Driving with a mattress on the top of your roof is safe if it is done properly.
How to drive with roof bag safe.
A 2012 study conducted by the government accountability office found 51 000 crashes occur each year from cars that were struck by improperly secured objects flying off moving cars or that hit highway debris resulting in 10 000 injuries and 440 deaths.
Your car will have a maximum permitted roof load.
If you don t know what it is then look in your vehicle handbook.
Then weigh luggage items before you load them into the roof box.
You need to be aware that your car will handle differently when you have a roof box attached.
Find out the weight of your roof bars and roof box.
Since suvs are already higher off the ground adding a roof carrier can mean more wind resistance added potential for swaying and lower gas mileage.
Always use the recommend fixtures and accessories.
Prevent items from moving during a sudden stop by strapping down bags or boxes with cargo anchors.
Make sure you have the proper tools and help when securing the mattress to the top of your roof.
Furthermore stay off busy roads and highways.
The owner s manual for your car will have a section on the maximum weight that can be carried on the roof.
Oh and don t forget to add the weight of the roof rack to your calculations too.
We often find the car will have a lower weight limit than the roof bars so it s important to check and never exceed whichever is the lower of the two.
Add all these weights together to make sure you haven t exceeded the roof load capacity.
It can be dangerous to drive with objects strapped to the roof of your car especially for the vehicle behind you.
Don t load your roof with lots of heavy items anything heavy is better stored in your boot.