Arch & Lintel Failure

Subsidence is the top cause of arch and lintel failure. Subsidence causes the ground underneath your home to sink downwards or shift laterally. This places immense force on your home’s foundation.

The force travels throughout your home’s foundations up into your walls, ceiling and roof, causing unevenness and instability everywhere. When uneven forces find themselves around the arches and lintels above your windows and doors, they’re going to squeeze them inwards or pull away from them.

Steel arch bars or steel lintels corrode over lengthy periods of time due to exposure to moisture and salts. These arch bars and lintels are designed to divert heavy wall loads to the supports on either side of your windows and doors. However, when steel corrodes it expands, weakens and no longer diverts force properly down the sides of windows and doors. Downward pressure causes cracks to appear, bricks to slip and even fall down from above.

If an arch is poorly constructed or if a lintel is poorly installed, the pressure surrounding the arch or lintel is going to be uneven. Uneven loads will eventually cause them to break and fail.

Over time, the mortar used to hold brick or stone together can fail due to natural elements such as time and weather. Lime mortar, which is used in a lot of older buildings, is particularly susceptible to corrosion.

When the mortar used to fasten the bricks in arches together becomes weak, the bricks become loose. When mortar surrounding a lintel fails, it’s usually an indicator the mortar around the window and doorway will fail too.