Slate roofs add an elegance to the architectural design of a house.
Despite being more expensive, it is a very popular roofing material due to its distinct character and imperious durability.
The durability of a slate roof makes it a brilliant match for solar panels. Both are built to last for decades, 40 years or longer in many cases.
If you’re reading this then you’re probably wondering if you can install solar panels on a slate roof?
The good news is yes! It’s absolutely possible although it can be a little more tricky compared to other materials.
While slate is very long lasting, when working on this type of roof you need to be a little careful as you don’t want to knock off or crack the tiles.
When it comes to solar panels there will be drilling involved so there’s several factors you need to consider during installation.
Solar Panel Installation on a Slate Roof
The method of installing solar panels on a slate roof is very similar to other materials like shingle asphalt. The mounts need to be drilled and fixed to the roof support beams.
That being said, things are a little more complicated with slate tiles as you can’t drill directly through this material. To fix the mount, first you need to remove a slate tile. Where you remove a tile the mounting system is installed to the sheathing.
There are a few different mounting systems. Usually, a metal plate is used in place of the slate tile.
Flashing is also then installed around the mount to help divert water away from the mounting area and hole.
The rest of the process is very similar to shingle roofs with correct size screws, washers, and sealant to ensure a strong waterproof finish.
As this type of material takes extra care, you should use a solar panel installer with previous experience in working with slate roofs. In some areas of the world, slate might be uncommon and installers might not be skilled or equipped for this type of work.
How to Install Solar Panel Mounts on a Slate Roof
Let’s go through the step-by-step process of installing a mounting system with a slate roof.
- Remove slates where the brackets will be mounted and replace with lead flashing for a watertight finish.
- Drill and screw the brackets to the timber beam over the flashing.
- Trim the original slates to fit around the bracket and install back over the flashing.
- Add another lead flashing over the top side of the bracket to ensure a waterproof finish around the mount.
- Trim and replace the top slate tiles over the flashing.
- Fit the solar panels to the mounts.
Here’s a video walk-though for you to watch:
What to Avoid When Fixing Solar Panels to Slate Roof
The number 1 thing to avoid with slate is drilling!
You or the installer should never try to drill into the slate as it will lead to cracking and smashing of tiles. And slate is expensive to replace. Even if it doesn’t completely smash and fall apart, you will be left with cracks which ruin the waterproofing. Adding to this, it will usually void any roof warranties.
Benefits of Solar Panels on a Slate Roof
Yes it is more tricky to mount solar panels on a slate roof. But there are useful benefits to mixing the two.
- Slate is incredibly durable and can easily last 50 years (and much more!). This is because it is extremely waterproof and reduces build up of mould or fungus. That’s ideal for solar panels which should last at least 25 years and perform best when clean.
- If you live in an area with variable weather the slate won’t have an issue in fending off the elements including temperature changes, rain, snow, and wind. This reduced need for maintenance means you won’t have to worry about accessing areas for repairs covered by the solar panels. In fact, solar panels will add even more protection.
- If you’re adding solar panels because you’re eco conscious then slate fits this ideology. It is a naturally occurring stone which rarely needs replacing, helping to further reduce your impact on the planet.
Final Words for Solar Panels on a Slate Roof
As you can see it is perfectly possible to install solar panels on a slate roof.
The material actually makes a durable base for your array.
It will require a little more care and expense to complete the job but this should not put you off.
Certainly, don’t try to cut corners, and make sure you use the correct mounting systems to keep your slate in one piece.
And remember, don’t drill into slate. Instead replace tiles with metal plates and flashing for a waterproof finish.
