Preventing and Treating Rising Damp: Comprehensive Strategies for Building Owners

Rising damp can affect any property. It doesn’t matter whether you live in a semi-detached house or you own a commercial site, rising damp doesn’t care. It is true that the older the building, the more likely it is to see this kind of problem, but new buildings are not exempt. When it comes to preventing and treating rising damp, what can be done? These strategies for builders will make everything clear.

Why Are Older Properties More Susceptible To Rising Damp?

Older properties, for instance, period ones or pre-war builds, are more likely to see rising damp issues inside their walls. This is because when these buildings were constructed, the knowledge, application, and technology were not yet advanced enough to provide long-lasting solutions, and therefore, decades later, the damage has taken hold.

Spotting Rising Damp on Internal Walls

The first step to figuring out what to do includes understanding what the warning signs and symptoms are. Spotting rising damp on internal walls is both easy and misleading at the same time. This is because it can be misdiagnosed for other types of water damage, therefore the information must be correct before starting treatment. Our team can help with this by providing a home visit and site survey. The major signs to watch out for are explored in more detail here.

Visible Water

If you notice any visible patches of moisture on your wall coming up from the ground and reaching about 1 metre in height, then this is a big sign that the problem is rising damp.

The Smell

It is also very easy to smell rising damp as soon as you walk through the front door of a property. It will be distinctly musty and unpleasant and it is not a smell you want sticking around.

Damage to Décor

Whether it is peeling wallpaper or bubbling plaster, the cosmetic damage of rising damp is unmissable. You might notice that your wall is wet to the touch and your paint is flaking or bubbling. This will impact the plaster underneath, and when this starts happening you can’t ignore the problem any longer.

Mould Spots

Black mould is a common type of household mould that can show up on any property. However, those homes with rising damp problems will experience black mould at some point if the problem goes untreated. This is extremely dangerous for your health and can be difficult to clean and stop.

External Wall Rising Damp Signs

If your external wall is also suffering, which is likely if you have spotted signs inside, here’s what you might notice.

  • The wall is wet to the touch.
  • There are noticeable dark spots where moisture has taken hold.
  • Salt marks

Treating Rising Damp Internally

There are a few methods for homeowners to explore regarding rising damp. This is not a problem that will go away of its own accord, and it can (and will) cause extensive damage to the structural integrity and very foundation of your property if you don’t invest in treatment pathways.

Procuring a Survey

The first step is to call our team and book a site survey. This survey will show exactly how far the damage goes and determine the best path to take to rectify it. Surveys are useful because, without them, there is no real way to tell what needs to happen to fix the walls of the building.

Stripping Back The Wall

When rising damp is noted, then stripping the wall back to the bare frame will be required. This means taking off the wallpaper and the plaster so the damage underneath is visible. This is where any treatment will take place, so it is unavoidable.

DPC Injection Courses

DPC injection courses are the most common route for building owners to take to protect their assets and get back to normality. It is important to have this job done by a fully licensed professional because, without that guarantee, you just don’t know what you’re signing up for. Once qualifications have been verified, a DPC course will take around two days for a smaller area and anything up to a week (or longer) for a bigger space. For example, if you need damp proofing in three big rooms then it could take a few weeks for the job to complete.


How effective are these courses? The answer is, very! As long as a full site survey has been undertaken and the extent of the damp is observed, a comprehensive professional course should do the trick.

Steps to Take Post-Treatment

After the damp proofing course is complete, it is typical to need to wait a set period before you can redecorate. While this may be frustrating, it is necessary to ensure that the proofing is completely viable and that all the moisture has evaporated from the walls. Decorating too soon is a waste of time. Once this waiting period has been observed, you can paint the walls. The proofing course, if done professionally, should stand the test of time.

The Consequences of Ignoring Rising Damp

If you ignore rising damp then there are a few things that are likely to happen. Firstly, you will never be able to decorate properly and therefore the aesthetic of your room will be impacted negatively. For instance, peeling wallpaper and paint that bubbles or doesn’t ever go on properly are two of the biggest ones. Secondly, it will compromise the structural capacity of your property so the problem will continue to worsen over time and it will become a bigger job the longer it is left. Bricks may crumble and parts of your home could need re-strengthening. So it makes sense to get the job done as early as possible, which means as soon as you spot any signs.

