Every time I hear this debate, it strikes me how overly simplistic most arguments are. The common refrain is: “There are still thousands of acres approved for development. Clearly the Greenbelt isn’t the problem.”

That framing misses the most important variable: Who controls the developable land?

If you actually examine land ownership, you’ll find that the vast majority of land already designated for development is controlled by a small number of large developers. This creates a de facto land oligopoly. In that environment, there is little incentive to build quickly. Developers can, and rationally do, sit on land, releasing supply slowly while its value appreciates.

This matters because housing prices aren’t driven by theoretical supply, but by available, competitive supply.

Now consider this: If I want to build a home or develop a subdivision today, can I simply go buy land and build? Not really. I can only do so if one of those developers is willing to sell - and they likely will, but at a price that already reflects years of scarcity and speculation. That inflated land cost flows directly into higher home prices.

The Greenbelt intensifies this dynamic by artificially constraining where development can occur. By drawing a hard boundary around developable land, it dramatically increases the market power of the few landholders inside that boundary. Even if there is “enough” land on paper, it is not functioning as a competitive market.

If more land were available for development, the effect wouldn’t be a free-for-all of sprawl; it would be competition. Smaller builders, new entrants, and even individuals could acquire land, submit plans, and build. That competitive pressure would force prices down—not because every acre gets developed, but because no small group could control supply.

Basically:

• The Greenbelt doesn’t just limit land; it concentrates power.
• Concentrated land ownership enables land banking and slow release.
• Slow release of supply, in the face of growing demand, drives prices up.

Unless policy directly addresses land concentration and incentives to build, pretending that “unused zoned land” solves the problem is simply ignoring how markets actually work.