From SimCity Wiki
The way you lay your zones out largely determines the success and size of your city. Great care must be taken to ensure that zones are of proper size and close enough to beneficial buildings.
I have found that once you have hit the highest stage of skyscrapers, most buildings will want a 4x2, 4x3 or 4x4 base to build on. However, when starting out, there are no buildings that take this size lot. A practical way to get started while still keeping in mind later expansion is to lay out roads so there is room for a 4x? lot, and then zone medium 2x2 lots down either side of the roads. A 4x4 square is fine, as is 4x6 or 4x8. Later in the game when demand for residential or commercial is higher, you can rezone these areas as heavy density. Buildings with a 4x? footprint will grow on the rezoned areas, even though they are currently 2x2/2x3 lots.
No matter what the zone, if there is too much traffic, property values will fall. In extreme cases, buildings will be abandoned due to commute time. While commercial likes high traffic situations, it doesn't like exessive traffic noise. Residential doesn't care about volume, but hates noise, so keep things running smooth. Read more about proper grid layouts on the Traffic Management page.
Affecting Zone Placement
Simcity 4, by default, will auto-determine the orientation of your zones, as well as the street connections through them. The game will automatically size the individual cells in a perspective zone based on the severity of the demand for that particular zone. This can be a good way to tell whether or not your city is ready for a particular density. However, there are several ways to change the default mechanism with hotkeys.
- Shift - Removes any streets that are auto-placed. Zones will still be their computed size.
- Ctrl - Overrides the default zone size and allows you to drag individual cells out to whatever size you want. Be careful with this. If you drop a bunch of 3x3 or 4x4 zones when your city does not have enough demand for the particular zone type, it will not develop! A 2x2 building cannot, for example, develop on a 3x3 zone. That zone has been designated for 3x3 or larger only buildings. However, if you are zoning and lots come out as 1x2 or 2x2, when your city's demand increases and larger buildings become available, larger buildings can build atop the smaller cells, assuming there are adjacent cells that together make up a 3x3, 4x4 or whatever that building calls for.
- Alt - Reverse the orientation of zones as well as the streets placed with zones.
When and Where to Zone?
The RCI indicator is YOUR FRIEND. It is crucial to place zones only when they are demanded by the RCI indicator. Do not place commercial if it is in the negative. When finding the correct place to zone a specific type of building, pay close attention to the desirability and land value maps. You can increase desirability of an area by placing parks, and for residential, placing hospitals and schools as well. With high tech industry zoning it is crucial to ensure that you place only in high desirability areas. If you don't other industry will start to move in, causing the desirability to lower even more. Conversely, placing high tech next to wealthy homes will raise desirability, and the high tech buildings that grow will push the desirability circle out further.
Residential areas hate traffic noise, especially richer citizens. To ensure that your high wealth structures don't dilapidate into ghettos, put effective mass transit in your inner city areas. Suburbs with light residential are easier to manage. Simply starting off with streets and upgrading to roads when congestion hits should be enough to keep the residents happy. In either case, make sure their commute to both commercial and industrial is short, or they will eventually abandon.
It is quite common for someone just starting on SimCity to have trouble properly placing commercial zones in their city so that it doesn't just abandon. The best thing to keep in mind is that commercial likes high traffic areas! If you have a fairly well-established city, look at the traffic volume of your streets on the traffic volume overlay map. Any area in dark blue is a great area to put commercial. Commercial zones also like to be clustered together in their own districts. They can be placed near residential, and high tech industrial (if you must), but don't like being near pollution. Keep in mind that desirability is not the only factor for success on these buildings, but that traffic volume affects them too! Another way to ensure high traffic locations is to place commercial blocks checkered in residential areas. This guarantees that there will be customers, but will make it harder to provide health and educational services for the residential areas (see Providing Services).
Unlike in previous versions of SimCity, it is ok in some instances to place industrial zones next to residential zones. Once you hit the education level required for high tech industry to develop, placing industrial zones meant for high text next to residential will keep the desirability for high tech up in the zones. Also, it helps the residential zone sustain its population as high tech jobs are usually meant for R$$ and R$$$ citizens. High tech industry can also coexist peacefully with manufacturing industry, even though it causes pollution. Residential still wants to be placed away from dirty industry, and high tech industry doesn't particularly like being placed near commercial zones.
Keep in mind that manufacturing and high tech industry will grow not only on high density lots, but medium density as well. Therefore, you can get the same tax benefit from these buildings with much less initial investment cost.
Landfills are tricky. The only thing that will grow next to a landfill is dirty and manufacturing industry, and sometimes R$ and CS$. However, not placing a large enough landfill guarantees that your city will fill up with trash, pulling down property values and preventing high tech industry from developing. I've found that it's best to place this in the corner of a map next to your power plants. If you want, you can use recycling centers to help with the garbage load, but I've found that they are largely ineffective for the price you pay for them. Also, you do not have to keep zoning landfills larger and larger with bigger cities. I've found that 30 squares is about enough for any size city. Just make sure you have enough that it doesn't start climbing out of control. Your advisors will complain that garbage is teetering, but if you look at the garbage location overlay map, you will notice that there is no garbage in your city.