Electric Vehicle Owners Dismayed By Broken and Cracked Glass Roofs

Electric vehicles have added many new features to our vehicles. Most notably, the frunk, or “front trunk.” Given the clean sheet of paper automakers are working with, new things should be part of the EV revolution. However, some owners are finding that one trend, glass roofs, may not be suitable for all vehicle types or all owners’ needs.

Related Story: Every New Vehicle Owner Convinced Their Model Has Defective Windshield Glass

What Are "Glass Roofs" On Vehicles?
The glass roofs we are referring to are not moonroofs or sunroofs. Nor are they really panoramic moonroofs or sunroofs either. Rather, we are referring to the all-glass roofs or mostly-glass roofs used on some models. The Tesla Model X was a pioneer of novel use of glass in its roof, and along with its “falcon” doors, came to be associated with the model. The Model X was unusual in that the model does not include a windshield header. The glass expands from the base of the dash up over the occupant compartment. Other vehicles that use glass roofs include the new Volkswagen ID.4, Tesla Model Y, Tesla Model S, Tesla Model 3, Jaguar I-PACE, and Ford Mustang Mach-E.

Sometimes Novel Roofs Do Make Sense
In sports cars or even sporty sedans, novel roofs can make sense. Convertibles, retractable tops, targas, T-tops, and many other types of novel roofs all enhance the enjoyment of the vehicle. However, is an all-glass roof appropriate for a sport utility vehicle, or even a crossover utility vehicle?

Could such a roof withstand the impact of a kayak being accidentally bumped down on the glass while loading? Perhaps. What about the forks or pedals of a mountain bike? Unlikely. And can such roofs happily coexist with aftermarket cargo bars or cargo bags? Why would anyone assume so?

Update: Chevrolet Follows Glass Roof Craze With Upcoming Silverado Electric Pickup

Do Glass Roofs Break With No Known Cause?
One Ford Mustang Mach-E owner reported in the MachEForum that the glass roof was damaged with no known impact. The owner didn’t hear anything hit the roof. Tesla vehicle owners have also had roofs break without any clear explanation why. A Model 3 owner reported that the glass roof of the sedan was broken, but not from the outside, the inside.

Why Do Glass Roofs Break?
Some of the broken roofs seem to have occurred from undetectable causes. Conversely, reports of glass roofs surviving severe hail storms are common. When the breaks occur, some owners find the part is not available. Such as one EV owner in a popular forum who reported waiting 20 weeks for a glass roof replacement. The owner of the EV who provided us with images of the broken roof shown here was told the replacement would be a one-week wait. That seems more reasonable given that the vehicle is driveable.

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Multiple Broken Glass Roofs On One Car
It would be easy to dismiss glass roof breaks by wishing they were a very rare occurrence, but one EV owner has had two glass roofs break. He has a first and second Youtube video showing the breaks and detailing how it was resolved.

Is A Broken Glass Roof Covered By Warranty?
One clear trend from the owner posts we’ve read is that manufacturers do not consider the glass roof part of their warranty program for repair after the vehicle has been delivered and inspected by the new owner. This was true for one owner who had a glass roof panel actually fly off the vehicle. The manufacturer was forced to recall that model for unsafe glass roof panels. Following this, one would expect that the manufacturer would change its quality control to ensure its roofs were well secured, but an owner of a newer model from that same brand reported that the glass roof flew off on the drive home from the vehicle’s delivery appointment. NHTSA has also recalled that model’s roof due to safety issues.

UPDATE! - Ford Recalls Mustang Mach-E for Glass Roof Defect

Are Broken Roofs Just an Electric Vehicle Thing?
Although we have used multiple EV examples in this story, it is not the opinion of the writer that electric vehicles’ roofs are in any way less robust than glass roofs found on other vehicles. Rather, Tesla and Ford are just ahead of the curve. Glass moonroofs and sunroofs have been "exploding" for decades. The image above is a Honda Accord's moonroof. With more new models following Tesla’s lead on glass roofs (and a lot of other things), we suspect more roof-related problems from more brands and models will follow.

Do Glass Roofs Ever Make Sense On Utility Vehicles?
To this recovering engineer, it seems illogical to add a roof panel that adds weight to a utility vehicle and which also makes it less resistant to damage. Yes, the style and enjoyment of a vehicle matter. However, the Model Y, Model X, I-PACE, and Mustang Mach-E are considered crossovers by everyone and considered SUVs by many. It is this vehicle tester’s opinion that a delicate all-glass roof has no place on a utility vehicle.

Tell Us About Your Broken Roof
What’s your opinion? Tell us what you think about using large glass panels or all-glass roofs on vehicles in the comments below. If you have had a glass roof problem, please tell us about your experience so that others may benefit from your lessons learned.

Top of page image courtesy of Joan Morgan.

John Goreham is a long-time New England Motor Press Association member and recovering engineer. Following his engineering program, John also completed a marketing program at Northeastern University and worked with automotive component manufacturers. In addition to Torque News, John's work has appeared in print in dozens of American newspapers and he provides reviews to many vehicle shopping sites. You can follow John on Twitter, and view his credentials at Linkedin