Treating rising damp in properties is easy with a DPC. It is impossible to do without expert guidance and input, and our team is here to help. Homes that have rising damp need special attention as soon as possible to avoid further damage, so don’t delay.

Rising Damp in Basements: Waterproofing Techniques for Below-Ground Areas

The basement is an important part of a house but is often overlooked. Doing this is costly because damp issues can cause problems across the home. The main issue with basements is that they are susceptible to moisture buildup and water leaks. Rising damp is a particularly serious concern because it can weaken the home’s structure in addition to doing other damage.

Understanding Rising Damp

Moisture can travel up a wall through capillary action. This happens when the wall is porous enough, with the best example being brick walls. These pores act like a series of many straws, transporting water upwards, which then causes damage.

Since basements are in direct contact with the ground, they are one of the places this issue starts. Basement waterproofing can help address this issue. Because every home and its basement is different, the right solution will depend on the type of foundation, the home’s location, and the issue causing rising damp. This article looks at the most common waterproofing techniques that ensure the basement and the surrounding area remain dry.

Use Epoxy Injections and Sealants

Both techniques are considered short-term solutions that are only used before a homeowner instals a more robust solution. They are best used when the cause of damp is cracks in the basement walls, such as cracks in the masonry that hold everything together.

A contractor will apply the epoxy or sealant into the wall, so it fills the whole crack and flows to the exterior, effectively sealing the crack. Doing this stops water from ingress through the cracks, helping eliminate one of the causes of rising damp.

Although they work well, there are certain things homeowners should know before using them. First, you should not use them on painted walls or where there is efflorescence. Efflorescence is mineral deposits that form on concrete walls. Paint and salt deposits make the epoxy and sealants adhere poorly, which means you will not have great results and will likely be damp again after a short while.

Second, they can crack and become ineffective. Basement walls expand and contract depending on factors like temperature, moisture content, outside water pressure, and the natural movement and settlement of a house as it ages. When any of this happens, the mortar will crack alongside the sealants and epoxy used to prevent water seepage.

Solutions that work well without cracking include porous foams, flexible sealants, and impermeable membranes that also waterproof a basement well without cracking due to expansion and contraction cycles.

Use Tanking to Prevent Rising Damp

Tanking uses a slurry to make a wall impenetrable to water and is a great solution for basements with a rising damp problem. Once it has been applied to the wall and dried, it creates a waterproof coating that stops water ingress.

One critical thing to know about tanking is that it does not solve any underlying causes of damp. For example, it cannot solve the issue of a leaking pipe that makes the basement walls wet or condensation that does the same.

The slurry used in tanking contains Portland cement and other constituents that ensure adherence to the basement walls. Because of how these additives work, proper preparation is crucial to prevent tanking failure in the future.

Once the tanking mixture is ready (it also comes premixed), you or the contractor will apply two to three coats to your walls, waiting for each to dry before applying the next. Once dry, you can paint over it and then decorate the basement as you like.

You can also use tanking before applying plaster if you have been renovating or converting the basement. The underlying tanking layer will provide additional protection to the wall behind it and the plaster in front of it.

Use Cavity Wall Waterproofing Systems

Cavity drain systems are a popular option for new construction, basement conversions, and retrofitting cellars. They are often installed to counteract hydrostatic pressure, which occurs when water pressure exerts forces on the basement’s retaining walls. While the walls will provide some resistance, any weaknesses in them will cause water ingress into the basement, rising damp, and other issues.

Cavity drain systems use cavity membranes and a drainage system to channel water safely out of a property, protecting the basement and any possessions in it. The contractor instals the cavity membranes to the floor and walls, ensuring all surfaces are covered.

Once installed, the membranes leave a small gap between themselves and the underlying surface due to their studs. This gap allows excess water to flow down the cavity between the membrane and the underlying surface, relieving water pressure.

