What applies to the operation of vehicles with regard to the height of the vehicle, including the height of the load?

For vehicle operation in Germany, you are responsible for knowing the real overall height of your vehicle at that moment, meaning the vehicle plus anything you’re carrying on top or stacked above it.

Answer 1 is correct because the registration certificate Part I gives you the vehicle’s base height as approved/recorded for that vehicle. That’s a useful starting point, especially for vans, trucks, motorhomes, or vehicles with roof racks.

Answer 2 is correct because as soon as a load sticks up above the roofline (for example on a roof rack or when transporting bulky items), the value in the papers may no longer match reality. You must then determine the actual current height yourself, because you are liable for hitting low bridges, height barriers, or overhead lines even if you “didn’t know” the height.

Answer 3 is not correct because the relevant rule is not “4.5 m maximum.” The key rule of thumb is: you must not exceed the legal maximum height that applies, but the commonly relevant limit for general vehicles is 4.0 m. So you should not rely on 4.5 m; instead, know your real height and make sure it stays within the legal limit and any posted height restrictions.