Repairing Slate Roofs

Slate is a very durable roof tile that can last over a hundred years. Their weakness is in the nails that secure them to the roof battens. The nails can deteriorate and rust away which cause the slates to slip out of position. Slate roof tiles can be re-secured with new nails.

Slate tiles have the ability to delaminate which damages the tile and ultimately causes them to wither and crack. When this happens the roof will need replacing.

Slate roof tiles are often replaced with tiles. Tiles are heavier than slate and your roofs trusses may need reinforcing.

You may just need to replace a section of your slate roof if this is the case make sure you use a similar thickness of slate as the tiles will not fit properly if they are a different size to the existing slate tiles. Also check their color as slate is available in a variety of shades. Make sure the new slate matches the existing slate.

Copper or galvanized clout nails are used to secure slate tiles to the roof battens.

When replacing a single slate tile you will not be able to fit into the right position as the above course of tiles will not allow for this. In this case use a narrow peace of galvanized metal and fix it from the outside leaving a small piece of metal showing.

New slates do not come with drilled holes for the clout nails. Drill holes in the correct position using a 6mm masonry drill bit. Striking a thin stainless steel nail through the slate is another way of creating a hole but this may require practice.

Before making a attempt to repair a roof make sure you create a safe platform from which to work. Long double ladders are ideal to work with and can be tied together at the apex so that one ladder runs down each side of the roof.

Sometimes a quick tile replacement repair is needed to prevent rain water from penetrating and causing damage to the interior. In this case you may use aluminum or galvanized sheeting cut to the size of the slate tile until such time you are able to find a suitable replacement tile.

When cutting slate tiles work on a flat wooden board. Use a tile cutter to score a line where the tile needs to be cut. Use a flat bolster to strike along the tile until it breaks. Alternatively you may use an angle grinder with a masonry blade to cut the tile.