Common Parapet Wall Damages and How to Fix Them
Parapet walls are
extensions of building walls that rise above the roofline. These walls serve multiple purposes, including
protecting the roof from water, enhancing the aesthetic appeal of the building, and ensuring safety by
preventing people from accidentally falling off the roof.
However, as parapet walls are exposed to extreme weather conditions, they can suffer from various types of
damage. Understanding these common damages and how to fix them is crucial for maintaining the structural
integrity and safety of a building. If you're wondering whether parapet walls are a good choice for your
property, you can check
out our guide on this for more insights.
Parapet Wall Damage and Ways to Fix Them
Common parapet wall damages that you might notice include:Water Infiltration
Water stains on interior walls, efflorescence (white salt deposits) on the exterior, and damp patches on the parapet wall are common indicators of water infiltration.Causes: Parapet walls are highly susceptible to water infiltration due to their exposure to rain, snow, and ice. Poorly installed or deteriorated flashing, coping, and sealants can allow water to seep into the wall.
Solution: Identify and repair the source of water infiltration. This may involve replacing damaged flashing, resealing joints, and installing new coping stones with proper overhangs and drip edges.
Cracking
Visible cracks on the surface of the parapet wall, both vertical and horizontal, are clear signs of this damage.Causes: Cracking can occur due to thermal expansion and contraction, settling of the building, or the freeze-thaw cycle. Poor construction practices and the use of substandard materials can also lead to this issue.
Solution: Small cracks can be repaired using a flexible masonry sealant that accommodates movement. For larger cracks, it may be necessary to cut out and replace the affected sections of brick or stone and repoint the mortar joints. It’s also important to address any underlying structural issues causing the cracks. Take professional help to fix these damages and achieve the best results.
Spalling
Chipped, flaking, or crumbling surface material on the parapet wall is a sign that your concrete is experiencing water damage.Causes: Spalling happens when water penetrates the surface of the brick or concrete parapet and freezes, causing the material to crack and flake off. It can also occur due to the rusting of embedded metal like rebar.
Solution: Remove all loose and damaged material from the surface of the parapet wall. Repair the wall using compatible repair mortar or concrete patching compound. For significant spalling, consider replacing the damaged sections of the wall. Ensure proper drainage and waterproofing to prevent future spalling.
Deteriorated Mortar Joints
Loose or missing mortar, gaps between bricks or stones, and visible deterioration of the mortar also lead to extensive issues in the parapet wall structure.Causes: The mortar between bricks or stones in a parapet wall can deteriorate over time due to weathering and the effects of water infiltration.
Solution: Repointing is the primary method for repairing deteriorated mortar joints. This involves removing the old, damaged mortar and replacing it with new mortar that matches the original in composition and appearance. The key to a long-lasting repair is using the right methods for joint preparation and application.
Displacement
Misaligned bricks or stones, bulging of the wall, and separation from the main structure.Causes: Displacement of parapet walls can occur due to structural movement of the building, wind loads, or inadequate anchoring of the parapet wall.
Solution: Stabilizing a displaced parapet wall can involve various techniques, depending on the extent of the displacement. Minor displacements can be corrected by resetting and repointing the affected bricks or stones. For more severe cases, it may be necessary to install additional anchors or braces to secure the parapet wall to the main structure. In extreme cases, partial or complete reconstruction of the parapet wall may be required.
Vegetation Growth
The presence of plants or moss growing on the parapet wall can also lead to potential damage to your parapet walls.Causes: Seeds can settle in cracks and gaps in the parapet wall, and with moisture, they can germinate and grow, causing further damage as roots penetrate and expand the cracks.
Solution: Remove all vegetation from the parapet wall, including roots. Clean and repair any cracks or gaps where vegetation was growing. Apply herbicide if necessary to prevent regrowth. Ensure proper maintenance to prevent future vegetation growth.
