Concrete or clay tiles – broken mortar under tiles
Mortar is cracked, loose or missing under ridge, hip or verge tiles
Causes
Listed under: finishes, tiles, concrete and cement, concrete tiles, masonry, Roof, cladding, fixings and hardware, fixings, mortar, roof cladding, concrete or clay tiles
Cause
Building movement (wind, earthquake)
Repair
- remove tiles and existing mortar; re-bed tiles in new mortar; then fix the tiles. Tiles should be fixed with hot-dip galvanised nails or screws in exposure zones B or C, and 304 or 316 stainless steel nails or screws in exposure zone D (coastal).
- All perimeter tiles must be fixed, including each tile adjacent to a ridge, verge, hip, valley or eave. For other tiles, every second tile in each row must be fixed so that each unfixed tile is interlocked with a fixed tile.
- Where new replacement tiles cannot be found, contact building recyclers. An exact colour or design match may not be possible as manufacturers often had their own designs.
Cause
Poorly compacted mortar
Repair
- remove tiles and existing mortar; re-bed tiles in new mortar; then fix the tiles. Tiles should be fixed with hot-dip galvanised nails or screws in exposure zones B or C, and 304 or 316 stainless steel nails or screws in exposure zone D (coastal).
- All perimeter tiles must be fixed, including each tile adjacent to a ridge, verge, hip, valley or eave. For other tiles, every second tile in each row must be fixed so that each unfixed tile is interlocked with a fixed tile.
- Where new replacement tiles cannot be found, contact building recyclers. An exact colour or design match may not be possible as manufacturers often had their own designs.
Cause
Inadequately fixed ridge, hip or verge tiles
Repair
- remove tiles and existing mortar; re-bed tiles in new mortar; then fix the tiles. Tiles should be fixed with hot-dip galvanised nails or screws in exposure zones B or C, and 304 or 316 stainless steel nails or screws in exposure zone D (coastal).
- All perimeter tiles must be fixed, including each tile adjacent to a ridge, verge, hip, valley or eave. For other tiles, every second tile in each row must be fixed so that each unfixed tile is interlocked with a fixed tile.
- Where new replacement tiles cannot be found, contact building recyclers. An exact colour or design match may not be possible as manufacturers often had their own designs.