Policy has to land somewhere
A city can adopt goals such as safer streets, more housing, better access for people with disabilities or reduced energy use. Those goals stay abstract until they become something physical: how wide a sidewalk is, where a door faces, how tall a base of a building may be. Urban design is the field that works at that scale, and design standards are one of the main ways public policy reaches the ground.
This article is about that translation. Broader questions about the design of livable places are covered elsewhere on the site; here the focus is on the policy side: how standards are written, who applies them and what can go wrong.
Standards, guidelines and the difference between them
Cities typically use two kinds of design instruments.
Standards are requirements. A building must be set back a certain distance, a ground floor must have a minimum amount of windows, or a street must include a sidewalk of at least a stated width. They are usually specific and measurable, and a project that does not meet them generally cannot be approved without an exception.
Guidelines are softer. They describe preferred outcomes, such as buildings that relate to neighboring heights or entrances that are visible from the street, and leave room for different solutions. Guidelines are usually applied through a review process in which staff or a board judge whether a proposal meets the intent.
Neither is simply better. Standards are predictable but can be rigid. Guidelines are flexible but depend on judgment, which can feel arbitrary to applicants and neighbors alike. Many cities mix them, and tools such as form-based codes and design review boards sit somewhere along that range.
Examples of policy turned into form
The link between goal and design is easiest to see through examples, described here in general terms.
- A policy to support walking might lead to standards on sidewalk width, frequent building entrances, limits on blank walls and requirements that parking sit behind or beneath buildings.
- A policy to reduce traffic injuries might lead to narrower lanes, shorter crossing distances and the sort of measures that fall under traffic calming.
- A goal of access for everyone might appear as requirements for curb ramps and step-free entrances, built on the principles of universal design.
- A climate goal might appear as requirements for tree planting, permeable surfaces or shading along streets.
- A heritage policy might produce guidance on materials, window patterns and the height of new buildings next to historic ones.
In each case the policy itself is a short sentence; the design standard is what determines whether it has any effect.
Where the standards live
Design requirements appear in several places: the zoning ordinance, a separate design manual, street design standards used by the public works department, or district-specific rules such as overlay districts. They may also be attached to public funding or land sales, so that a project receiving public help must meet higher standards than the minimum. Where they sit matters because it determines who enforces them and how easily they can be changed.
Why design standards are contested
Design rules affect cost, speed and who gets to decide. Several tensions come up repeatedly.
Cost. A requirement for particular materials, additional open space or wider sidewalks adds expense, and builders may pass that on in prices or rents or decide not to build. Whether specific standards meaningfully affect housing costs is debated, and the answer varies with local markets.
Subjectivity. Beauty and character are matters of taste. Guidelines that rely on words like “compatible” or “harmonious” can lead to inconsistent decisions, and critics argue that design review can be used to slow or block projects for reasons that have little to do with design.
Uniformity. Detailed rules can produce buildings that look alike, or that mimic a style in a superficial way. Some places try to prevent this by setting out the outcome they want rather than the appearance.
Equity. Design attention is sometimes concentrated in wealthier or more organized areas, while other neighborhoods receive less investment or less scrutiny of new projects. Good policy considers who benefits from a given standard and who bears its cost.
Writing standards that can be applied
Practitioners often point to a few habits that make design policy work better, though none guarantees success.
- Tie each requirement to a stated purpose, so reviewers and applicants know what it is for.
- Prefer clear, measurable language where possible, and reserve judgment for qualities that cannot be measured.
- Use illustrations, since a diagram can often explain a rule more clearly than a paragraph.
- Test standards against real sites before adopting them, to see whether they are buildable.
- Revisit them periodically. Standards written for one era can conflict with later needs, such as accessibility or flood protection.
Design as a check on the whole process
Design review is also a point where the public sees what a project will actually look like. Renderings, models and site plans make a proposal tangible, and early design discussions can surface concerns about shade, noise or access before money is committed. That can help a project, but only if the design standards are clear about what is negotiable.
What design standards cannot do
A design rule cannot create demand for a place, fund the maintenance of a park or ensure that housing stays affordable. It also cannot guarantee that a street will feel safe or lively; those outcomes depend on many factors, including programming, management and who lives nearby. Design is a tool for carrying policy into the built environment, not a substitute for the other parts of policy such as funding, services and community involvement.
Evidence about how much particular design features change behavior or well-being is mixed in many cases, so claims that a single design rule will deliver a given result deserve skepticism. Careful monitoring after a project opens is the most reliable way to learn what a standard actually accomplished.