If a fiber cement roof is properly laid, how many shingles are penetrated if a hole is drilled through it?

When a hole is drilled through a properly laid fiber cement roof, only one shingle is penetrated. This is due to the way shingles are installed in overlapping layers. Each individual shingle is designed to cover a specific area, and when applied correctly, one shingle is positioned above the next in a staggered pattern to provide optimal water drainage and protection.

Drilling through the roof typically means that the drill will pass entirely through the thickness of the single shingle that is being penetrated at that moment without affecting the underlying shingles beneath it. This design helps maintain the integrity of the roofing system since only one layer is compromised during penetration. Therefore, the answer confirms that only one shingle is successfully penetrated when drilling through a properly laid fiber cement roof.