by Barry Watkins from the B.A. Watkins blog 9/16/11
Mixed Use and the Walkable Neighborhood
In this article I refer to the SmartCode. If you’re not familiar with it you may jump over to the SmartCode Central site for more information and for free downloads.
When planning places for walkability there are several things we really need to “get right” in order to really achieve our goals. One of those things we need to get right is planning the optimal mix of uses within our planning area. The SmartCode, the New Urbanist model land development code, gives us a good pattern to follow and using it is a great way of making sure we get the right balance. Each neighborhood, for walkability, should be composed of several habitats varying the environment experienced within the neighborhood from edge to center. The SmartCode accomplishes this through the use of the Transect Zone. Transect Zones T1 through T6 describe a range of habitats from rural to urban, T1 being the most rural of the zones, T6 being the most urban. When using the SmartCode, neighborhood centers are zoned more urban and the neighborhood edges are zoned less urban. This provides focus for growth and activity within the neighborhood. Higher urbanization being near the geographic center of the neighborhood acts like a magnet for creating higher pedestrian activity where it’s most desired.
In the SmartCode every zone in the walkable neighborhood is mixed-use. The higher zones get a higher mix of commercial than the lower zones. This is one of the elements that produces varied character within different parts of the neighborhood. For example, the Traditional Neighborhood, one of the community types within the SmartCode, is composed of Transect Zones T5 (Urban Center), T4 (General Urban), and T3 (Sub-Urban). Each of these zones gets a different mix of residential and commercial. We can describe the mix in terms of mixed-use units, 1 mixed-use unit = 1 residential unit or 1,000 sf of commercial floor area. The T5 Urban Center zone will be located near the geographic center of the neighborhood and gets a mix of 30-50% commercial units, 50-70% residential. The T4 General Urban zone is to be 20-30% commercial, 70-80% residential. And the T3 Sub-Urban zone will be assigned 10-20% commercial units, 80-90% residential.