The problem with this sort of balancing act is that most zoning isn't centrally planned enough that you can actually balance this. Most of the time you are planning one small section of a larger urban/suburban complex, not the entire country. So you have to consider inflows and outflows of both commercial and residential demand.
If more people want to live in your city than you currently have housing for, then it's not simply a matter of "balancing zones" anymore. Your plans no longer match reality, and one of four things can happen:
- Your zoning remains static and housing prices rise according to demand, pricing people out of the market
- You hope businesses leave so that you can convert some of the commercial space to residential
- You decide to allocate existing zones on some criteria other than willing price paid
- You zone for higher density and allow existing homeowners to make money by making room
The first option is gentrification. The do-nothing option. The one that we're trying to avoid because we find it distasteful. If we don't fit more people in the city then it becomes a playground for bored rich people as the market will kick everyone else out.
The second option usually doesn't happen - residential demand drives commercial demand because most businesses want to be close to people. If businesses are leaving, that usually means that people are leaving, too. This also means that balancing zones isn't really a thing you need to actually do. The problem isn't that the space is being used inefficiently; the problem is that there isn't enough space to go around.
The third option is rationing. This takes many forms, and is politically popular with basically everyone. But it doesn't actually solve the problem: there are still more people who want to live in your city than houses to put them in. You're just choosing a different way to allocate those houses, and invariably it tends to be a metric that's easier to corrupt, because suppliers now have an incentive to charge rich people more to bypass the system.
The fourth option will actually fix the problem; and in fact is the only way to fix the problem. But it's also the easiest to politically oppose, because we've set the standard here in America that land is supposed to be divided entirely between large shopping centers and low-density suburbs; and that living in anything else is a symbol of urban poverty. This actually isn't true anymore - the areas worst hit by gentrification are also the ones zoned for high density or mixed use, and this is precisely because of people making it difficult to upzone property.
If we didn't have zoning, or at least had less of it[0], then the market could actually work to incentivize resupply rather than just redevelopment. Then we could talk about social housing or housing subsidies on the demand end, knowing that we have a market that actually responds to supply rather than just pocketing the wealth.
[0] e.g. Tie the planners' hands a bit and just have mixed commercial/residential zones of varying densities, with industrial land use separated out for safety/noise reasons. Japan does this.
If more people want to live in your city than you currently have housing for, then it's not simply a matter of "balancing zones" anymore. Your plans no longer match reality, and one of four things can happen:
- Your zoning remains static and housing prices rise according to demand, pricing people out of the market
- You hope businesses leave so that you can convert some of the commercial space to residential
- You decide to allocate existing zones on some criteria other than willing price paid
- You zone for higher density and allow existing homeowners to make money by making room
The first option is gentrification. The do-nothing option. The one that we're trying to avoid because we find it distasteful. If we don't fit more people in the city then it becomes a playground for bored rich people as the market will kick everyone else out.
The second option usually doesn't happen - residential demand drives commercial demand because most businesses want to be close to people. If businesses are leaving, that usually means that people are leaving, too. This also means that balancing zones isn't really a thing you need to actually do. The problem isn't that the space is being used inefficiently; the problem is that there isn't enough space to go around.
The third option is rationing. This takes many forms, and is politically popular with basically everyone. But it doesn't actually solve the problem: there are still more people who want to live in your city than houses to put them in. You're just choosing a different way to allocate those houses, and invariably it tends to be a metric that's easier to corrupt, because suppliers now have an incentive to charge rich people more to bypass the system.
The fourth option will actually fix the problem; and in fact is the only way to fix the problem. But it's also the easiest to politically oppose, because we've set the standard here in America that land is supposed to be divided entirely between large shopping centers and low-density suburbs; and that living in anything else is a symbol of urban poverty. This actually isn't true anymore - the areas worst hit by gentrification are also the ones zoned for high density or mixed use, and this is precisely because of people making it difficult to upzone property.
If we didn't have zoning, or at least had less of it[0], then the market could actually work to incentivize resupply rather than just redevelopment. Then we could talk about social housing or housing subsidies on the demand end, knowing that we have a market that actually responds to supply rather than just pocketing the wealth.
[0] e.g. Tie the planners' hands a bit and just have mixed commercial/residential zones of varying densities, with industrial land use separated out for safety/noise reasons. Japan does this.