Concrete tile roof installed 18 months ago. Two broken tiles; no weather issues (hail or high winds)to cause this, nor has anyone walked on the roof. May have happened when large amount of snow collected on roof and slid off a few days later. Called the tile manufacturer (Boral); they state it is not the product likely roof was installed incorrectly (frost, ice under the tiles). Called the owner of the roofing co (not a fly by night company); he stated that this is a repair and will cost min of $350 to fix, he believes the product is defective. I asked him to honor his 10 year warranty on the installation or to send me a statement with his belief that the product is defective (so I can provide to manufacturer). He has not replied. Cost of roof was $38k.