Replacing individual slates or tiles that have cracked, slipped or blown off, rather than touching the rest of the roof. Slates are held by nails that eventually corrode, which is why old slate roofs shed one here and one there over time. Concrete and clay tiles usually go through frost damage or from being walked on. We match the replacement to what's already up there on colour, profile and size, so the repair blends in instead of leaving a patch that catches the eye from the street.