Street Types & Classifications
Every pattern page in this guide is sorted two ways: by its Functional Classification and by its Street Typology. Those aren't everyday words, so this page explains what they mean, in plain language, before you run into them everywhere else in the guide.
#The question every street has to answer
Every street is pulled between two competing jobs: helping people move through quickly, and helping people access the homes and businesses along it. A street can't fully do both at once. A road built for fast through-traffic works badly as a place with driveways and parked cars every few feet; a residential street built for slow, safe access to houses works badly as a high-speed route across town.
Functional Classification is just naming where a street sits on that trade-off. Commonway System uses four:
| Classification | Job it's built to do |
|---|---|
| Local | All access, no through-traffic. Getting to your house or a nearby business is the entire point. |
| Collector | A middle step. Gathers traffic from Local streets and feeds it onto bigger roads. Some access, some movement. |
| Arterial | Mostly movement. Built to carry traffic efficiently across a larger area, not to serve driveways directly. |
| Freeway | Pure movement. High speed, no direct access to anything at all, not even a single driveway. |
There's a real-world example of what goes wrong when a street tries to do both jobs badly at once: it's called a Stroad, a road that tries to move fast traffic and serve strip-mall driveways and parking lots at the same time. It ends up dangerous for the same reason a car can't be a good boat: trying to do two very different jobs at once usually means doing neither one well. Commonway System flags Stroad as a pattern to avoid, and most of what a Collector or Arterial page in this guide recommends is really just a way of keeping those two jobs from colliding.
#Why a bike path or a bus route gets a car-sounding label
You'll run into pattern names like "Collector" attached to a bike path, or "Local" attached to a bus route, and that can look like a mistake at first. It isn't. Functional Classification isn't really about cars, it's about the job being done, and any mode of travel can do any of these jobs.
A dedicated bike path connecting one neighborhood to another is doing exactly the job a car Collector does, just for bikes instead of cars, so it's classified as a Collector. A car-free plaza that exists purely so people can walk to shops and linger is doing the same job a residential street does, just without cars, so it's classified as Local. The same logic sorts transit: a neighborhood bus loop plays a Local role, a bus route feeding a larger transit line plays a Collector role, a light-rail spine crossing a whole city plays an Arterial role, and commuter or heavy rail plays a Freeway-scale role. Once you're thinking in terms of the job rather than the vehicle, the classification makes sense for any mode.
#From classification to a specific street
Knowing a street's Functional Classification tells you its general job. It doesn't tell you the specific situation it's handling. That's what a Street Typology is: a named, specific pattern within a classification, built for one clear purpose.
Think of it like this: Functional Classification answers "what job is this street doing?" Street Typology answers "what particular kind of street is doing that job?" An Alley and a Main Street are both Local, both are pure access with no through-traffic, but they're built for completely different situations: one is a service lane behind buildings, the other is a shopping street meant for browsing on foot. Same classification, very different street.
Every classification has a Default Typology: the standard, ordinary version of that classification, with no special situation attached. A pattern only gets its own named Typology when it's built around something specific enough to deserve a name of its own, a particular access pattern, a particular land use, or a single mode getting full priority.
#Every Street Typology in the guide
#Local
| Typology | What it is |
|---|---|
| Default | The standard neighborhood street. No special job beyond getting people to and from home. |
| Alley | A narrow service lane behind buildings, mainly for deliveries, trash pickup, and driveway access. |
| Cul-de-sac | A dead-end residential street that loops back on itself. |
| Frontage/Service Road | A quiet local street running alongside a busier road, keeping people out of fast through-traffic. |
| Main Street | A local street lined with shops and restaurants, built for browsing on foot as much as driving. |
| Living Street/Woonerf | A street where people walking and biking always have the right of way, and cars are guests, not the priority. |
| Yield Street | A low-traffic street with no dedicated travel lanes; whoever's already there has the right of way. |
| Festival Street | A street that closes to cars for markets or events, and behaves like a normal local street the rest of the time. |
| Pedestrian-only Street/Plaza | Closed to vehicles entirely, built just for walking and sometimes biking. |
| Local Transit | A street built around a neighborhood bus or streetcar route. |
| Bicycle Boulevard/Neighborhood Greenway | A quiet residential street specifically designed to prioritize bikes over car traffic. |
| School Street | A street that closes to car traffic during drop-off and pickup to keep kids safe. |
#Collector
| Typology | What it is |
|---|---|
| Default | A standard street that gathers traffic from Local streets and feeds it onto bigger roads. |
| Rural Collector/Farm-to-Market Road | A collector serving farms and rural areas, carrying both people and agricultural traffic. |
| Industrial Collector | A collector built to handle truck traffic serving warehouses and industrial sites. |
| Bike Highway/Greenway | A dedicated, physically separated path built specifically for bikes over real distance. |
| Collector Transit | A collector street built around a dedicated bus route. |
#Arterial
| Typology | What it is |
|---|---|
| Default | A major road built to move traffic efficiently across a larger area, without driveways or on-street parking interrupting the flow. |
| Boulevard | A grand arterial, often with a landscaped median and sometimes separate slower side lanes for local access. |
| Scenic Highway/Byway | An arterial through a scenic or rural landscape, where the drive itself matters as much as the destination. |
| Arterial Transit | A major road built around dedicated bus rapid transit or light rail. |
| Stroad | A hybrid that tries to be both a fast through-road and a shopping strip at once, and does neither safely. This is the pattern Commonway System is built to help communities move away from. |
| One-Way Street | Traffic moves in one direction only. Tends to encourage speeding, so it's discouraged except in specific situations. |
#Freeway
| Typology | What it is |
|---|---|
| Default | A limited-access, high-speed road with no traffic lights or driveways, built purely to move large volumes of vehicles. |
| Expressway | A slightly less restricted freeway variant, still built purely for movement. |
| Beltway/Ring Road | A freeway that loops around a city rather than cutting through its center. |
| Freeway-scale Transit | Heavy or commuter rail running at the same scale as a freeway corridor. |
#Intersections & Crossings
Every classification above describes a stretch of street. Intersections & Crossings is different: it describes how two streets meet, and it applies across all four classifications rather than belonging to just one.
| Typology | What it is |
|---|---|
| Roundabout | A circular intersection that keeps traffic moving continuously instead of stopping. Commonway System's default choice for busier intersections. |
| Turbo-Roundabout | A larger, multi-lane roundabout for high-volume intersections between two major roads. |
| Signal | A traditional traffic light, used only when a roundabout genuinely isn't practical. |
| All-Way Stop | A four-way stop. |
| Stop/Yield | A basic two-way stop or yield-controlled intersection. |
| Continuous Sidewalk/Raised Junction | A crossing where the sidewalk stays level and uninterrupted, and cars ramp up over it, rather than the sidewalk dipping down for cars. |
| Uncontrolled | An intersection with no signs or signals at all, appropriate only where traffic is very light. |
| Midblock Pedestrian Crossing | A marked crossing placed in the middle of a block rather than at an intersection. |
| Driveway/Curb Cut | Where a driveway meets the street. |
| Grade-Separated Interchange | A freeway-scale interchange where roads cross at different heights entirely, like an overpass. |
#Why this matters once you're reading a pattern page
Every pattern's ID starts with its Functional Classification, follows with a code for its specific Typology, and ends with a number, for example LOC-DEF-01 for the standard Local street. Once you know what those two words mean, that ID stops being a string of letters and starts telling you something: which of the four jobs this street is doing, and which specific version of that job it is. See How to Read a Pattern for the rest of what a pattern page's ID card tells you, and Density Tiers for the other axis every pattern page is sorted by, alongside classification and typology.