Fund deed restrictions to limit house sizes.
As Boulder struggles to finance and build affordable housing, smaller houses all over town are being razed and replaced by expensive larger homes. We can maintain economic diversity in the city if we can find ways to preserve the small and midsize housing stock that already exists.
Many efforts to control housing affordability negatively impact owners of affected properties. New rules limiting what can be built may reduce the the value or appreciation potential of a current owner's property. Designating housing as permanently affordable has the same effect.
One way to limit the gradual increase in house sizes without these impacts would be to pay owners of smaller homes to add a deed restriction, similar to a conservation easement, that prevents a larger home from ever being built on their lot. The restriction wouldn't prevent modernizing or improving the property, but it couldn't be expanded or replaced with a larger structure. Although this restriction would have the (intended) effect of limiting appreciation, the owner would be compensated. Many homeowners would like the opportunity to get an immediate financial benefit rather than waiting until they sell. Unlike permanently affordable housing, deed-restricted homes would still appreciate at market rates, but the restriction would limit upward pressure by reducing their appeal to developers and to high-income buyers who want a large house.
Buying deed restrictions could be cheaper for the city than building new housing. A formula based on the difference between the square footage of the current home and the largest house that could legally be built on the lot could be used to determine the value of the restriction. Fees on new development can fund this.
Boulder's location and natural beauty will always force prices higher. Given a fixed supply of land, the only way to counter the force of increased demand is to somehow make the town less desirable. We seem to be caught between a choice of making the city less desirable by increasing either density or economic exclusivity. An effort to preserve smaller housing provides a middle ground by keeping density constant while reducing desirability in a way that is fair, preserves the character of the town, and helps maintain economic diversity.