the condition, efficiency, and capacity of these systems is vital for ensuring functionality and safety.
  • Experiment: An infrared thermography scan can identify hotspots in electrical panels or leaks in plumbing systems, indicating potential problems.

3. Use Classification and Regulatory Considerations

The permitted use of a property is governed by zoning regulations and building codes.

• 3.1 Zoning Regulations

  • Zoning regulations establish the permitted uses of real estate.
  • Existing and potential land uses must be checked against zoning regulations to determine if they are conforming or nonconforming uses.
  • When the present use does not conform to current zoning regulations, an appraiser should consider how this fact might affect property value.

• 3.2 Building Codes and Ordinances

  • In addition to any use restrictions imposed by zoning, the planning and construction of buildings are restricted by various laws, codes, and regulations enacted at all levels of government to protect the health, safety, and welfare of the public.
  • Municipal building codes establish requirements for the construction and occupancy of buildings and may contain specifications for building materials, methods of construction, and mechanical systems. These codes also establish standards of performance and address considerations such as structural strength, fire resistance, energy and water usage, and adequate light and ventilation.

4. Size and Measurement Standards

Accurate measurement of building size is crucial for valuation.

• 4.1 Measurement Techniques

  • The methods and techniques used to calculate building size vary regionally, differ among property types, and may reflect biases that significantly affect opinions of value.
  • The relevant type of measurement varies depending on the property type and, more specifically, how market participants treat the measurement of that property type. For example, net rentable area is commonly used for office buildings, while gross living area is commonly used for one-unit residential properties.
  • Distinctions between gross building area, gross living area, usable area, and rentable or leasable area need to be clearly understood.

  • 4.2 Standards for Measurement

  • Standards for measuring residential property have been developed by several federal agencies, including the FHA, the VA, Fannie Mae, and Freddie Mac

  • Another widely accepted measurement standard for residential properties is Square Footage— Method for Calculating: ANSI Z765-2002, developed by the National Association of Home Builders (NAHB) Research Center with the American National Standards Institute (ANSI).
  • The Building Owners and Managers Association International (BOMA) has established a method for measuring office building floor area.

5. Green and High-Performance Buildings

The increasing prevalence of green buildings necessitates specific considerations in property assessment.

• 5.1 Green Building Principles

  • Green building encompasses environmentally responsible and resource-efficient practices throughout a building’s lifecycle.
  • Key aspects include energy efficiency, water conservation, sustainable materials, and indoor environmental quality.

  • 5.2 Benchmarking

  • Buildings built to a green standard should exceed the local building code and should have a paper trail to provide the details of the building standard.

  • Benchmarking is the practice of comparing the measured performance of a device, process, facility, or organization to itself, its peers, or established norms, with the goal of informing and motivating performance improvement.

  • 5.3 Market Perception

  • Market Perceptions of Green Features- nearly 70% of residential and commercial realtors indicated that the listing of energy-efficient building components was somewhat or very valuable. A majority of home buyers were reported to be interested in sustainability, and solar panels increased the perceived value of homes. Properties with green certifications experienced typical marketing times.

6. Conclusion

A comprehensive property assessment requires a deep understanding of building attributes and use analysis. By applying scientific principles, adhering to measurement standards, and considering regulatory factors, appraisers can provide accurate and reliable valuations that reflect the true worth of a property.