I've said before in this thread that "you can't regulate taste". I want to clarify that that's not entirely true, it's more a shorthand for "you can't efficiently regulate taste".
In most North American planning systems you have two options for approvals:
- "As-of-right" - i.e. permitted development. You write an explicit set of rules (permitted uses, setbacks, maximum height, landscaping requirements, etc.). The Development Officer's job is to confirm that your proposal meets the requirements and issue you a permit if it does.
- "Discretionary" - e.g. in Nova Scotia this would include development agreements and Site Plan Approval (which used to be used in Downtown Halifax). You establish a set of qualitative criteria, and Council or another body such as a Design Review Committee are responsible for determining if the proposal reasonably meets the qualitative criteria.
It is very hard to fit design regulation into as-of-right permitting. Good design is not just a palate of materials or the presence of certain design features. It is much more about the relationship of various design choices. For every example of bad metal siding, there is a building out there that uses metal siding to great effect. If you prohibit metal siding on the basis that one building with it is ugly, you also prohibit all of the good uses of it.
The best place where as-of-right regulation works really well for design is in heritage contexts. In those situations you have very specific elements that are essential to the narrow character that you're trying to preserve and emulate. For example, you can make a nice metal-clad building, but it will never be appropriate in the context of a Victorian heritage district.
In theory, it's much easier to regulate design through discretionary processes. Now you have a group of people who can look not just at the elements in isolation, but in terms of how they work together and how they fit their surroundings. The problem with this is that it's slow. It takes time to evaluate and it takes time to adjust designs to respond to comments and feedback. Also, there needs to be an appeal process, since we're a society that belives in checks-and-balances on decision makers. The end results is that you're looking at months, if not years, for an approval. That can be reasonable for big, important developments but it's simply untenanble when it comes to small-scale development.
So TL;DR:
- Regulate rigidly through as-of-right. Prevent a lot of good designs along with preventing bad.
- Regulate through a discretionary process, which takes way more time than is reasonable for a small building. Can you imagine the outcry (especially in this housing market) if it took months or years to get a permit for a simple building?
- Don't regulate taste. Yes, you'll get some bad stuff but you'll also get a lot of good.