Spalling Bricks Explained

Water is the most common cause of spalled bricks. Absorption and moisture contribute to the decay of the brick and surrounding masonry. Not every brick is made from the same materials. The main materials used in bricks are clay, concrete, and sand. They may also contain iron oxide, lime, and magnesia.

Bricks containing concrete are ideal for interior structures but have a porous surface. They are more likely to trap moisture and spall when used in external walls. Clay bricks, on the other hand, are less porous.

When the water becomes trapped in bricks, this can cause freeze-thaw cycles. When exposed to freezing temperatures, the water damage increases. This can result in rapid deterioration and costly repair work.

Efflorescence occurs when there is exposure to salt. It can form quickly in bricks made from porous materials such as concrete. However, efflorescence is likely to happen over time with bricks that are exposed to the weather, especially rain and snow.

Efflorescence is easily visible as it appears as a grey or white powder on bricks. If you come across any efflorescence on your brickwork, you will need a specialist to repair or replace the spalled bricks.

Protective coats of masonry paint are essential when dealing with properties in busy areas. This includes cities and main roads. Traffic pollution can contribute to the speedy decay of unprotected bricks due to the levels of nitric acid.

The damage caused by pollution tends to be visible. In severe cases, this can create cracks which encourages moisture absorption. This can then generate movement and warping, causing damage to the bricks and surrounding masonry.

Incorrect pointing or repointing can accelerate spalling in bricks. The bricks in question have lime mortar applied and any uneven surfaces are sanded down. The lime mortar will reinforce the brick and help prevent any flaking or crumbling.

There are some cases where cement pointing can lead to spalling. Lime mortar cannot be applied to every material such as concrete. If this occurs, it can cause major problems as the concrete will encourage the lime mortar to absorb all moisture.

Spalled brickwork may cause mould which can lead to major health risks. If your bricks have absorbed too much moisture, this can seep into the masonry and result in mildew and damp.

Spalling not only affects the bricks themselves but can also spread to the surrounding masonry. This can lead to prominent cracks appearing which will let in more moisture, causing significant damage.

The worst-case scenario is that spalling can lead to structural collapses if left untreated. Depending on where the spalled brickwork is, this can be extremely dangerous. For example, if your spalling bricks are on the chimney, this can be a major hazard.

If any structural collapses occur, you must have the brickwork and masonry repaired and replaced. This can be extremely costly depending on how much damage and how many bricks have fallen.

The RICS Home Survey Level 2, also known as a Home Buyers Survey, is an intermediate survey. This is best suited for newer properties and buildings with standard construction and properties. If any spalling is found, your surveyor will include photographs in the report and a brief description.

The RICS Home Survey Level 3, also known as a Building Survey, is the most comprehensive survey available. This option is suitable for all properties but is essential for historical and listed buildings. It can also be beneficial for properties with non-standard construction.

Like the Level 2, the Level 3 report will include photographs of any spalling found. Your surveyor will include a detailed description and advice on what reparations are needed. In some cases, your surveyor may provide estimated reparation costs.