Rising damp is one of the rarer forms of damp issue, but can also be one of the most serious. If a rising damp problem is left untreated, it can cause significant damage, making it essential to identify the signs, understand what causes it, and seek appropriate treatment. In this blog, we will delve into the world of rising damp, exploring the various causes and signs to look out for whilst providing valuable insights. Whether you are a homeowner, landlord or believe you have some evidence of rising damp in your property, this blog will equip you with the knowledge you need to identify and take action. So, let’s dive in and uncover the mysteries together in our guide to rising damp.
What is rising damp?
Rising damp refers to the upward movement of moisture or water from the ground into the walls and other porous materials of a building. It is a type of damp that occurs when groundwater rises from the soil and is drawn up through capillary action, resulting in dampness and damage to the affected areas. It is often seen in older buildings with inadequate damp proofing measures or when existing damp proof courses or damp proof membranes have deteriorated over time.
Rising Damp can lead to severe issues throughout your property as the water slowly deteriorates the surrounding material, rotting timber and causing further concerns such as wet rot. It can affect the entire property, with rising damp on internal walls causing issues such as damp patches to increased mould growth and peeling, and on external walls causing staining and even crumbling.
What are the causes of rising damp?
Several factors cause rising damp, but typically it occurs at its core when groundwater enters a building’s walls and floors. Most buildings have some form of weather and water barrier installed, but these can fail over time and increase the risk of rising damp becoming a concern. Capillary action, driven by the forces of cohesion and adhesion, enables water to move upwards through building materials, such as bricks and masonry. This upward movement is facilitated when the original damp proof course (DPC), a protective barrier that prevents moisture from ascending, has failed or was absent. High ground levels above the damp course can also exacerbate rising damp, as they bridge or bypass it altogether, providing an unobstructed path for water infiltration.
In addition, inadequate ventilation and insulation can contribute to rising damp by creating conditions that encourage moisture retention and migration. Plumbing leaks, faulty drainage systems, and accumulated rainwater near the building’s foundation further amplify the risk. As a result, a combination of structural vulnerabilities, environmental factors, and maintenance oversights can collectively contribute to the onset and progression of rising damp.
Identify rising damp – What are the signs of rising damp?
If you are worried about, or notice common signs associated with rising dampness, such as damp stains or patches on walls, the following guide will help you identify the evidence of rising damp. By learning to recognise and identify the signs of rising damp in your home, you’ll be equipped to take proactive measures and ensure the long-term health and integrity of your living space
What does rising damp look like?
Tide Marks on Walls: One of the most recognisable signs of rising damp is the presence of horizontal lines or tide marks on interior walls. These marks are often darker or discoloured and occur at a consistent height above the floor. They are caused by moisture-carrying soluble salts from the ground, which are deposited as the water evaporates.
Peeling or Bubbling Paint and Wallpaper: Rising damp can lead to paint and wallpaper deterioration near the walls’ base. As moisture from the ground moves upward, it can cause the paint to blister, bubble, or peel, indicating that the wall is compromised by dampness.
Efflorescence: Efflorescence refers to the appearance of white, powdery deposits on surfaces like bricks, concrete, or plaster. Like Tide Marks, these deposits are mineral salts left behind as water evaporates. Efflorescence can be a clear indication that moisture is moving through the materials.
Rotting Skirting Boards or Woodwork: When rising damp affects wooden elements like skirting boards, floorboards, or door frames, it can lead to rotting and decay. These materials become vulnerable to fungal growth due to prolonged exposure to moisture. The presence of wet rot in your property can indicate a more significant issue.
Deterioration of Plaster and Render: Rising damp can cause plaster and render to become brittle, crack, or crumble. You might notice a degradation in the appearance and integrity of the plaster, particularly in the lower portions of walls.
Crumbling Mortar: Crumbling mortar occurs when the bond between the mortar and the bricks or masonry weakens due to prolonged exposure to moisture and can begin at the lower levels of your external walls. Crumbling mortar not only compromises the structural stability of the wall but can also exacerbate the issues associated with rising damp. It can provide additional pathways for moisture to enter the wall, perpetuating the cycle of dampness.
Can I use a damp meter?
Yes, you can use a damp meter to help detect rising damp and assess the moisture levels in walls and other surfaces. Damp meters, also known as moisture meters or moisture detectors, are handheld devices commonly used by professionals to measure the moisture content of materials such as wood, plaster, and masonry. While a damp meter can be a helpful tool, rising damp is a complex issue, and its detection and diagnosis often require a comprehensive approach. If you’re unsure about using a damp meter or interpreting the readings, it’s advisable to seek professional assistance from a damp specialist or conduct a damp survey for a thorough assessment.
Does rising damp smell?
Rising damp can often be associated with a distinctive musty odour. The smell is usually described as earthy, damp, or mouldy. This odour results from the presence of black mould or mildew, which thrive in damp environments. If you notice a persistent musty smell in your home, it could indicate rising damp or other moisture-related issues that need attention.
Can you feel rising damp with your hand?
Yes, rising damp can often be felt with your hand when you touch affected surfaces. When rising damp is present, the affected areas may feel damp to touch with a cold and clammy sensation. This is due to the moisture that has moved upward through the building materials, making them feel wet and cool.
