Masonry repair is a vital component of maintaining brick buildings. It’s important to catch problems early on before they become larger and more expensive to resolve.
Bulging or protruding bricks are often caused by moisture intrusion behind the wall. A mason will re-point the damaged areas with specialist mortars and reinstate the weathering function of stone faces as far as possible.
Spalling
When brick masonry deteriorates to the point that chunks of it start falling off a structure it’s called spalling. It can be caused by freeze-thaw cycles but it can also be caused by other factors like acid rain (which contains nitric and carbonic acids), pollution, poor mortar mixing and construction, wide temperature changes, and even water infiltration from leaking windows or chimneys.
The first step in repairing spalling brick is to locate the source of moisture. Often the source can be found by inspecting the entire wall for a spongy texture or bare areas of brick that aren’t supported by surrounding mortar. Fixing any leaks should be the next priority as well as sealing the brick with a breathable sealer to prevent further damage.
If the spalling is severe it might be necessary to replace the affected bricks rather than repairing them. In these cases the original brick should be removed and replaced with a similar sized piece, matching the masonry style as close as possible. A mason can use items like forks to add character marks to the replacement brick and a trowel to smooth out rough surfaces.
Preventing spalling is a good idea by removing organic growth from the brick surface, checking sprinklers to make sure they aren’t directed at foundation brickwork, installing gutters to divert water away from masonry structures and using a breathable sealer rather than plastic ones. Installing a dehumidifier in basements is also a good idea to control moisture levels.
Cracks
Cracks in masonry walls can indicate structural damage, but they are often not as serious as they seem. The first step in repairing them is to determine what the cracks are and where they are affecting your building.
Most cracks are caused by movements that cannot be fully accommodated by the masonry construction materials. These can be due to thermal expansion and contraction, shrinkage from moisture change or cyclic movement in soils. Some of these movements are reversible, but others are permanent.
It is very important that the causing movements are identified and assessed by a qualified engineer to avoid structural failure. This is particularly important where the cracks are near beams supporting masonry walls or retaining structures. Cracks in these areas can indicate a loss of bearing capacity, requiring the structural design to be reworked.
Cracks that extend into the mortar joints of a wall are also likely to need attention. This type of crack usually indicates a stress distribution problem within the bricks themselves. This is usually due to a lack of mortar, resulting in uneven pressure on the bricks. This can be repaired by cleaning the crack and removing any debris, such as sand or silt that has accumulated. This will make it easier for the patching material to cling to the surface and hold the crack together.
Displacement
Masonry constructions are incredibly durable and long-lasting, but they do eventually require upkeep. The value of a building may be impacted if bricks and masonry begin to degrade and show signs of wear and tear, and this can make the property unattractive or less welcoming. Moreover, leaks and dampness can be a serious problem that can damage the interior walls and other materials. A professional masonry repair expert will be able to identify and fix any problems in the brickwork before they become too severe.
Displacement in masonry occurs when the bricks begin to shift or change position, and this can cause a lot of damage and is usually a sign of structural instability. It is usually caused by the loss of support or by water penetration, which causes the bricks to expand. If left unchecked, this can lead to the collapse of a wall or structure.
Displacement can also be a sign of a leak in the building, and this is another reason why it is important to get masonry work done as soon as possible. Masonry experts can identify and fix any problems in the brickwork, such as tears in mortar joints or cracks in the bricks, before they cause water damage to the rest of the building. This will help to prevent costly repairs and maintain the integrity of the building.
Roots
Biological growth of algae, fungi and higher plants (vines, bushes, trees) can have an aesthetically displeasing look on a masonry building. It also has the ability to cause concerning damage to a masonry structure. This is especially true when the fungi build up and discoloration are a result of moisture that has nowhere to exit the building. This moisture can be a sign of ineffective water runoff, poor pointing or damaged masonry allowing the building to become damp.
During times of drought trees have a strong need to find water. This drives them to spread their roots in search of it. The roots can displace concrete and masonry. They can crack stone, break joints and even dislodge brick. When these root displacements occur they can create tremendous amounts of energy that are released upward. This energy can push a concrete column out of plumb, tilt a brick column or crack and displace sidewalk paving.
The best way to combat this issue is to perform routine maintenance such as tuck pointing and mortar repair on a regular basis, or at least annually. These routine maintenance activities will help prevent the destabilization of mortar and concrete joints and reduce the impact of invasive root growth. It is also important to hire a contractor that has an interest, knowledge and understanding of historic building principles and how these principles are applied to masonry buildings.