- Shattering and exploding sunroofs happen once a month somewhere in the U.S.
- The reasons are unclear, but the problem has increased over time as roofs have become larger and more common.
- It is still a rare event but dangerous and may in some cases be the result of faulty materials.
Sunroofs are exploding more often, says Consumer Reports.
Once a feature limited mostly to luxury models, sunroofs have become more common in all kinds of cars and have grown larger.
But some argue material quality and safety standards have not kept up with changes in the industry, and there have been numerous incidents of sunroofs shattering for no apparent reason, Consumer Reports said in a report. They found about one incident occurs every month, and incidents occur in every region of the United States.
This is not necessarily a widespread problem; tire blowouts are more common. But it can be extremely dangerous if it happens on the road, and consumers whose roofs do shatter are often stuck paying for the repairs themselves.
The exact reasons the glass shatters are a matter of debate, the report said. It might have to do with materials, coatings applied to the glass that make it weaker, or the sheer size or shape of the glass. The large panes of glass that make up panoramic roofs on some cars may be sized and curved in ways that make them more vulnerable to impacts. One expert said the larger panes of glass may weaken more over time as the car absorbs bumps in the roads, twists in the frame, and changes in temperature.
The automaker Kia told Consumer Reports the reason glass roofs shatter is "always road debris or projectiles, even in cases involving users who insist no road debris caused the breakage."