Concrete or clay tiles – broken mortar under tiles

Mortar is cracked, loose or missing under ridge, hip or verge tiles

Causes

Building movement (wind, earthquake)

Poorly compacted mortar

Inadequately fixed ridge, hip or verge tiles

Common

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.