Property Value Theory - Some useful terminology and observations on urban property values

I've been developing a theory and some terminology that I find very helpful in explaining urbanism to developers, city officials, and others who "don't get it." Here's the gist of it, at the end you can find a link to my blog if you'd like to read a bit more. I hope you all enjoy!

- Background -

First a bit about me and how I've come up with this. My name is Andrew Burleson, and I currently work as a real estate consultant in Houston. I have a undergrad degree in Environmental Design and a Master's in Land and Real Estate Development. I'm an ardent advocate for good urbanism, and I've invested a lot of time studying it.

Many of the people I interact with don't have a good idea in their heads of what urbanism is or why it matters. I've found that it helps a lot to connect form and design related concepts to property values and financial figures. This helps people to see the impact design has on daily life beyond aesthetics.

As I've talked with people about these things I've slowly developed a theory that connects a lot of separate ideas and gives me a way to describe how they relate. For lack of a more intriguing title, I call this my Property Value Theory.

If you're interested in reading a more “thorough” version of this same write-up with more detailed examples, try reading the Introduction to Property Value Theory on my blog.

Here the short version:

- Theory: -

Two kinds of land

From an economic point of view there are two kinds of land: rural, and urban. The difference between the two is the way in which they are used, which determines the way in which they are valued.

Rural land is valued for its resource-productivity. This land is valued based on what it produces (food, water, minerals, etc) and the market value of those resources.

Urban land is valued for its people-productivity. This land is valued based on the activities it houses, and the market value of those activities.

This means that at a fundamental level all non-rural land becomes valuable based on how effectively it attracts human activity. For instance: Houses are valuable if people want to live in them. Bigger residential structures are more valuable as more people live in them. The more people want to live in a specific spot, the more valuable it will be. Unit value is a function of the difference between how many people would like to live in a place (demand) versus how many residences are available in that place (supply). Thus, the mansions in places like Beverly Hills command enormous price premiums.

**an aside: Natural land (undeveloped) produces resources that we think of as "free," such as clean air and water. These resources are fundamental to Human life and extremely valuable, thus this theory helps provide economic justification for higher dollar value for pristine land.

For more on this aspect of the theory, you can read: Property Value Theory, Part 1: People-Productivity

Structures, Interfaces, and Conduits

*This section is really the crux of my theory, so if you find it interesting you'd probably enjoy the more complete write up on the blog.*

Now, we all can see that property values can vary significantly from lot to lot or block to block, even when the base level desirability of a location should be the same for these individual properties. The reasons for these micro-level property value differences is the presence of manipulators.

There are three major manipulators: structures, interfaces, and conduits

Structures are the buildings on a property. Structures are used to meet the specific needs of an end user.

• The relationship between structures ("improvements") and property values is already pretty well understood, but here's a quick example: when comparing between two similar homes each individual buyer will have different preferences, and the details of the structure (how many bedrooms, bathrooms, the quality of the flooring etc. etc.) will influence each individual buyer to make a final decision.

Interfaces are places for interaction. They are public spaces and the public areas of private property. Interfaces are the connections between structures and the outside world.

• The relationship of interfaces and property values is not widely understood, but it's critical. Interfaces are the strongest attractant, and therefore the manipulator most able to create property value. The simplest example is the way a new neighborhood, if all other factors were stable, would be expected to gain in value over time. Why? Because trees are great additions to interfaces, and the bigger trees are the more value they add. As the trees grow and provide shade and structure to a neighborhood street, the properties along it should gain value. This is because the quality of their interface would be improving.

Conduits are infrastructure links not used directly by people. They are rail lines, freeways, phone lines and sewer systems.

• The relationship between conduits and property values is somewhat widely understood. Generally, conduits are what we think of when we think of infrastructure. The key to understanding these is to understand that "machine" spaces (like subway lines) are strictly conduits, whereas "shared" spaces like streets and boulevards contain both a conduit and an interface. A great multiway boulevard would contain both an efficient transportation conduit in its center and a high-quality interface along it sides.

Structures, Interfaces, and Conduits can be either attractant or repellent. Trees and flower gardens are attractant. Razor-wire fences are repellent (on purpose).

Manipulator Attributes:

All manipulators have two critical attributes: radiance and displacement. The biggest most important difference is that radiance is the general impact on all end users, and displacement is the impact on a specific group of end users

Radiance is the degree of influence and area of influence a manipulator has on surrounding properties.

• Structures have very low radiance, they will often have little or no impact on surrounding properties at all.
• Interfaces are highly radiant, they have a significant impact on the values of surrounding properties, and this value has a tendency to spread.
• Conduits have an inverse logarithm of radiance. They have a very high impact directly near them, and a slight impact on properties very far away.

Displacement is the degree to which a manipulator attracts or repels a specific user-group. These are directly tied to specific elements of a structure, interface, or conduit and form a spectrum from VITAL to NOXIOUS.

• NOXIOUS elements displace specific users away from a site by repelling them. For instance, the noise generated by a freeway is noxious to residential users, because they need to be able to sleep at night.
• VITAL elements can displace specific users by “outbidding” them. Thus, as an area becomes more and more full of people you would expect to see certain uses get 'pushed out' by others, such as residences being replaced with shops.

The biggest most important difference between the two manipulator attributes is that radiance is the general impact on all end users, and displacement is the impact on a specific group of end users. Also, displacement impact can be mitigated, whereas radiance cannot.

For more on this, you can read: Property Value Theory, Part 2: Interfaces and Conduits

The Value for New Urbanists

New Urbanism is mainly about building strong communities that are supported by strong interfaces. This is often seen as a subjective art, but we're fortunate that many leading thinkers have invested significant time and energy in observing and reporting what works and what doesn't when it comes to urban space.

In Part 3 of my look at Property Value Theory, I looked at some of the lessons from Jane Jacobs and William Whyte, and combined those together into a list of characteristics for attractant places. These are: mixed-use; small blocks; sitting space; sun and shade; motion, color and texture; sound; food; niche facilities; layers and vistas.

If you'd like to read more about that, try: Property Value Theory, Part 3: Places that Attract People.

- - - - -

Now, this is my own theory of how property values are created. It's a living, breathing, work-in-progress, and I'd really love to discuss it with anyone who finds it interesting. The idea probably needs a better name than “Andrew's Property Value Theory,” so I'd welcome any suggestions.

If you find this idea helpful I'd love for you to use it, but if you don't mind I'd appreciate your attribution of the idea, as well as a link to my blog at http://www.neohouston.com.

Speaking of attribution: Where an idea that inspired my thinking came directly from another source I've attempted to give credit. I think I've covered everything, but I don't want to be seen as claiming credit for any portion of the idea that came from somewhere else. That said, I read a lot and have been influenced by many people, and if you read this and think: "that part is exactly the same as what _______ said in his book," and I haven't given sufficient credit, please let me know.

Also, this is my first post on CNU Salons, so I'm a bit nervous about whether I've managed to present this in a way that's kosher with the community here. If there's anything I need to be aware of, please let me know.

Thanks for reading, and I appreciate your feedback!