All water that enters the basement and travels behind the membrane is channelled into a drainage system. It is then directed to a sump pump chamber that the contractor installed below the floor slab, which pumps the water out of the property and into an external drainage system.

Some designs also allow the water to be diverted to the external drainage system without using a sump pump. These options allow you to keep your basement dry whether you have power or not because they do not rely on it. However, systems using a sump pump can have optional battery backups.

Installing these systems is never a DIY task, so you should hire a contractor to ensure it is done right. Doing it yourself means you might not be able to meet the required specifications, and you might cause weak patches that will cause damp and flooding issues in the future. The risk of damage to your property, the cost of the subsequent repair, and the cost of installing the waterproofing solution again are not worth doing this yourself.

Ensuring your basement is waterproof can help prevent many issues, including rising damp. The solutions you pick will depend on your preferences, budget, and how serious the issue is. It is also best to let a specialist company like us waterproof your basement because doing so can involve extensive work and a significant risk of damaging the home.

Understanding the Differences Between Rising Damp and Other Forms of Dampness

With the ever-changing nature of the British weather, dampness within buildings is a very common challenge that can lead to a range of problems, from structural deterioration to compromised indoor air quality. Among the various types of dampness, rising damp is often misconstrued as the sole culprit. However, it’s important to differentiate between rising damp and other forms of dampness, as each form has its own distinct causes, characteristics, and solutions. That’s why in this guide, we’ll be delving into the world of dampness, to better understand the differences between rising damp and its counterparts.

What is Dampness?

Before investigating the specifics of rising damp, it’s essential to grasp the broader context of dampness. Put simply, dampness is the presence of unwanted moisture within the structure of a building, and it can manifest in different forms, each stemming from various sources. The three most common categories of dampness are rising damp, penetrating damp, and condensation, so first, we’ll explore each of these forms in detail.

What Causes Rising Damp?

Rising damp occurs when moisture from the ground is absorbed by capillary action through porous building materials such as bricks and mortar. Defined as the ability to flow through narrow spaces, often in opposition to gravity, capillary action enables water to climb interior and exterior structural walls.

What are the Characteristics of Rising Damp?

Signs of rising damp include damp patches or staining on lower sections of walls, a musty smell, and plaster that may start to degrade. As the water rises, it often brings salts from the ground, leading to white deposits on the walls known as efflorescence.

How Should I Treat Rising Damp?

Treating rising damp can be tricky, as it typically involves installing a damp-proof course (DPC) or using modern chemical injection methods to create a barrier that prevents moisture from ascending. Repairing affected plaster and masonry might also be necessary, to prevent the problem from returning.

What Causes Penetrating Damp?

Penetrating damp differs from rising damp, as it occurs when water infiltrates a building from external sources like rain, leaks, or faulty plumbing. It can affect walls, ceilings, and floors, and it usually spreads horizontally rather than vertically. 

What are the Characteristics of Penetrating Damp?

Penetrating damp often presents as damp patches that extend horizontally from the point of entry. The affected areas can become discoloured, and there might be visible watermarks. Unlike rising damp, it’s not limited to the lower sections of walls, so you might find that penetrating damp spreads faster than rising damp, despite it being a little easier to treat.

How Should I Treat Penetrating Damp?

The key to dealing with penetrating damp lies in identifying and rectifying the source of water entry. This might involve repairing leaks, improving external wall surfaces, or even fixing damaged roof components. While this might be a large repair, once it’s finished, penetrating damp is unlikely to return.

What Causes Condensation?

Condensation occurs when warm, moist air comes into contact with cold surfaces, causing the air to release moisture in the form of water droplets. It’s more prevalent in poorly ventilated spaces, so older buildings are often victims of condensation.

What are the Characteristics of Condensation?

One of the first signs of condensation is the appearance of water droplets or damp patches on windowsills or in the corners of a room. After this, mould growth is a common consequence, which can lead to a musty odour or even potential health concerns. Because of this, it’s important to spot and treat condensation as early as possible.

How Should I Treat Condensation?

