Understanding NHVR Networks

What Is an NHVR Network?

The National Heavy Vehicle Regulator maintains a digital map of every road in Australia that heavy vehicles can use. This isn't one simple map, it's a set of networks, each defining which roads are approved for a specific vehicle type.

There's a network for B-Doubles. Another for Road Trains. Another for Performance Based Standards (PBS) vehicles. Each network contains thousands of road segments, and each segment has its own access classification.

When Truck Me calculates a route for your vehicle, it queries these networks to ensure every road on your path is approved for your specific truck type.

Networks, Segments, and Access Codes

Networks

A network is the top-level container. It represents a heavy vehicle category, for example, the "B-Double Network" or the "Type 1 Road Train Network". Each network defines which roads across Australia allow that vehicle type.

Segments

Each network is made up of thousands of individual road segments. A segment is a specific stretch of road, it could be a full highway link or a short urban section between two intersections.

Every segment within a network has an access code that tells you whether your vehicle can use it:

• General Access, approved for your vehicle type with no restrictions
• Conditional Access, approved, but with conditions attached
• Restricted, your vehicle type is not permitted on this road

Conditions

When a segment has conditional access, the conditions specify exactly what's required. Common conditions include:

• Weight limits, maximum gross vehicle mass for the segment
• Height clearance, bridge or overhead structure limitations
• Time restrictions, access only during certain hours (e.g., no heavy vehicles between 7–9am in school zones)
• Escort requirements, oversized loads may need pilot vehicles
• Speed restrictions, reduced speed limits for heavy vehicles on certain roads

How Road Access Gets Updated

NHVR network data isn't static. Road managers, typically state transport authorities and local councils, regularly update access classifications. Here's how the process works:

1. Change set created, a road manager drafts a batch of access changes (new segments, modified conditions, or removed access)
2. Segments modified, individual road segments are added, updated, or removed within the change set
3. Review and approval, the changes go through a review process
4. Published to the live network, once approved, the changes go live and map tiles regenerate

This means the road your B-Double used last month might have different conditions today. A new bridge restriction, a changed weight limit, or a reclassified access code can all affect your route.

Why This Matters for Drivers

Most drivers interact with NHVR data through static PDF maps or the NHVR website. The problem is that these resources require manual checking, don't integrate with navigation, and don't alert you to changes.

Truck Me sits on top of the NHVR network data and does three things with it:

1. Colour-Coded Map Overlay

Every road on your map is colour-coded by access status for your selected vehicle type:

• Green, general access, you're good to go
• Amber, conditional access, tap to see the conditions
• Red, restricted, your vehicle type isn't allowed

2. Vehicle-Specific Routing

When you request a route, Truck Me calculates it against your vehicle's network. The route only uses approved roads. If the approved route is significantly longer than the unrestricted route, the app flags which restricted segments are causing the detour, so you can see the trade-off.

3. Change Detection

When you save a route, Truck Me monitors the NHVR network for changes to the segments on that route. If a road's access status changes, a new restriction, a modified condition, a revoked access code, you get a push notification before your next trip.

The Segment Inspector

Tap any road segment on the Truck Me map to see its full details:

• Access code and description
• Active conditions (weight, height, time, escort)
• Road manager contact details
• Active community-reported incidents on that segment

This is the NHVR data made useful, not buried in a PDF or hidden behind a government portal, but available at a glance while you're planning your route.

What Comes Next

NHVR manages 542 API endpoints across 11 services. Truck Me currently uses the Network Service, Routing Service, and Map Service to deliver vehicle-specific routing. As we build out, we'll integrate more of this data, including PBS configurations, notification subscriptions for network changes, and road manager information.

The goal is simple: make NHVR data work for drivers, not the other way around.

Join the waitlist at trucksheet.au to be first in line.