Correct data is essential to developing accurate estimates of value; therefore, field inspections conducted by our appraisers play a very important part in the process.

Each Galveston CAD appraiser works from his or her own personal vehicle. The appraiser carries an identification badge with his or her picture, name, and unique appraiser number.

Below are the various field projects and detailed descriptions of the type of project we may be performing in your neighborhood.

To verify that the individual working in your neighborhood is actually an appraiser with GALVESTON CAD, please feel free to contact our office at (409)935-1980.

New Construction

Our appraisers inspect neighborhoods and individual properties to observe changes in neighborhood condition, trends and property characteristics. By law, we must continually update property characteristic data to reflect changes brought about by new construction, new parcels, remodeling, demolition, and other changes. 

We receive information on the location of building activity through building permits from the cities and county, fire reports, data mailers, and other sources. During a new construction inspection project, an appraiser will inspect only those with identified changes. Depending on the volume of construction activity, you might see one or more appraisers working in your area.

Sales Verification

The appraiser physically inspects properties that have sold, typically within the last 18 months. The purpose of the inspection is to verify the accuracy of our data about the sales transaction information and the characteristics of the property. The appraiser usually does not visit every home on the street, only those with recent sales activity. Depending on the volume of sales activity, you might see an appraiser working in your area for the entire day or for just a short time.

Periodic Reinspection

Whether or not it sells or has new construction, we try to inspect every residential property in Galveston County once every four to six years. The two projects below are related to this periodic inspection. During a reinspection project it is likely you will see an appraiser in your neighborhood for several days.

1. Driving Review:

A driving review is a general inspection of property to ensure that our property records are accurate. The appraiser’s responsibility is to verify the accuracy of property data for every property within a neighborhood. The appraiser generally does so from the appraiser’s vehicle. This project is carried out in conjunction with the field reinspection project described below. If the appraiser determines that a property needs a closer look during the driving review, the appraiser will assign it to the field reinspection project for an on-site inspection.

2. Field Reinspection:

The appraiser will conduct an on-site inspection of properties in the neighborhood to verify characteristics and neighborhood condition. It is typical for the appraiser to visit most, if not all, of the properties on a street.

Limitations on Increasing Property Values on Your Home

Prices of new and used homes in Galveston County have increased substantially in recent years. In order to prevent sharp increases in home property taxes from year to year, Texas voters in 1997 approved a constitutional amendment, which became effective January 1, 1998, to limit increases in the taxable value of a qualified residence homestead. 

To qualify, property must be your residence homestead, and you must have received a homestead exemption in your name in both the current and previous years.

Under this law, the value for tax purposes (appraised value) of a qualified residence homestead will be the LESSER of:

  • the market value (what the property would sell for on the open market); or
  • the preceding year’s appraised value
  • + 10%
  • + the value of any improvements added since the last re-appraisal.

For more information about Homestead Caps please visit our Public Data page under videos. 

How the Galveston Central Appraisal District Appraises Residential Property

The following presentation is provided to educate Galveston County residential property owners about the Analysis & Valuation Phase of the appraisal year. Information will be provided about the mass appraisal process utilized to value residential property. The application of ratio studies and other common statistical measures used throughout the valuation process will also be explained. An overview of market areas/ neighborhoods and their importance on value will also be covered, followed by a brief demonstration of the method applied during the mass appraisal process.

Mass appraisal is the systematic appraisal of groups of properties as of a given date using standardized procedures and statistical testing. Appraisal districts use of mass appraisal evolved out of the need to appraise many properties efficiently and equitably each year. The Texas Property Tax Code requires appraisal districts to maintain property records and assign yearly value to all property within each county. Mass appraisal provides appraisal districts the ability to accomplish such a large task in a proficient and unbiased manner.

The primary tool used to measure mass appraisal performance is the ratio study. This analysis compares appraised values to market values. Market values are usually represented by individual transactions or sales prices. Each year, the appraisal district must research sales it is able to acquire and apply them in the mass appraisal process to value all property regardless of whether it sold or not. The ratios in a ratio study are referred to as appraisal-to-sale ratios. They are formed by dividing the district’s calculated appraised values by the sale price of the same property. For example, a property valued by the appraisal district for $100,000 that sold for $105,000 has a ratio of 0.95 or 95 percent. Appraisal districts are expected to achieve a median ratio level of 100 percent of market value.