To tackle condensation, improving ventilation and reducing moisture sources is key. This might involve using extractor fans or dehumidifiers, ensuring proper insulation, and heating the property correctly.

What Features Make Rising Damp Different to Other Forms of Dampness?

It can sometimes be difficult to identify the type of dampness in your property, especially if the characteristics of the problem are common features of all damp types, such as water patches. You might be worried that the problem is rising damp, which can have a significant impact on the structural integrity of your property. However, rising damp usually stands out from other forms of dampness due to its specific set of characteristics and underlying causes. 

  • Capillary Action as the Driving Force: The primary characteristic of Rising damp is its reliance on capillary action to draw moisture upward through porous materials. This fascinating phenomenon occurs when the surface tension of water allows it to move against gravity in confined spaces. Unlike penetrating damp and condensation, which are influenced by external factors like rainfall and differences in temperature, rising damp is rooted in the building’s relationship with the ground.
  • Localised and Low-Lying Damp: Rising damp typically affects the lower sections of walls and is most pronounced at ground level. This localised nature sets it apart from penetrating damp, which usually manifests higher up the walls and across larger surface areas.
  • Salt Deposits: One of the telltale signs of rising damp is the presence of white, powdery deposits known as efflorescence. These deposits form as moisture rises through the wall, carrying salts from the ground. As the moisture evaporates, the salts crystallise on the surface, leaving visible residue.

How Can I Diagnose and Address Dampness?

Distinguishing between rising damp and other forms of dampness is crucial if you want to tackle your damp problem with the right solution. What’s more, a misdiagnosis can cause ineffective treatments that not only waste time, but that ultimately fail to alleviate the underlying issue. To correctly diagnose and address dampness, we recommend a simple three-step process:


A thorough inspection by a qualified professional is the first step. They will assess the location of any dampness, visible signs, and potential sources of water infiltration. This evaluation will guide the identification of the specific dampness type.

Identifying the Source

Accurate diagnosis hinges on identifying the source of dampness. For rising damp, this might involve checking for the absence or failure of a damp-proof course, while penetrating damp may require investigating leaks or poor external wall conditions.

Tailoring Solutions

Each form of dampness demands a tailored approach. Rising damp might require the installation of a DPC, while penetrating damp needs source repair and condensation could demand improved ventilation and moisture control. The variety of solutions out there means that the better you tailor the solution to the problem, the quicker the treatment will work.

Dampness is an issue that encompasses various forms, each with its unique characteristics. While rising damp garners significant attention, it’s important to recognise the distinctions between the forms of damp, as accurate identification is the foundation for effective treatment. By understanding the unique features of each type of dampness, property owners and professionals can work together to create healthier and more comfortable living and working environments.

The Importance of Building Maintenance in Avoiding Penetrating Damp Issues

When you think of the safety and longevity of a building, regular maintenance often plays a crucial role. One of the primary concerns for UK property owners and managers is the issue of penetrating damp. By investing in regular building upkeep, you can fend off such problems and ensure your premises remain robust and welcoming.

Understanding Penetrating Damp

At its core, penetrating damp is an external moisture issue. Unlike its counterpart, rising damp, which originates from the ground below, penetrating damp is the result of water ingress from the exterior of the building. This means that it can affect walls, ceilings, and even roofs. The damp is not restricted to the base of walls; it can appear at any height depending on the source of the problem.

Causes of Penetrating Damp

Several factors can lead to penetrating damp:

  • Weather: In Britain, our buildings are often exposed to relentless rain, strong winds, and occasional snow. Persistent bad weather can lead to water seeping through any vulnerabilities in a building’s outer shell.
  • Structural issues: Flaws like cracked rendering, damaged brickwork, faulty roof tiles, or compromised window and door sales can allow water to penetrate.
  • Poorly maintained gutters and downpipes: Blocked gutters can cause water to overflow and saturate walls. Similarly, damaged downpipes might not channel water away effectively.

