Ladders, conduit, pipe and timber don’t fit in a tub, and they’re exactly the loads that cause trouble on the road. Get the rack wrong and you crack a cab roof, bend a rail or lose a ladder on the freeway. Get the load wrong and you’re looking at a fine, or worse.
This guide explains how rack load ratings work, the legal limits for width and overhang, and what to look for when choosing a roof rack or ladder rack. It’s based on the National Transport Commission’s Load Restraint Guide for Light Vehicles, Victoria’s Road Safety (Vehicles) Regulations 2021, and load rating guidance from Rhino-Rack and Yakima, checked in October 2026. Rules outside Victoria may differ, so check with your state road authority. We haven’t tested specific racks.
For storage in the tray or tub, see our ute tool storage comparison.
The three types of rack
| Rack type | Mounts to | Good for | Watch out for |
|---|---|---|---|
| Cab roof rack or roof bars | Roof rails, gutters or fixed points | Light, short loads, a ladder or two | Cab roof load rating, usually the lowest limit |
| Tradesman or ladder rack | Tray, tub rails or a tray frame | Long ladders, pipe, timber, conduit | Weight on the payload, rear overhang |
| Canopy roof bars | The canopy frame | Loads above enclosed storage | Canopy maker’s roof rating |
A ladder rack that runs over the cab and the tray supports a long load at both ends, which is why most trades use one for ladders longer than the tray.
Load ratings: dynamic vs static
There are two kinds of load rating:
- Dynamic load is what the roof or rack can carry while you’re driving. Braking, cornering and bumps multiply the forces, so this is the lower number.
- Static load is what it can hold while parked, and is usually higher. Yakima suggests static capacity is often around three times dynamic as a rule of thumb, but you should check your vehicle’s actual figures.
For ladders and materials, the dynamic rating is the one that applies. Rhino-Rack also publishes a lower off-road rating for unsealed roads, so check that too if you work on rural sites.
Rhino-Rack also notes that ratings can vary between models of the same vehicle, depending on body type, build year and features such as a sunroof. Check your owner’s manual, not a forum post about someone else’s ute.
Working out what you can carry
- Find the dynamic roof load for your vehicle in the owner’s manual or from the manufacturer.
- Find the rack’s dynamic rating from the rack maker, for your vehicle fitting.
- Take the lower of the two.
- Subtract the weight of the rack and accessories, such as ladder rollers and clamps.
- What’s left is your cargo allowance on the roof.
A tradesman rack mounted on the tray doesn’t load the cab roof, but its weight and the load on it come off your payload. Our ute tool storage guide explains how to work out payload from gross vehicle mass.
The legal limits (Victoria and national)
Width. Under Victoria’s Road Safety (Vehicles) Regulations 2021, a load must not project more than 150 mm beyond either side of the vehicle, and the total width must not exceed 2.5 metres.
Front projection. The same regulation limits a load projecting past the front of the vehicle to 1.2 metres.
Rear overhang. The NTC light vehicle guide says rear overhang is limited to 60% of the wheelbase or 3.7 metres, whichever is less, measured from the centre of the rear axle. That applies in all states and territories except Western Australia, which uses 1.2 metres from the end of the vehicle.
Warning flags and lights. If a load projects more than 1.2 metres past the rear, or the end is hard to see from behind, it needs a brightly coloured flag at least 300 mm by 300 mm by day, and a red light visible from 200 metres at night.
Restraint. In Victoria, load restraint must meet the performance standards in the NTC Load Restraint Guide for Light Vehicles 2018. The load must not fall or shift in a way that makes the vehicle unstable.
Restraining ladders and long loads
The NTC guide sets performance standards rather than one approved method, but the principles are straightforward:
- tie long loads at at least two points, and use the rack’s stops or rollers to stop forward movement under braking
- use rated straps or ratchet tie-downs, not ocky straps for anything heavy
- check straps after the first few kilometres, because loads settle
- bundle pipe and conduit so single lengths can’t slide out
- keep heavy items low and close to the centre of the vehicle
Straps, flags and locks on Amazon Australia
Affiliate links (paid links). Open Amazon in a new tab. Check strap ratings, and that a flag is at least 300 mm by 300 mm.
Choosing a rack
- Fitment. Buy a rack made for your exact vehicle and body type. The fitting kit is part of the rating.
- Ratings in writing. Look for a published dynamic rating for your vehicle fitting.
- Material. Aluminium is lighter, so you get more cargo allowance. Steel is heavier but tough.
- Ladder features. Rollers, side loaders and lockable ladder clamps make one person loading safer and help against theft.
- Noise and fuel. Roof racks add wind noise and drag. Wind deflectors and removing bars when not needed help.
- Installation. Follow the maker’s torque settings, and re-check bolts after the first drive and regularly after that.
Security
Ladders and copper pipe on an open rack are common theft targets. Lockable ladder clamps, a cable lock through the rungs and parking in a locked garage overnight all help. Check your tools insurance, because some policies have conditions for items left on or in vehicles overnight.
Common mistakes
- Ignoring the rack’s own weight. A steel tradesman rack and ladder clamps can use up a big part of your roof or payload allowance before you load anything.
- Using the static rating. The higher figure on a box or forum is often the parked rating. It doesn’t apply on the road.
- One strap on a long load. A single strap lets ladders pivot and slide. Use at least two tie points and a forward stop.
- Forgetting the flag. A long ladder that sticks out the back needs a flag, and a light at night.
- Loose bolts. Fittings can loosen with vibration. Check them regularly.
- Wrong fitting kit. A rack made for a different body type may not be rated for your vehicle.
Interstate trips
The national rear overhang rule applies in every state and territory except Western Australia. Other details can differ, so check the rules with the road authority in each state you’ll drive through, especially for oversized loads.
Quick checks before every trip
- Is the load within the lowest roof or rack rating?
- Is it within 150 mm on each side and 2.5 metres total width?
- Does anything project more than 1.2 metres past the rear? Flag it.
- Is the rear overhang within the lesser of 60% of wheelbase or 3.7 metres?
- Are straps tight, and is the load stopped from sliding forward?
Common questions
What's the difference between dynamic and static roof load?
Dynamic load is the weight a roof or rack can carry while the vehicle is moving. Static load is the weight it can hold while parked, such as a rooftop tent with people in it, and is usually higher. For ladders, pipe and timber, use the dynamic rating, and remember it includes the weight of the rack itself.
How far can a ladder stick out the back of my ute?
Under the national light vehicle guide, rear overhang is limited to 60% of the wheelbase or 3.7 metres, whichever is less, measured from the rear axle, in all states and territories except Western Australia. Projections more than 1.2 metres past the rear, or that are hard to see, need a brightly coloured flag at least 300 mm by 300 mm by day and a red light at night.
Can a load stick out the side of my ute?
Only a little. In Victoria, the Road Safety (Vehicles) Regulations limit side projection to 150 mm on each side, and the total width of the vehicle and load must not exceed 2.5 metres.
Do I need a tradesman rack or a roof rack?
A tradesman or ladder rack mounts over the tray or tub and usually carries longer loads with better support at both ends. A cab roof rack is lighter and lower but is limited by the cab roof rating. Many tradies use both, or a canopy with roof bars.
