Common Types of Masonry Deterioration
Nov 18th, 2024
Common Types Of Masonry Deterioration
Nov 18th, 2024 2024
Masonry, made of brick, stone, or concrete, is one of the most durable building materials
available, however, over time, various environmental and structural factors can cause
deterioration which compromises its stability, aesthetics, and functionality. Understanding
common types of masonry deterioration can help in preventing and addressing these
issues early on.
1. Weathering and Erosion
available, however, over time, various environmental and structural factors can cause
deterioration which compromises its stability, aesthetics, and functionality. Understanding
common types of masonry deterioration can help in preventing and addressing these
issues early on.
1. Weathering and Erosion
Weathering and erosion are among the most common causes of masonry deterioration.
Weathering occurs when masonry materials are exposed to rain, wind, sunlight, and
temperature changes. These elements, especially when combined with freeze-thaw cycles,
can lead to gradual but significant surface wear. Erosion of masonry surfaces, often seen
as small pits or a general roughness on the stone or brick surfaces, is especially common
in areas exposed to wind-driven rain or extreme weather fluctuations. Over time, erosion
can expose the underlying structure of the masonry, making it more susceptible to further
damage.
2. Freeze-Thaw Cycles
In colder climates, the freeze-thaw cycle can be particularly damaging to masonry. When
water enters the pores of the materials and freezes, it expands, exerting pressure within the
masonry. Upon thawing, the water retreats, only to refreeze and expand again with the next
cycle. This repeated expansion and contraction weakens the material over time, causing
cracks, spalling and in some cases, the complete failure of individual masonry units. The
effects of freeze-thaw cycles are especially pronounced in masonry structures that aren’t
adequately sealed or protected from moisture penetration.
3. Efflorescence
water enters the pores of the materials and freezes, it expands, exerting pressure within the
masonry. Upon thawing, the water retreats, only to refreeze and expand again with the next
cycle. This repeated expansion and contraction weakens the material over time, causing
cracks, spalling and in some cases, the complete failure of individual masonry units. The
effects of freeze-thaw cycles are especially pronounced in masonry structures that aren’t
adequately sealed or protected from moisture penetration.
3. Efflorescence
Efflorescence is a type of deterioration marked by the appearance of white, powdery
deposits on the surface of masonry. This typically happens when water containing
dissolved salts moves through the masonry and reaches the surface. As the water
evaporates, it leaves behind the salts, creating a noticeable residue. Although
efflorescence is not typically structurally damaging, it can be unsightly and may indicate
that water is penetrating the masonry, which could lead to more serious issues over time.
4. Spalling
deposits on the surface of masonry. This typically happens when water containing
dissolved salts moves through the masonry and reaches the surface. As the water
evaporates, it leaves behind the salts, creating a noticeable residue. Although
efflorescence is not typically structurally damaging, it can be unsightly and may indicate
that water is penetrating the masonry, which could lead to more serious issues over time.
4. Spalling
Spalling occurs when the surface of the masonry breaks away in flakes or large pieces,
exposing the interior of the masonry units. This type of deterioration is often caused by
freeze-thaw cycles, as mentioned earlier, but can also result from chemical reactions, like
corrosion, physical impact, or salt crystallization. Spalling weakens the structure and
exposes it to further damage by increasing the surface area vulnerable to weathering and
other deterioration processes.
5. Cracking
exposing the interior of the masonry units. This type of deterioration is often caused by
freeze-thaw cycles, as mentioned earlier, but can also result from chemical reactions, like
corrosion, physical impact, or salt crystallization. Spalling weakens the structure and
exposes it to further damage by increasing the surface area vulnerable to weathering and
other deterioration processes.
5. Cracking
Cracks in masonry are a common form of deterioration and can result from a variety of
factors, including settlement, thermal expansion, structural loads, and seismic activity.
Small hairline cracks might not pose an immediate threat but can allow water to infiltrate
the masonry, leading to other issues like freeze-thaw damage and efflorescence. Larger
cracks, especially those that appear suddenly or widen over time, may indicate structural
problems requiring professional evaluation.
6. Biological Growth
factors, including settlement, thermal expansion, structural loads, and seismic activity.
Small hairline cracks might not pose an immediate threat but can allow water to infiltrate
the masonry, leading to other issues like freeze-thaw damage and efflorescence. Larger
cracks, especially those that appear suddenly or widen over time, may indicate structural
problems requiring professional evaluation.
6. Biological Growth
Masonry structures in damp, shaded, or humid environments are prone to biological
growth, including algae, moss, and lichen. These organisms can retain moisture on the
masonry surface, creating an environment that accelerates other types of deterioration,
such as spalling and cracking. Additionally, biological growth can lead to staining, which
affects the appearance of the structure.
7. Chemical Damage
Certain chemicals can react with masonry materials, causing deterioration. Acid rain, for
instance, can be harmful to limestone and marble due to their high calcium carbonate
content. In industrial areas, pollution can lead to chemical reactions that weaken masonry
materials, sometimes resulting in irreversible damage. Chemical exposure can also come
from de-icing salts, which can infiltrate the masonry through water penetration and lead to
spalling and cracking.
Masonry deterioration is often a result of environmental exposure, moisture infiltration, and
structural stress. While masonry is a resilient material, it requires regular maintenance to
ensure longevity. Preventative measures, such as proper waterproofing, routine
inspections, and addressing small issues before they become severe, are essential.
Understanding the signs and types of masonry deterioration can aid in early intervention,
which can save time, money, and, most importantly, preserve the structural integrity and
aesthetic value of masonry structures.
growth, including algae, moss, and lichen. These organisms can retain moisture on the
masonry surface, creating an environment that accelerates other types of deterioration,
such as spalling and cracking. Additionally, biological growth can lead to staining, which
affects the appearance of the structure.
7. Chemical Damage
Certain chemicals can react with masonry materials, causing deterioration. Acid rain, for
instance, can be harmful to limestone and marble due to their high calcium carbonate
content. In industrial areas, pollution can lead to chemical reactions that weaken masonry
materials, sometimes resulting in irreversible damage. Chemical exposure can also come
from de-icing salts, which can infiltrate the masonry through water penetration and lead to
spalling and cracking.
Masonry deterioration is often a result of environmental exposure, moisture infiltration, and
structural stress. While masonry is a resilient material, it requires regular maintenance to
ensure longevity. Preventative measures, such as proper waterproofing, routine
inspections, and addressing small issues before they become severe, are essential.
Understanding the signs and types of masonry deterioration can aid in early intervention,
which can save time, money, and, most importantly, preserve the structural integrity and
aesthetic value of masonry structures.
Written by Reba Ashby
A historic preservationist specializing in traditional masonry, architectural conservation, and building assessments.
Written by Reba Ashby
A historic preservationist specializing in traditional masonry, architectural conservation, and building assessments.