For hundreds of years, roof tiles have been protecting homes and buildings across the world, helping to keep them dry and warm. However, in order for tiles to do their job properly, they have to be installed correctly. It is good to know how this works because that will enable you to understand what might cause them to slip out of position.
In this article we are going to take a look at how roof tiles are held in place.
How Are Roof Tiles Secured in Place?
It might seem fairly simple but essentially, roof tiles are secured in place using nails and felt. In the UK, modern roofs will use two types of tiles such as plain or interlocking tiles and the type of tile used will determine how they are laid and secured in place.
For plain tiles, they have to be double-lapped which means that there are two layers of tile across the roof. Once the tiles get to the end lap, the tiles on top have to overlap the tiles below it. Along with this, when plain tiles are used, only every fourth course of tiles is secured to the roof using nails.
When interlocking or single lap tiles are used, they are laid as one layer and interlock with the tiles next to it using grooves that create a tight joint. When these tiles are installed, each tile in a specific area such as the eaves and up verges will be secured using a nail but otherwise, it is possible to use nailing patterns such as securing down every second course.
When tiling a roof, your roofer won’t necessarily secure every single tile. There is one reason why this is done and that is because it helps to have some tiles indirectly supported. This is down to the fact that it makes it easier to swap out tiles at a later date if needed, otherwise, it would make repair jobs a lot harder, time-consuming and costly.
What About the Felt?
Roofing felt is used in the construction of roofs as it creates a flat base that makes it easier to lay the tiles. Furthermore, it also helps to add an additional layer of water protection and some form of insulation.
However, roofs don’t have to have felt in between the roof and the tiles. In older properties, particularly those constructed before 1950, they wouldn’t have had felt. Instead, they would have had back pointing which is a mortar that would have been used to hold the tiles in place as well as nails.
Why Do My Roof Tiles Fall Off?
So, now you know how tiles are secured in place, you might be wondering how they fall off. For older properties that have back pointing, this can degrade over time and wear away, causing the tiles to slip out of place. Another common cause of tiles slipping out of place is corrosion of the nails. The nails are exposed to the elements and as they corrode, they weaken and can then fail, causing the tile to slip. Finally, you might find that your tiles slip out of place as a result of the weather. Heavy wind and rain can cause a problem and once one tile slips out of place, it can cause a problem for those around it.
Now you know how your tiles are held in place, you can easily understand what work is required to rectify any slipped tiles.