Rising damp is a common problem that homeowners face. It is caused when water rises from the ground or through walls to higher levels in a building. This can cause damage to the walls, paint, and plaster. If left untreated, it can lead to structural damage and health problems. In this article, we will discuss how to identify and treat rising damp.
What Causes Rising Damp?
Rising damp occurs when ground moisture rises through a building’s walls by capillary action. This can happen due to several reasons:
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Absorptive building materials: Building materials such as bricks, stones, and mortar are naturally absorbent. They tend to absorb moisture from the ground and retain it for a long time.
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Lack of damp proof course: A damp proof course (DPC) is a barrier that is usually installed at the base of a building’s walls. It prevents moisture from the ground from rising up into the walls. If a building does not have a DPC or if the DPC is damaged, rising damp can occur.
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Bridged DPC: A DPC can also be bridged due to external factors such as external render finishes above the DPC or high external ground levels which can create a platform for the water to ascend.
How to Identify Rising Damp?
Identifying rising damp is not difficult. Some common signs of rising damp include:
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Damp patches on walls or ceilings, which are typically darker at the bottom, traceable to the ground or measured from a common dado height.
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Peeling wallpaper or paint: As the moisture rises, it can lift and detach wallpaper or paint.
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Rotting skirting boards: The lower section of timber skirting boards close to the floor is one of the places where water tends to concentrate and penetrate.
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White salt marks: Rising damp carries salt and minerals with it, which can accumulate on walls resulting in white efflorescent salts.
How to Treat Rising Damp?
Treating rising damp involves a multi-stage process. It depends on the extent and severity of the problem. These stages include:
Identifying the root cause
The first step in treating rising damp is to identify the root cause. This involves identifying the source of the damp and addressing it. The cause can be determined by inspecting the level of damage and any visible signs such as moisture or mould.
Installing a damp proof course
If the building does not have a DPC, installing one is necessary. This involves:
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Cutting into the walls above ground level.
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Installing a specific DPC material into the wall.
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Finishing the wall to match its original look.
Removing the damaged plaster
Where the plaster is damaged, it should be removed. This involves chiselling away the damaged plaster to bare brick. This will allow the wall to dry before replacing it with a new patch or re-plastering.
Drying out the affected areas
Drying out the affected areas is crucial in treating rising damp. This can be achieved by:
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Reducing humidity levels by increasing ventilation or effectively using a dehumidifier.
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Installing drying equipment such as fans and heaters.
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Waiting for the building to dry naturally, which can take several weeks or months depending on the severity of the rising damp.
Replastering
If the wall was removed to bare brick, it will be necessary to replaster, using a salt-resistant mixture.
Frequently Asked Questions (FAQs)
Can rising damp cause health problems?
Yes. Rising damp can create an environment for mould growth. This can cause a range of health problems such as difficulty breathing, allergies, and infections.
How long does it take to treat rising damp?
The duration of treatment depends on how severe the damp is and the extent of any structural damage. Treatment can last from several weeks to several months.
Can rising damp be prevented?
Yes. Preventing rising damp involves several measures such as installing a damp proof course during construction and ensuring good ventilation.
Conclusion
Rising damp is a common problem that can be treated through a variety of techniques. It is crucial to identify the root cause of the rising damp to implement the correct treatment. Failure to treat rising damp can lead to structural damage, health problems, and ongoing Maintenance costs. By following the recommended techniques, homeowners can easily and efficiently treat rising damp in their homes.