Impact on Buildings

Having penetrating damp can be harmful to structures. Continuous water ingress can weaken the integrity of materials, leading to more extensive damage over time. What’s more, damp walls act as a conduit for cold from the outside, which can increase your heating costs during colder months.

Spot the Signs Early

Recognising the early symptoms and signs of penetrating damp is crucial – not just to save money on repairs but also to protect the structural integrity of your property. Some of the main things to look out for include:

  • Persistent wet patches: Unlike a spill or an isolated case of condensation, these damp patches on walls, ceilings, or floors don’t seem to dry out, irrespective of the weather or heating conditions. The location of these patches can often give clues about the source of the problem. For example, a damp patch on the upper wall or ceiling might hint at issues with the roof or upper brickwork.
  • Plaster and paintwork damage: Water ingress can cause paint to bubble or peel. Plaster may also start to flake or crumble to the touch when subjected to prolonged moisture. This degradation isn’t just unsightly; it’s an open invitation for serious structural issues if left unaddressed.
  • Distinctive musty smell: Penetrating damp often brings a distinctive odour, reminiscent of wet clothes left in a closed space for too long. It’s a damp, musty scent that lingers, especially in poorly ventilated areas.
  • Mould or mildew appearance: Mould and mildew thrive in damp environments. The early stages might show up as small, dark spots, but over time these can grow or spread.
  • Watermarks or tidemarks: Sometimes, you might notice faint lines or watermarks, particularly on walls. They can be indicative of where water has travelled or pooled, making them valuable clues in diagnosing the damp’s source.
  • External wear: It’s not just the inside of the property you should be concerned about. External signs like deteriorating mortar between bricks, damaged or misaligned gutters, and noticeable wet patches after rain can all be early indicators of potential water ingress points.

The Benefits of Regular Building Maintenance

  • Cost saving: Over time, the financial toll of repairing damage caused by penetrating damp can be hefty. Regular maintenance checks and repairs can prevent minor issues from becoming major, leading to more expensive issues.
  • Preservation of property value: A well-maintained building not only looks appealing but also holds its market value. On the other hand, a property plagued with damp issues can see its value plummet, making it a less attractive investment.
  • Health benefits: Damp and mould can be detrimental to our health. By ensuring your building is free from penetrating damp, you safeguard the health of its occupants, providing a comfortable and safe living or working environment.

Key Types of Building Maintenance to Prevent Penetrating Damp

Building maintenance isn’t one-size-fits-all; the best approach is tailored to the unique needs of each building. To protect your property from issues like penetrating damp, it’s essential to understand and implement various types of maintenance.

  • Gutter cleaning and maintenance: Regularly remove leaves, twigs, and other debris from the gutters. Check for any sagging or misaligned gutters and correct them as needed. Plus, inspect the downpipes to ensure they are not blocked and are directing water away from the building.
  • Roof inspection and repair: Regularly inspect your roof, including the tiles, slates, and flashings for any damage. Any broken or missing tiles should be replaced as soon as possible. You should also regularly check and maintain seals around chimneys and vents.
  • External wall inspection: Look for any cracks or gaps in the brickwork or rendering and apply weather-proof or filling solutions where needed. Ensure that any cladding or external finishes remain intact and water-resistant.
  • Window and door maintenance: Regularly check your windows and doors to ensure seals remain intact. Any cracked or damaged glazing should be replaced as soon as possible. Plus, check for draughts and address them – they might be an indication of potential damp ingress points.
  • External painting and sealing: If painting the exterior, always use quality, weather-resistant paint. Plus, regularly check and refresh any waterproof coatings or sealants on your building’s exterior.
  • Ventilation systems: Ensure that any vents function correctly, especially in damp-prone areas like kitchens and bathrooms. If your property has extractor fans, clean and maintain them regularly.
  • Landscaping: Trim any trees or shrubs near the building to ensure that they don’t hold moisture against walls and roofs. If you have any water features in the garden, ensure they don’t cause splashback onto the building.

Even with a careful maintenance plan, penetrating damp can be a common problem in UK homes. If you have noticed signs of penetrating damp, or want a survey carried out on a property to check, get in touch with London Damp Specialists.