To overlap roof tiles correctly for effective weatherproofing, you need to position each tile so that it covers a specific portion of the tile immediately below it in the course and also the tile beside it. The key to this overlap is ensuring the proper measurements are maintained according to the tile type, size, and the pitch of your roof.
Based on standard practice and relevant information:
Your tiles should overlap one another by between 75mm and 100mm, depending upon their size as well as the pitch of your roof. This overlap is crucial for channeling water down the roof and preventing leaks.
Understanding Roof Tile Overlap
The overlap dimension dictates how much of the lower tile is covered by the upper tile. A sufficient overlap ensures that water runs off the surface without being driven up underneath the tiles by wind.
- Minimum Overlap: Generally, a minimum overlap is required, often specified by the tile manufacturer and building codes. The reference provides a range of 75mm.
- Maximum Overlap: While more overlap improves weatherproofing, it also means you need more tiles per square meter. The reference suggests up to 100mm.
Factors Influencing Overlap
The required overlap isn't a one-size-fits-all measurement. The reference highlights two primary factors:
- Tile Size: Larger tiles might require a different overlap compared to smaller tiles.
- Roof Pitch: Steeper roofs naturally shed water faster, potentially allowing for a smaller overlap. Lower pitched roofs require a greater overlap to prevent water ingress, especially during heavy rain or high winds.
Always consult the tile manufacturer's guidelines and local building codes for specific requirements based on your chosen tile and roof pitch.
Overlap and Batten Gauge
The tile overlap directly determines the gauge of your roofing battens. The gauge is the exposed length of the tile, which is the distance between the top edge of one batten and the top edge of the batten immediately below it.
According to the reference:
This should mean that the gauge of your roofing battens will be around 32-35cm, measuring from the top of one batten to the top of the one below it.
Getting the batten gauge right is critical because it sets the position for each course of tiles, ensuring the correct overlap is achieved consistently across the roof.
Key Overlap & Batten Gauge Information
| Aspect | Measurement / Range | Notes |
|---|---|---|
| Tile Overlap | 75mm - 100mm | Amount upper tile covers lower tile. Depends on tile size & roof pitch. |
| Batten Gauge | 32cm - 35cm | Distance between batten tops. Directly related to tile overlap. |
Practical Insight
Installing roof tiles correctly involves starting at the bottom edge (eaves) and working your way up towards the ridge, typically from one side to the other. Each tile in a course must overlap the tile next to it horizontally, and each course must overlap the course below it vertically by the specified amount (75mm-100mm vertical overlap). This vertical overlap is controlled by the precise spacing (gauge) of the horizontal roofing battens (32-35cm gauge).
Ensuring the correct overlap is a fundamental step in the roof tiling process, vital for creating a durable and weather-resistant roof covering.
