|The 12 Japanese zones|
|Principle of North American zoning: exclusive use per zone|
|Principle of Japanese zoning: zones include all uses up to a maximum "nuisance level"|
|Allowed uses in every Japanese zone|
|Single-family houses and low-rise apartments coexisting in Sendai|
|Same area, as seen from the sky, in green, single-family homes, in red, multifamily apartments|
|Height restrictions in Japanese zoning to avoid eternal shadows|
Note that this guideline also exists in North American cities, but is often bypassed by arbitrary height limits written in every zone..
UPDATE: For an example of the great mix of housing that results from the lack of regulation on housing types, see this article on the housing mix of a small neighborhood in Sendai.