If you have a slate roof, you’re purchasing a home or building with a slate roof, or you’re just interested in having one installed and want to learn more about slate, you may be wondering when you need to replace slate roof tiles.
Slate roofs can easily last 100 years or longer. But, in many cases, you may need to replace a slate tile. Broken slates can be caused by impact damage from branches, hail and other debris, and just like any other type of roof, your slate roof won’t last forever.
So, how do you know when you need slate roof repairs? Get all of the information you need from this guide.
Perform Regular Visual Inspections To Look For Cracks And Damage
The preferred method of examining and inspecting your slate roof is to have a professional slater look at it once per year. This usually won’t take long. They will look for fallen tiles (which could indicate improper installation or damage to the underlying timbers), and for cracked and damaged tiles.
In most cases, your roofing inspection won’t reveal any serious issues. But it’s always better to be safe than sorry. If a few of your tiles fail in the same area, the underlying roof structure could become sodden with moisture – and eventually require a complete roof replacement, rather than just the replacement of damaged slates.
Inspect Individual Tiles For Flaking, Delamination, Or Powdering
Want to inspect your tiles yourself? Feel free! As a rule, it’s pretty easy to identify a tile that’s faulty. Whether you’re looking at fallen tiles, or you’re willing to get up on your roof (be safe!) to look at your own slate tiles, you’ll want to look for:
- Flaking – Excessive flaking (small bits of stone removed from the edges of the slate) can indicate a low-quality slate stone. It may also indicate severe weathering. In some cases, a sealer may help prevent further flaking, but it’s usually better to replace the affected tile.
- Delamination – If it seems that one or more layers of the tile are “peeling” and pulling away from each other, this indicates that the slate has absorbed quite a bit of moisture, usually from the edges. This causes swelling inside the slate, especially during freeze-thaw cycles, and will result in the destruction of the tile. Tiles that exhibit delamination must be replaced.
- Powdering on the underside of the slate – This is known as “efflorescence,” and is composed of dissolved salts after water evaporates. This is not a normal thing to see in slate tiles, unless there is water leaking underneath the slate and pooling. Defective roof flashing often causes this – so the fault may not be with the slate tile, but you still need to have your roof inspected professionally ASAP.
- Sliding slate – If you notice one or more slates that have “slid” and appear to be slightly out of line compared to other slates, this indicates the failure of one or more roofing nails. These slates will need to be removed and properly re-installed to ensure they do not “slide” and expose the roof structure to moisture and the elements.
If you’re not sure if you can recognize these signs that there may be something wrong with your slate tile, we recommend turning to a professional.
Know When You Need To Repair Your Roof (And When It Needs To Be Replaced)
Slate is one of the most forgiving roofing materials on the market. Usually, a slate roof requires replacement, it’s not due to the slate wearing out, but due to moisture leaks causing damage to the underlying roofing structure.
In most cases, when only some of your roof tiles are damaged, you’ll simply be able to replace them, after you ensure that the underlying structure is in good shape.
However, if the number of damaged tiles on your roof is 20-30% or more of the total number of tiles, it may be time to consider roof replacement. You will be able to re-use most of your tiles, but such widespread damage to the slate tiles indicates that the roof has been neglected – and that the underlying structure is almost certainly leaky and faulty.
Need Help? Contact NSW Slate Roofing
At NSW Slate Roofing, we’re experts in every aspect of slate roof inspection, repair, and replacement. If you have a slate roof, and are not sure where to start when it comes to repairs and inspections, we’re here to help. We are experts in all types of slate including Welsh Slate and Composite slate. Schedule an appointment with our team today! Call us on 1300 102 908.