There’s nothing I love more than the look of a vehicle with a panoramic sunroof. Whether you’re looking at the new Mercedes-Benz C-Class or the more lowly Kia Optima, vehicles equipped with full black tinted glass roofs simply look the business. I especially like the contrast between the dark roof and lighter paint colours, such as a beautiful snow white-pearl or light silver metallic.
Most people would tend to agree with how good they look, but having owned a panoramic sunroof equipped vehicle for the past 3 years or so, I feel there are some important issues which new car buyers need to know about before ticking that box on the options list.
1. Increased heat entering the vehicle
This might seem obvious, but a panoramic sunroof creates a massive window (literally) through which heat from the sun can enter your vehicle. The severity of this issue depends on your location in the world, how hot the summer temperatures are and also the clearness of the sky, which has an effect on the strength of the sunlight. Here in Australia, we regularly see summer daytime temperatures in excess of 40c (104f), with crystal clear blue skies allowing the strength of the sun to reach simply murderous levels.
On days like that, leaving any vehicle (sunroof or not) out in the sun for 15 minutes or more and interior temperatures will sky-rocket, but a panoramic sunroof equipped car makes the situation even worse, with heat from the sun overhead essentially having a direct path in. You’d think tinted glass would help somewhat, but sadly it makes little difference. Tinted glass works on the principle of absorbing the heat itself instead of allowing it to pass through into the interior, essentially creating a large super-heated element across the top of your vehicle.
The retractable cloth sunshades fitted directly below the panoramic sunroof do reduce the amount heat which transfers down into the cabin, but also enables an incredible amount of heat to build up in the space in-between. This heat continues to radiate through for quite some time after you get in and start driving, meaning your vehicle’s air-conditioning system has to work a lot harder to bring the cabin back down to a comfortable temperature and then maintain that temperature.
2. Reduced headroom
You’d think that optioning a panoramic sunroof in your vehicle would give you more headroom, but usually this is not true. The additional space required for the panoramic sunroof’s motor mechanism and sunshade rollers means that your car will most likely have less headroom compared to if you went without it. Sometimes the difference can be as much as 5cm (2 in).
Retracting the sunshade or opening the sunroof itself often doesn’t fix the issue, either, as the opening itself doesn’t go far enough across in relation to where the driver’s head is located. Put simply, taller drivers would have to tilt their head on an angle towards the centre of the car in order to have their head positioned within the panoramic roof opening, clearing the headliner. The only other alternative for tall people is to recline the seat back further in an attempt to gain more headroom, but this can create ergonomic issues relating to steering wheel and pedal reach.
So if you’re rather tall, do try out the seating position in a panoramic sunroof equipped vehicle before you decide to order or purchase one. You’ve been warned!
3. Added weight where you don’t want it
Manufacturers work hard to reduce the weight of their vehicles as it pays dividends when it comes to acceleration, braking and fuel economy. Where possible, they also try to position heavy objects (such as the engine, gearbox and fuel tank) as low down in the vehicle as possible, in order to improve vehicle stability and handling.
It doesn’t take a rocket scientist to work out that a 100kg+ (220lb+) glass roof running across the very top of the vehicle isn’t exactly the best idea. The reason they weigh so much is due to glass being a heck of a lot thicker and heavier than steel or aluminium roof panels, not to mention all the additional reinforcing bars, electric motors and drainage channels required.
Think about it another way. Having a panoramic sunroof fitted to your vehicle is essentially the same as having an additional 100kg+ passenger in your car permanently.
4. Added complexity and noise
While it may be similar to the weight factor I mentioned above, this is an important issue to consider in its own right. Panoramic sunroofs introduce added complexity to a vehicle. Suddenly you’ve got two or more heavy glass panels; motors, channels and rollers for the sunshade; plus the main motor and sliding mechanism for the sunroof panel itself.
Aside from all being parts which could break or go wrong, they’re all positioned directly above your head, with the potential for a myriad of rattles, squeaks and flexing noises to develop and annoy the hell out of you as you drive along. It is also worth noting that raindrops hitting a glass roof are a heck of a lot louder, too.
A conventional steel/aluminium roof is not only quieter but most importantly there’s nothing hiding behind the roof lining that could rattle or break in the future.
5. Reduced structural integrity
When it comes down to it, a panoramic sunroof is essentially a giant hole in the roof of your vehicle, and while they do contribute to the structural rigidity of the vehicle, it’ll never be as good or as strong as a vehicle with a conventional roof. It is also worth considering that, by design, the rubber seals themselves are not 100% waterproof. While the rubber seals do keep the majority of the water out, panoramic sunroofs rely instead on water drainage channels within the roof of the vehicle to keep the moisture out.
These drainage points can sometimes clog, potentially causing the drainage channels to overflow and leak water into the cabin.
6. How often will you actually use it?
People often purchase convertible vehicles because they imagine they’ll get the roof down all the time, but the reality is very different. Often it is simply too hot, too cold or too windy to drive with the roof down and as a result the driver eventually stops using it. From what I’ve seen, panoramic sunroof equipped vehicles often suffer a similar fate.
Like a convertible, a panoramic sunroof by design is an ‘all or nothing’ proposition. You can’t have the sunroof open unless the internal sunshades are completely retracted, meaning the entire vehicle is open to the sun. This makes it pointless to leave the sunroof open or tilted whilst parked (in an effort to vent hot air from the vehicle) as the glass roof will let in far more heat than the sunroof can expel.
In addition, sunroofs are often too loud to have open at speeds above 80kmh (50mph), unless you enjoy yelling at your passengers in order to have a conversation.
So, would you still option a panoramic sunroof?
Despite their flaws, some vehicle owners do love their panoramic sunroofs. Perhaps they live in a more forgiving climate, or the system employed in their vehicle is better designed than the ones I have dealt with in the past. But I do know that the next time I go to purchase a vehicle, I’ll definitely save the money and go without a panoramic sunroof.
They may look fantastic and the idea of owning a vehicle with one is extremely appealing, but do consider my warning that the reality might not live up to your expectations. Think long and hard about it before you pull the trigger on that particular option.
Do you own a vehicle with a panoramic sunroof? If so, what are your thoughts?