The sunroof is a great feature to have in a vehicle. It allows you to enjoy the sun and view of the sky while driving. However, what about when you have a lot of cargo to carry; can you put a cargo bag on a sunroof?
Technically, the answer is yes, but we wouldn’t recommend it. Almost all roof bag manufacturers don’t recommend it because the glass is too weak to handle the pressure from the roof bag’s weight, and it will eventually break.
In this article, we will go into more detail about why you shouldn’t put your cargo bag on a sunroof and provide the best solutions for carrying your items.
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Can You Put A Cargo Bag On A Sunroof? NO! Here’s Why
Cargo bags were designed to go on top of a car with a flat, metal roof. Depending on how much weight you put on it, placing a cargo bag directly on your car’s sunroof is a bad idea.
On average, most vehicles without sunroofs can handle a maximum weight between 165 lbs to 180 lbs on the rooftop, depending on the type of car. 
But not for the car with a sunroof. So, how much weight can a sunroof hold?
There is no specific guideline on how much weight you can put on it. From a structural load perspective, you would probably be fine. But, many are against it.
A car sunroof is a thick reinforced glass designed to be part of the load-bearing body of the car. It can take a lot of punishment in a rollover or crush.
When there is added weight from a cargo bag, it can affect the rails and alignment, damaging the roof mechanism.
In addition, it creates unnecessary stress on the hinges and seals of your sunroof, which may cause it to break or leak in the future.
If you are driving on undulated roads, one hard bump could cause any heavy object in your cargo bag to come crashing down on the moonroof, shattering it.
It’s tempered glass. Once it fails, it fails big time. Normally by raining down glass chunks on your head. Sunroof replacement is very expensive. I’m talking about a few thousands dollar to replace it.
Some of the car dealers won’t bother to repair it.
What Are The Best Solutions To Put A Roof Bag On A Sunroof?
There are three ways you can put a roof bag on a sunroof.
Slide The Cargo Bag To The Rear
If you drive a large car with a fixed sunroof, there is a bit of space to the rear of the sunroof. So you can slide the rear rail back and tie the straps to the bag.
Packing your heavy items towards the rear minimizes the sunroof’s contact area. However, it would be best to pack light items of less than 40 lbs to reduce the chance of damaging your sunroof should there be movement from the bag while you are driving.
But the problem with this method is that some of the parts of the roof bag will still be resting on the sunroof. And, you should be concerned with the wind flapping the bag against the roof and damaging the sunroof and paint.
Use A Roof Basket
A roof basket is a great way to carry your cargo bag and utilize your car’s crossbars. It is easy to assemble and install to your roof rack with a couple of bolts.
The roof basket will protect your sunroof from direct contact with the cargo bag. It also gives you more space to store larger and heavier items.
And, you can still open or tilt your car’s sunroof and enjoy the trip. The downside of a roof basket is that it creates noise and wind drag, slightly reducing your car’s fuel efficiency.
Click here to learn how to stop wind noise from the roof rack.
The price range of roof baskets is between $100 to $350, depending on the size and brand.
DIY Roof Rack
There is another option if you are on a very tight budget or don’t want to spend money on a roof rack.
If you are comfortable with tools and are a DIY person, why not make a roof rack yourself?
This option is not for everyone as it requires some technical skills. It will take some effort and time, but it can be done.
But, if you are up for the challenge, here are some instructions on how to make a roof rack.
- You need two pieces of 1×1 sheet of plywood, quality felt strips, short wood screws, short bolts, washers, gorilla glue, rubber paint, and Velcro strips.
- Cut the plywood wide enough that it doesn’t overhang the car but goes under the roof rails.
- Make sure it goes right under the roof rails.
- Drill out the plywood with a small paddle about 1.5 x 1.5 inches from each corner of the plywood.
- Screw the plywood to the 1x1s. Make sure your screws don’t go through the bottom of the 1x1s.
- Paint the rubber paint on all the wood surfaces (and on top of screws). It will make it nice looking but waterproof and resist damaging the vehicle.
- After the paint dries, glue felt strips to the bottom of the 1x1s.
- Cut small bolt-size holes in the Velcro.
- Run bolt top through the washer, the rough side of Velcro (rough side face down), and the plywood hole.
- Afterward, run smooth side through the bottom of the bolt, then the washer fastens with the nut.
- Velcro all four holes to the plywood in this fashion, then Velcro to the roof rails.
- Stick the cargo bag on the new roof rack, and it’s done! Congratulation to yourself!
The Long-Term Option: Invest In Cargo Box
We have discussed temporary methods to put a roof bag on a sunroof. But, of course, there are many other ways you can do to haul a cargo bag onto your car’s rooftop.
But, if you often go on road trips and carry a lot of stuff, investing in a cargo box would be the best option.
A roof box is a lot more expensive than the methods above, but it has some significant advantages.
- It is more aerodynamic than a roof bag. As a result, it will not flap in the wind and create noise or drag, reducing your car’s fuel efficiency.
- A good quality cargo box is durable and can last for years with proper care. And you don’t have to worry about damaging your sunroof.
- Most of them come with a lock, so you don’t have to worry about stealing your belongings while away from the car. Whereas a cargo bag is easily cut through with a knife.
- Roof boxes are watertight. You will feel peace of mind knowing that your items are safe from rain and elements.
- They look cool on your car!
The primary cons of the roof box are the price. They are not cheap, ranging from $200 to $1500 depending on size and brand.
For further reading, we’ve covered more details comparing roof bags vs. cargo boxes. You may want to check it out.
What Are The Best Cargo Bags For A Car With A Sunroof?
Now that we’ve answered the question, “can you put a roof bag on a sunroof?” it’s time to help you choose the best cargo bags for your needs.
Here are our top picks:
RoofBag Rooftop Cargo Carrier Bag (Most popular!)
Check out the best rooftop cargo bag article, where we compare and review these (and other) products in detail.
So Should You Use A Roof Bag With A Sunroof?
There are many ways to put a roof bag on a sunroof, and we have discussed some of the most popular methods. With a sunroof, it is better to use designated accessories like a roof basket or crossbars to avoid damage to your car’s sunroof.
You can also DIY a roof rack to put the bag on top of your car if you’re tight on budget.
Of course, if you often go on road trips and carry a lot of stuff, investing in a cargo box would be the best option. It is more expensive than the roof bag, but it has some significant advantages, including better aerodynamics, durability, and security.
Happy road trip!
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