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If you look into the roof of your SUV, you may have noticed that there are ridges on both sides. With that said, have you ever wondered why vehicles like vans, trucks, and SUVs have ridges on the roof?
Vehicles with large roof areas usually have ridges to maintain its strength and structural integrity. This design keeps the large metal sheet on the roof from resonating and fluttering when the car is moving on highway speeds. Moreover, it also adds to the aerodynamics of the vehicle.
To make the roof more structurally sound, try putting a piece of paper horizontally in front of an electric fan. When it’s flat, it offers little to no resistance to the wind. Now try, folding it a few times until it has several creases—and you can easily observe it doesn’t flutter as much.
Stamping the ridges makes the roof more stable and rigid. This way, you can make the metal sheet on the roof stronger without having to make it thicker. Thus, ridges also save you a bit of headspace.
Now, imagine if automakers didn’t know this manufacturing technique. Instead of ridges, they might have added additional braces to the body panel to ensure that the roof is secured and won’t easily come off.
What Are Roof Ridges Exactly?
Most large vehicles such as pickup trucks, SUVs, and vans have ridges or small channels on their roofs. They can range anywhere between two to 12 indentions, depending on the design of the vehicle.
Car manufacturers use a technique called pressing or stamping to create these small channels. By bending the metal sheet, it increases the overall resistance of the roof.
Whenever an external force is applied to the slightly bent metal sheet, its shape redirects the energy to multiple directions. Much of the force is reduced as it travels away from the part it came in contact with first.
Consequently, these ridges also allow the roof to withstand more weight that you put on top of it. As such, it also helps in ensuring that the whole roof and the body of the car can carry the load you put on the roof rack.
Depending on who you ask, roof ridges somewhat make the vehicle look sportier. Most SUVs, for example, use contours and indentations to look more chiseled. However, you can only appreciate this design if you are looking at the vehicle from a higher vantage point.
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Some Car Owners Don’t Like Roof Ridges. Why?
It’s quite rare to find roof ridges on smaller cars like sedans, hatchbacks, and convertibles.
However, not everyone is happy with their car’s roof ridges. While it’s quite understandable that they fulfill an important function, these channels also bring some problems.
Below are some of the disadvantages of having roof ridges in your vehicle:
1. They Collect Water and Sometimes Snow
Roof ridges often gather water fast, especially when the vehicle is left alone in the rain. The water can then pour on your front window and even drip around the doors.
Don’t let that happen to you. Get an SUV cover that protects your prized vehicle not just from snow, but also from rain, dust, and excessive sunlight.
2. They Are Hard to Clean
Another issue that some people have with roof ridges is they easily catch dirt. Because they are on an elevated part of the vehicle, you need to use ladders or a tall chair to reach them.
Make it easier for yourself. Clean your car with this cleaning kit.
3. It Makes Polishing the Roof a Bit Complicated
If you previously owned a small car, like a sedan, then you might not be as familiar with cleaning the roof of larger vehicles. Parallel roof ridges also make the work a bit harder because you need the right size of the polisher to get through those hard-to-reach places.
4. It Takes Away Some of the Aesthetics
While this is a bit subjective, some people don’t like roof ridges because it takes away some aesthetic value. For example, roofs of smaller cars have a very smooth surface without these small channels.
You have an option to add a roof rack though. This effectively camouflages the ridges on your roof line and add another level of usable space on your SUV. Get the MAXXHAUL Steel Roof Rack for that.
For a more minimalist approach, you could also get the SANHIMA Universal Roof Rack Crossbars. It functions basically in the same manner without being too overtly exposed. Just make sure you secure your cargo further with the EZYKOO Cargo Net.
You can also add another level of protection to your cargo by using a Car Top Carrier Roof Bag.
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Can I Remove These Ridges?
Some car owners have an evident distaste for roof ridges that they want it removed or leveled. Unfortunately, you can’t just cut it away and sand it after because it will damage the overall structure of your roof.
Removing the ridges can also affect the driving performance of the car, especially when you are going at high speed. The last thing you would want is your car’s roof blowing off because it can’t withstand the drag force.
Furthermore, without these ridges, the roof might easily be damaged whenever a hard object hits it. For example, if you are loading cargo into your roof rack and your bowling ball fell on the roof, it may easily bend, given its less structurally stable.
Altering your roof ridges might also be a disadvantage if ever you decided to sell your car. The buyer might be a bit concerned about the removed roof ridges and how it may have lost its rigidity.
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Why Don’t Sedans and Smaller Cars Have Roof Ridges?
There are only a handful of small cars that have ridges on the roof. Often, these are the boxier hatches, which are bordering the size of compact crossover SUVs. And there are quite a few reasons for doing so.
Furthermore, whenever these smaller cars have parallel roof ridges, they are just quite a few. You often will see two or more short ridges to reinforce the roof’s rigidity. The small channels also improve the car’s aerodynamics by a bit.
But, why is it that that roof ridges are more commonly found on larger vehicles?
If you look into the surface area of SUVs, vans, and pickup trucks, they are much larger than your smaller cars. Furthermore, the roofs of larger vehicles aren’t bent much like sedans and hatchbacks. In an automobile, the airflow goes from the ceiling, into the rear window, and down to the trunk.
As such, smaller vehicles have roofs that can handle the drag force without any modification. Additionally, roof ridges also eat away a centimeter or two of the vehicle’s headroom. When fabricating the roof of SUVs and vans, they need to make them a bit thicker, so they can perform proper stamping techniques.
SUVs have ridges on the roof because they help keep it more rigid and structurally sound. These small channels also make the vehicle more aerodynamic and enable it to withstand the drag force better. Overall, these ridges are quite necessary for most SUVs because they help the car perform better and make it safer.
Why do car manufacturers still keep using roof ridges on large vehicles?
There is a saying that if it isn’t broken, don’t fix it. Automakers know that adding roof ridges makes the roof stronger. These channels also allow the ceiling to carry a lot of load without collapsing the door panels and body of the car from the whole weight above.
Are there any uses for roof seams, aside from what is already mentioned?
Some roof ridges have small slits where you can attach a small hook into. If you have a roof rack on top of your car, you can use the roof ridges to fix your hooks and help secure your cargo with ropes. However, this is not quite advisable as the hooks can scratch the paint off your roof.
My SUV has a sunroof, does it also have roof ridges?
A few SUVs also have ridges on their roof despite having a sunroof in the middle. The hard part about sunroofs is that water stored on the seams can potentially enter your car when you open it. As such, prevent opening your sunroof right after the rain.