Pictured are just a few of the hundreds of chips on this tile roof. What is different about these chips is the small round aggregate / impurity seen directly in the middle of almost every chip. In the manufacturing process the aggregates are randomly distributed throughout the body of the tile. Some of these aggregates end up extremely close to the surface of the tiles and they make the tile very susceptible to chipping.
If anything were to strike the tile directly on top of the location where the aggregate is seated then the result would likely be a chip with the aggregate subsequently exposed and centered in the middle of the chip.
Under normal weather conditions the locations of these aggregates would never be impacted by anything strong enough to cause them to chip. However in a hail storm thousands of hailstones will impact nearly every single square inch of the roof surface. It is inevitable that hail stones will find their way to these susceptible areas of the roof system.
The result is potentially hundreds or even thousands of small chips directly over the location of the aggregates.
Some insurance carriers have hired engineering firms that have attempted to convince consumers that these chips were caused due to expansion and contraction of the aggregates and that the fresh chips that we are observing all just happened to occur just before the hail storm.
The problem with this theory of course is that in the areas of the roof where trees or other obstructions block the roof from hail impacts – there are no chips. In areas just down the street where the hail did not strike – the roofs have no chips. On the slopes of the roof facing the direction from which the hail was falling – there were many more chips.