Medium or high profile tile should have headwall flashing made of lead that can be bent to conform to the tile profile, or conventional headwall flashing that has a closure of some type installed to prevent wind-driven rain from entering beneath the lower flange.
The type of sidewall flashing used depends on the tile profile”
Flat tile should have step flashing in most parts of the US. In areas designated “high-wind”, local jurisdictions may require continuous flashing.
Medium and high profile
Medium and high profile tile will typically be installed with continuous sidewall flashing that has a water channel built in that will prevent runoff from entering beneath the tile.
Penetrations like plumbing stack vents, combustion vents, and roof vents (attic ventilation devices) may be flashed at both the underlayment level and at the surface of the tile in a manner in which the uphill flange is installed beneath tile and the downhill flange is installed on top or the tile. The flashing flanges should fit the contours of the tile profile. Other flashing types may be used but should keep runoff on top of the tile. Leaving a gap around the penetration and filling it with mortar is sometimes common, but is poor practice.