Functional Class
You will hear the phrase Functional Class or FC a lot when it comes to the standard for road types. According to the US Federal Highway Administration, The concept of functional classification defines the role that a particular roadway segment plays in serving the flow of traffic through the network. Waze has its own interpretation of this system, but it utilizes the state's functional class map to help determine the road type to use.
Check out our Mapping Resources for knowledge on how to use the state's map system to find Functional Classifications Standards in Iowa. From that knowledge, use this chart to determine how the road should be classified using the Waze Standard. Iowa follows this chart completely aside from dirt or gravel roads in rural areas. This exception will be changed as soon as an unpaved road option exists in Waze.
If you have any questions about Functional Class, please use our Community Resources to reach out to gain further information.
Below is a list of the six major road types. If you click on the button of the road type, for instance Freeway , you will be directed to a Wiki section that discusses the road type further.
Freeway
A Freeway is the highest functional class of road. It is designed for higher speeds and limited to entrance and exits ramps being the only way to enter or exit this type of road.
Any road with the Functional Class (FC) as Principal Arterial Interstate, colored blue on the FC map, will be considered a Freeway. All Interstate Roads Will be freeways aside from Business Loops and Spurs (Which instead will be a Major Highway). Also, watch for some roads that are Principal Arterial - Other or Other Freeways (colored red or orange) as they could fit the profile of a Freeway. All roads that have to be entered or exited using a ramp, where 3 or more consecutive exits occur, needs to be set as a freeway. A Freeway will end at first direct connection of a road to the highway.
Naming
- Freeways will usually only be named the Highway number of the most prominent highway of the section. For instance, If a highway is a State Highway connected with a US highway, then it will be named the US highway.
- If two of the same type connect such as a US highway and another US highway, then the road that stayed on course will be the named highway.
- All highway numbering will be as follows: Interstate: I-XXX, US Highway: US-XXX, Iowa State Highway: IA-XXX, County Highway: CR-XXX. Notice that there are no spaces between the dashes. The only exception to using the Highway Number would be if there is clear signage that the freeway is known by another name.
Ramps
A Ramp will connect two roads together; however, it will not be used for a simple At-grade connector or in other words a road that doesn't have a different elevation level. There are some exceptions to this rule to understand.
Naming
Even veteran editors need to pay attention here! Naming of an entrance and exit ramp correctly is crucial to the users of this app when being navigated around. If the name of the entrance ramp is incorrect it will confuse the experience and may confuse the driver to take the exit absurdly or miss it all together. Please follow these rules:
- Only time to ever type in the word "Exit" in the ramp is when the exit is a numbered exit. The only roads that have numbered exits are exits off an Interstate with the exception of US-52.
- For all Numbered exits, it will start with "Exit XX:" For example, if the Exit is number 114A then you will start the exit name as "Exit 114A:" and there will always be a colon after the exit number
- For non-numbered exits, just start the exit as such, "to" For example, if the exit was to US Highway 169 Northbound, then the exit would be "to US-169 N"
- All numbered highways need to be typed as such: Interstate: I-XXX, US Highway: US-XXX, Iowa State Highway: IA-XXX, County Road: CR-XXX all with no spaces between the Highway type and the number.
- Include as much information in the sign as possible. For example, If the actual sign shows it will take you to County Highway 1 Eastbound and it also takes you to Riverview Rd and Old Shakopee Rd, then the ramp needs to be labeled: "to CH-1 E / Riverview Rd / Old Shakopee Rd" using the slash "/" to separate the different roads to take. Try to match the sign as close as possible.
- If a road splits showing arrow marking under lanes to of which to stay on to continue your course, use ramps for each side. For example: in Burnsville, a person taking I-35 N will have the decision to take I-35W N or I-35E N. The I-35W side is a numbered exit, the other side is just a guided direction to head towards I-35E N. The one side is labeled: "Exit 88A: I-35W / Minneapolis" and the other side is just labeled: "to I-35E / St. Paul". Using ramps here will guide the driver to the right side of the highway.
