A cover tile (Dutch: bovenpan) is the upper roof tile in an overlapping tile arrangement, sitting on top of the under tile (onderpan) to create a watertight roof covering. This two-layer system is characteristic of traditional pan tile roofing, where alternating concave and convex tiles channel rainwater downward.
How cover tiles work
In a pan tile roof, the under tiles (concave) are laid first in vertical rows from eaves to ridge. The cover tiles (convex) are then placed over the joints between adjacent under tiles, overlapping both sides. This interlocking arrangement creates channels that guide water down the roof surface and prevent it from penetrating at the seams.
The profile of a cover tile is typically rounded or angular, depending on the regional style. In Mediterranean and southern European architecture, semi-cylindrical cover tiles are common. In northern Europe, angular profiles are also widely used.
Materials
Cover tiles are most commonly made from:
- Clay — fired at high temperatures for durability and a traditional appearance. Available in natural red, brown, or dark glazed finishes.
- Concrete — a more affordable alternative that mimics the shape of clay tiles. Heavier but widely used in residential construction.
Both materials are weather-resistant and have a long service life, often exceeding 50 years when properly installed.
Application in construction
When laying a cover tile roof, correct overlap and alignment are critical. Each cover tile must sit firmly on the under tiles beneath it and overlap the tile below in the same row by a specified amount. Tiles near the ridge and eaves are secured with clips or mortar to resist wind uplift.
During maintenance, individual broken cover tiles can be replaced without disturbing the surrounding tiles, making this roofing system practical for long-term upkeep.
Related terms
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