Texas Property Tax Code section 5.10 also directs the state comptroller to conduct similar biannual ratio studies to ensure appraisal districts are achieving ratios within required parameters. After the July 25th value certification date for appraisal districts, the comptroller’s office collects all of that tax year’s sale and appraisal data from each district. The Property Tax Assistance Division then begins its own ratio study process to re-check values established by each appraisal district as compared to the sales collected. The Property Tax Assistance Division is required to report if districts are appraising by the
State required level and uniformity. Results of the biannual studies may be viewed on the comptroller’s website:

Ratio studies performed by appraisal districts and the comptroller measure two primary aspects of mass appraisal accuracy: level and uniformity. The level of appraisal shows whether the district has appraised typical properties at 100 percent of the legally required level. In Texas, that is the market value or sale price. The uniformity of appraisal indicates how much the percentage of market value varies from the required level within groups of properties. Two of the most common statistical measures used to test appraisal level and uniformity in the mass appraisal process are the median and the coefficient of

he median is the midpoint, or middle ratio, when the ratios are arrayed in an ascending or descending order. The median separates the ratios into two equal groups, so half of the array is higher than the median and the other half is lower. The median is also the base from which the coefficient of dispersion is calculated. The COD measures how tightly or loosely the individual sample ratios are clustered around the median. A high COD indicates high variation which means few ratios are close to the median and there is low appraisal uniformity. A low COD indicates that there is low variation and the ratios are
clustered tightly around the median which translates to high appraisal uniformity. A COD on residential properties below 20.0 is acceptable according to IAAO Standards. As illustrated, the COD is calculated by first finding out the absolute deviation from the median each ratio has. Then, the Average Absolute deviation of the ratio group is determined, divided by the median, and then multiplied by 100 to convert the ratio to a percentage.

Accurate identification of market areas is a vital component in the development and utilization of an efficient and accurate mass appraisal system. A variety of forces influences property values. It is the appraiser’s responsibility to identify groups of property that experience similar influences and define them as market areas. In Galveston County market areas are delineated primarily on school district boundary lines. Being said school districts may be parsed into smaller market areas based on
influencing factors. Within these market areas properties are further delineated into neighborhoods. Research on value influences in Galveston County has resulted in neighborhood delineation by geographic location, age or quality of a structure, by various builders or model types, or other major influencing factors. Appraisers assign numerical descriptors known as neighborhood codes to all property within identified areas of similar value influences. As illustrated, a subdivision may contain various neighborhood codes as a result of the varying identified value influences. The assigning of neighborhood codes allows appraisers to efficiently and uniformly appraise all property in the defined group by the available known sales information.

Once the available sale and property information is displayed, an appraiser may begin mass appraisal through a process of applying market modifiers to the properties in each defined neighborhood code. Market modifiers are also referred to as neighborhood factors. Factors are used to trend the components of a property’s improvement value up or down as a result of the sales provided. A property record card illustrates how improvement components, as identified through prior property inspection, make up the total improvement value. The neighborhood factor is the final valuation step used each year to modify the improvement value up or down so that when added to the land value, a final value is calculated that produces an acceptable appraisal to sale ratio as previously described.

Table 2 shows that the prior year neighborhood factor of 150 is producing appraised values lower than the known sale prices. The ratio column is indicating the majority of the sales ratios are below the state required level. Further confirmation is provided by the median ratio of 92.84. The low COD of 0.61 reveals that there is a high level of uniformity in the valuation which means the ratios are closely grouped around the median. An appraiser will begin to adjust the new neighborhood factor to bring the median ratio up closer to the state required level. In this case, a new neighborhood factor of 159 produces an acceptable median ratio of 97.56 and a COD of 0.60 as shown in Table 3.

The Appraisal District is responsible for appraising properties at market value as of January 1st of each tax year. To accomplish this task the District collects sales information from transactions that occurred during the twelve months preceding the appraisal date. It has been the District’s policy for many years to consider foreclosure or distressed transactions. These transactions are analyzed to determine if they are representative of or affecting the market in each neighborhood. This process is repeated annually for approximately 3,000 neighborhood codes to reflect the changing real estate market and value approximately 196,000 residential properties in the county.