- For road splits that have 3 or more splits, usually paying attention to the one that splits first will guide you to how to set it up correctly, but it is often best to reach out for support to find the best solution based on the more complexity of an issue.
Major Highway
A Major Highway is a primary route for traveling throughout the country, from one city to another, over long distances.
Any road with the Functional Class (FC) as Principal Arterial - Other (Freeways), colored red or orange on the FC map, will be a Major Highway (MH) if these roads do not fit the standard definition of a Freeway. All US Highways (Such as US-169) will be labeled as a Major Highway regardless of what the FC map shows unless it can be labeled as a freeway.
Naming
- Naming of a major highway typically will be in the road number standard: US Highway: US-XXX, Iowa State Highway: IA-XXX, County Road: CR-XXX; however, pay close attention to the way the signage really is in these areas.
- In town, these highways need to be named as the street names used for house numbering.
- Out of town, should be labeled the same as the street name for house numbering if looking at a 2 lane highway
- and the Highway number for split direction Major highways unless signage clearly indicates it is known by another name
Minor Highway
A Minor Highway is a secondary route for traveling between cities over moderately long distances.
Any road with the Functional Class (FC) as Minor Arterial, colored as green on the FC map. will be a Minor Highway (mH). Also, all State Highways (such as MN-13) will be set at a minimum of a minor highway regardless of the current FC classification from the State of Iowa unless it is a higher classification or could be considered a freeway.
Naming
- Naming of a minor highway typically will be in the road number standard: Iowa State Highway: IA-XXX, County Road: CR-XXX; however, pay close attention to the way the signage really is in these areas.
- In a town or city, the naming will typically be the street name unless the name of the street is Co Rd XXX where we would change it to CR-XXX
- Pay close attention to the name assigned for house numbering. If house numbering suggests using the wording, "State Highway XXX", we need to set the name of the road as such.
Primary Street
A Primary Street is a road used with medium-low traffic densities which are used to bring traffic from local streets to arterials and vice versa
Any road with the Functional Class (FC) a Major or Minor Collector, colored as purple or yellow on FC map, will be a Primary Street (PS). Also, pay attention to any paved county road as these will have a minimum of a Primary Street. Most frontage roads will have this category as well even if the FC map shows a lower level (but reach out for clarification for the ones that are not a county road). If you see any of these roads set as a service road, please correct this to a standard type road as Service Roads are phased out.
Naming
Primary streets should only be named the actual name of the street (same name as house numbering indicates). The only exceptions to this rule would be County Roads in rural areas.
County Roads In Iowa
Iowa adopted its present county road numbering system in the late 1960's, featuring alphanumeric route numbers on the blue pentagon signs that are also used in many other states. Before that, county roads were given single-letter or double-letter designations, much like Wisconsin's county trunk roads and Missouri's state supplementary roads.
- East-west county roads start with "A" in the northern part of the state and ascend alphabetically until reaching "J" in the south. Example: Johnson County Road F46.
- North-south county roads start with "K" in the western part of the state and run all the way through "Z" in the east. Example: Scott County Road Y40.
- Diagonal county roads use letter-number-letter route designations instead of the usual letter-and-two number route; the letters used correspond to the letters of other county roads in that area. Examples: Linn County Road W6E, Clayton County Road C9Y. A few four digit county roads exist, though, including Lyon/Sioux County Road A54B, Delaware County Road C60X, Jackson County Road E23Y, and Louisa County Road G44X.
- Four letters — I, O, Q, and U — are not used in route numbering. ("I" may be too similar to the number "1," plus Interstate highways are also referred to as "I-xx" routes. "O" and "Q" are too similar to "0" (zero), and "U" is too close to "V.")
- Letters tend to change about every 20 to 25 linear miles; they usually do not change with county lines (except for the horizontal roads in western Iowa).
- Numbers generally run from 10 through 80, ascending from west to east and north to south.
- Numbers can be duplicated in multiple counties on multiple discontinuous routes.
- Cardinal direction markers are seldom used, since the first letter should tell you whether it is an east-west or north-south route.
