

One of the first areas to look at is damage to any roof timbers. Look for rot caused by damp. These will have to be replaced otherwise just replacing tiles will do nothing but seal in the problem to keep getting worse.
Remember when removing the tiles or slate to be replaced to remove those from the line above as well. Work from the top downwards, and prop the top row with wooden wedges.
Start the replacement work at the bottom course. Hook each tile over the batten by its nibs, ensuring that you have lined the tile up to be exactly.
Tiles or slates that need nailing should be fixed with galvanized or aluminium alloy nails.
At the top layer using the wooden wedges lift the tiles so that the new ones can be slid underneath them.