However, it’s important to note that the ability to feel rising damp with your hand may vary depending on factors such as the severity of the issue, the type of materials involved, and the specific conditions of the environment. Other issues, such as those caused by condensation or high humidity levels, can also create a similar sensation when touched.
What does rising damp look like?
The following images demonstrate the visual appearance of the common signs of rising damp on both internal walls and external walls. These visuals serve as a guide, providing valuable insights into the recognisable signs that may indicate the presence of rising damp
Signs of rising damp on internal walls
Rising damp treatment – How can you treat rising damp
Treating rising damp typically involves a combination of preventive measures and remedial treatments. These treatment options include Damp-proof Course (DPC) installation, replastering with waterproof materials, rectifying external issues, enhancing ventilation and insulation, improving drainage and removing and replacing affected materials:
Damp-Proof Course (DPC) Installation
A new damp-proof course can be installed to create a barrier against the upward movement of moisture. This may involve the injection of a chemical DPC or inserting a physical DPC layer into the affected walls. Installing a chemical DPC involves drilling holes into afflicted walls and injecting a specialised solution to establish a moisture-resistant barrier.
Rectifying External Issues:
Remedying external factors is pivotal. Repairing damaged points, sealing gaps around windows and doors, and ameliorating drainage and ground levels that bridge the DPC collectively prevent sustained moisture ingress, complementing internal treatments.
Enhancing Ventilation and Insulation:
Enhanced ventilation and insulation in moisture-prone areas minimise condensation and dampness. Incorporating mechanical ventilation systems and dehumidifiers regulates indoor moisture levels, mitigating mould and mildew proliferation.
Improving Drainage:
Enhancing drainage systems effectively redirects water away from the building’s foundation, mitigating the risk of rising damp caused by water accumulation and preventing water from rising into the walls of the property.
Removing and Replacing Affected Materials:
Removing and replacing extensively damaged materials may be necessary. Replacing compromised elements with moisture-resistant alternatives bolsters the building’s resistance to rising damp. In severe cases, damp and damaged materials such as plaster, skirting boards, or floor coverings may need to be removed and replaced.
Professional Assessment:
Before treatment, a comprehensive assessment by a damp specialist is imperative to pinpoint the extent and root causes of rising damp. This evaluation guides the selection of tailored treatment methods, ensuring a well-rounded and efficient solution.
By integrating these multifaceted treatments, property owners can effectively combat rising damp, rejuvenating the health and longevity of their structures.
How much does it cost to fix rising damp issues?
The cost of fixing rising damp issues can vary depending on various factors, including the extent of the problem, the size of the affected area, and the chosen remedial methods. Factors such as the need for additional repairs, the type of materials involved, and any associated structural damage can influence the overall cost of resolving rising damp issues. Consult with a professional damp specialist or a qualified contractor, who can look at the situation and provide an accurate cost estimate.
Do I need a rising damp specialist or a damp survey?
Hiring a specialist for a damp survey is a clever move if you’ve noticed persistent signs of rising damp, such as damp patches, peeling paint, or a musty odour. This option is precious if you’re uncertain about the cause of the damp issue or suspect multiple moisture sources. During a rising damp survey, the surveyor will examine the affected areas, identify potential causes of dampness, and recommend appropriate solutions. This approach provides a comprehensive assessment of the situation, helping you make informed decisions based on expert analysis.
If the presence of rising damp is confirmed, enlisting the services of a rising damp specialist becomes a wise choice. These experts deeply understand the challenges posed by rising damp and possess the knowledge to implement targeted solutions. A rising damp specialist will focus on addressing the root cause of the issue, which often involves treatments such as installing a new damp-proof course, repairing damaged materials, or implementing effective drainage solutions. Their specialised expertise can ensure a thorough and effective resolution to treat the issue.
How does rising damp differ from other common damp problems?
Rising damp poses unique challenges, and confusing the signs and symptoms with other common damp problems can be easy. Often rising damp may be a combination of issues, each of which may initially be considered a more minor damp problem. A Wet Rot survey, for example, can lead to the discovery of rising damp once a more comprehensive survey is carried out. This is why it’s always essential to deal with any damp problems as soon as possible.
In contrast to Rising Damp, other damp problems like condensation or penetrating damp stem from localised or distinct sources. Condensation is typically caused by moist air, often from activities like showers or boiling water on the stove. Penetrating damp refers to the horizontal infiltration of water through a building’s external envelope, occurring when water enters through cracks, damaged pointing, faulty plumbing, or structural defects. On the other hand, flooding or leaks come from more apparent sources, often due to external factors like heavy rain, overflowing rivers, or plumbing failures. When there is flooding or a leak, the water infiltration is often visible and immediate, making it easier to identify the source than other forms of damp.
The Preservation Company – your local Rising Damp Specialists
The Preservation Company has been dealing with rising damp concerns since its inception. With over 100 years of collective knowledge on damp proofing and property maintenance, you can rest assured that you will be in good hands. We understand what causes Rising Damp and have well-defined treatment processes to deal with rising damp in your home or business. As a qualified damp surveyor, we can diagnose and treat the causes and damage associated with rising damp.
Get in touch with us today to learn more about how we can help protect your property.