- County roads are usually not signed in the city limits of larger cities, as the city usually takes over jurisdiction of the road at that point. Example: County Road W66 runs along Dubuque Street north of Iowa City and Gilbert Street south of there, but it is not signed in the city limits.
Street
A Street will be for any road in a town or city that doesn't fit in the categories above. In rural areas, this will be lightly used for paved roads that cannot be considered a County Road (a rarity in the rural areas). This will be named the same name used for house numbering.
Quick reference chart
Refer to this chart to determine the road type of a given paved public road based on the functional class.
To use this chart, first determine the functional class of a road, and whether it is a signed, numbered highway in a particular highway system.
Where the column for the road's highway system and the row for the road's functional class meet, you will find the proper road type for that particular road.
A number of examples are given below the chart.
Always consult an Area or State Manager if you are unsure of what class to give a road.
Highway Systems | |||||||||
---|---|---|---|---|---|---|---|---|---|
Interstate | Interstate Business Loop/Spur | US Hwy (incl. some special routes) | US Hwy BUS, SPUR, LOOP | State Hwy (incl. some special routes) | State Hwy BUS, SPUR[a], LOOP | County Routes | Locally-maintained | ||
example | I-80 E | I-35 Business | US-20 | US-30 Business | IA-1 | IA-60 Business | CR-M15 | Robertson St | |
F u n c t i o n a l C l a s s |
Interstate[b] | Fw | n/a | n/a | n/a | n/a | n/a | n/a | n/a |
Other Freeways & Expressways[c] | n/a | Fw [g] | Fw [g] | Fw [g] | Fw [g] | Fw [g] | Major | n/a | |
Other Principal Arterial[e] | n/a | Major | Major | Major | Major | Major | Major | Major | |
Minor Arterial[f] | n/a | Major | Major | Minor | Minor | Minor | Minor | Minor | |
Major Collector | n/a | Major | Major | Minor | Minor | PS | PS | PS | |
Minor Collector | n/a | Major | Major | Minor | Minor | PS | PS | PS | |
Local/not mapped | n/a | Major | Major | Minor | Minor | PS | PS | Street |
^a When a state highway "SPUR" route is used to connect a state highway with another state highway, a US highway, or an Interstate (i.e., when it is used as a connector/CONN route), use the first state highway column.
^b Also known as Principal Arterial - Interstate.
^c Also known as Principal Arterial - Freeway.
^d Also known as Principal Arterial - Expressway.
^e Also known as Principal Arterial.
^f Also known as Other Arterial.
^g Could also be Major Highway
For example,
- An Interstate Business Loop classified as a Minor Arterial is a Major Highway .
- A US Highway classified as a Minor Arterial is a Major Highway .
- A US Highway Spur route classified as a Minor Arterial is a Minor Highway .
- A State Highway classified as an Other Freeway is a Freeway .
- A State Highway classified as a Collector is a Minor Highway .
- A County Route classified as a Minor Arterial is a Minor Highway .
- A County Route classified as a Collector is a Primary Street
- A locally-maintained road classified as an Other Principal Arterial is a Major Highway .
- A locally-maintained road classified as a Collector is a Primary Street .
Fw | Freeway |
Major | Major Highway |
Minor | Minor Highway |
PS | Primary Street |
Street | Street |
Locking standard
In Iowa we have a set minimum standard for locking roads based on segment type. Any road of a certain segment type must be locked at least to the rank (level) in the chart below. Roads may be locked higher for protection and special situations (areas with construction, tricky design, frequent mistakes, imaging inaccuracies, and the like), but should not be locked lower.
A great time to implement these locks is while bringing the road types of an area into compliance with the current US road type standards (FC and highway systems). Lock the roads based on type after they've been set to current US road type standards.
Segment Type | Statewide |
---|---|
Freeway | 4 |
Ramp | Highest rank of connected segments |
Major Highway | 3 |
Minor Highway | 3 |
Primary Street | 2 |
Street | 1 |
• • • • Ferry • • • • | 5 |
|-|-|-|-|-|-|-|-|-| Railroad |-|-|-|-|-|-|-|-|-| | 2 |