Peeling plaster due to damp on a wall

Types of Damp

Key Takeaways

Definition of Damp: Damp is the presence of excess moisture in a material, space, or environment, occurring in both residential and commercial properties.

Various Types of Damp:

  • Condensation: Caused by warm air meeting cold surfaces, leading to visible water droplets, especially in high humidity areas. Proper ventilation is crucial for prevention.
  • Rising Damp: Water penetrates from the ground, common in pre-1875 homes lacking damp-proof measures. Signs include wall discoloration, paint issues, and musty smells. Professional advice is recommended for treatment.
  • Penetrating Damp: Water enters from external sources like roofs, walls, or plumbing issues. Causes include roof problems, gutter issues, and poor-fitting doors/windows. Prevention involves regular maintenance and thorough correction of leaks.

Issues Arising from Damp: All types of damp can lead to damaging issues such as mold, wet rot, dry rot, timber damage, and more. Rising damp requires varied strategies, including damp-proof membrane installation, damp-proof course repair, or improved ventilation. Penetrating damp can cause severe problems and requires identifying and correcting the source of leaks.

What’s damp? For those who don’t know what it is, in simpler terms, it is the presence of excess moisture in a material, space, or environment. Damp usually happens in residential properties, but that doesn’t mean commercial properties are safe from it. It can be everywhere, given the right environmental factors are aligned for its rise.

What matters is the way damp manifests itself, and that’s where the part – “types of damp” comes into light. Damp is of various types – penetrating damp, rising damp, condensation, leaks, groundwater damp, etc.

All these different types of damp further give rise to various other damaging issues such as mould, wet rot, dry rot, timber damp, brickwork damage, plasterwork bubbling, etc. So, whatever the type of damp, all of them need professional treatment so that you can get rid of it.

But before starting the treatment, you should know what type it is and what is causing it. And that’s what we will be talking about today. So, let’s get in.

Peeling plaster work due to damp


Condensation dampness occurs when the ambient air within a place is warmer than the surrounding environment, causing atmospheric moisture on cold surfaces to condense into observable water droplets on surfaces such as windows and walls.

Spaces with high humidity levels, such as bathrooms, kitchens, laundry drying facilities, and bedrooms, are especially vulnerable to the formation of this condition.

Condensation dampness can cause the creation of hidden mould forms, particularly around window openings, in addition to the visible appearance of water droplets. If left untreated, this mould can harm plaster, paintwork, floor coverings and window frames.

More importantly, the growing mould is a hazard to respiratory health and needs immediate action.

Avoiding the onset of condensation damp is critical for good and healthy living environment and circumstances. The most effective preventative approach is to provide enough ventilation throughout one’s residence.

How to Approach Ventilation to Get Rid of Condensation?

Nowadays, sophisticated ‘flow vents’ strategically positioned at the top area of windows provide a nuanced and regulated mechanism for background ventilation accessible via a switch interface.

Furthermore, modern window designs frequently have the enhanced feature to ‘lock the window open.’ This revolutionary feature allows for the entrance of fresh air while keeping a secure atmosphere, giving the ventilation system an added layer of adaptability.

Installing extractor fans in essential areas such as bathrooms and kitchens is critical for proper ventilation performance. It is recommended that these fans be turned on for at least five minutes after cooking or swimming.

When a bathroom lacks an exterior window but has a shower and/or bath, installing an extractor fan is highly beneficial. This unique fan runs through moist air at a low speed and volume on a constant basis, successfully minimizing moisture-related difficulties.

Rising damp on a wall

Rising Damp

Rising damp, a common damp issue in buildings, is probably recognizable to you, but you may not be aware of its complexities. This sort of damp happens when water penetrates into a structure from the ground, usually harming the floor also.

It is more frequent in homes, particularly those built before 1875. Before this time, laws were not put in place requiring the installation of a damp-proof membrane or damp-proof course in every UK home, with the goal of treating rising damp, waterproofing homes and preventing water ingress.

If damp is detected in a residence built after 1875, it is frequently the result of a flaw in either the damp-proof course the membrane, or both.

Wall discolouration, peeling paint or blistering paint, tidal marks on walls, damage to skirting boards, and an awful, musty smell are the chief signs of this form of dampness.

Given the seriousness of this damp problem, it is strongly advised to seek the advice of a RICS-licensed chartered building surveyor. Their advice may assist you in determining the core cause of the damp problem and directing you toward a suitable remedy.

How to Prevent Rising Damp?

It is highly recommended to thoroughly investigate the presence of membrane installation and a damp-proof course before wrapping up a property purchase.

For homes that have a chemically injected damp-proof membrane, it is critical to undertake a thorough survey of its efficacy while also ensuring the inclusion of an insurance-backed warranty.

The investigation is required to guarantee that the elevation of garden soil immediately next to the residence does not exceed the level defined by the damp-proof barriers.

Furthermore, it is the responsibility of the potential homeowner to guarantee accurate design and continuing maintenance of all gutter systems, so avoiding the possibility of ground saturation.

How to Treat Rising Damp?

Addressing the issue of rising damp requires a varied strategy that may include the installation of new damp-proof membranes or barriers, repairing of the existing damp-proof courses, or the improvement of ventilation in the house.

In the case of older homes that lack adequate ventilation or damp-proof courses or have weaker ones, it’s critical to recognize that modern renovations, such as insulation or plastering, may unintentionally make worse damp-related issues by reducing natural airflow within the structure.

Therefore, it is strongly encouraged to get expert advice before starting any restoration projects since ill-informed investments of time and resources may result in worse situations.

Penetrating damp and moisture on ceiling

Penetrating Damp

This kind of damp is often the most severe, causing increased problems. Penetrating damp occurs when water infiltrates the external walls of a structure via its roof, walls, or other house structures. Its causes are not limited to external factors; it can also be caused by problems inside the inner plumbing system.

What are the Common Causes of Penetrating Damp?

  • Roof issues such as loose or broken tiles, damaged flashing
  • Gutter problems such as overflowing or damaged gutters and downpipes due to leaves or damage
  • Exterior wall damage, such as cracks or issues with pointing, cladding, render, or pebbledash
  • Poorly fitting doors and windows that might need repair
  • Leaks in interior pipes

What Signs Indicate Penetrating Damp?

Signs of moisture issues indoors can include:

  • Brown stains resembling damp patches on walls, ceilings, or near chimneys
  • Plaster that is wet and crumbling
  • Formation of large bubbles under plaster, which may result in ceiling damage if not addressed promptly

How to Prevent Penetrating Damp?

To successfully minimize the penetrating damp, it is critical to maintain the structural integrity of solid walls within the building, addressing any possible difficulties with efficacy. A complete strategy is suggested that includes the following steps:

  • Examine your roof area on a regular and methodical basis, looking for signs of water intrusion or any symptoms of timber moisture.
  • Assure that air bricks or other similar ventilation and moisture-preventing devices are free of obstructions to allow for unrestricted airflow.
  • Maintain your external pointing and painting with care, executing prompt and competent repairs to protect against any breaches that might lead to penetrating damp.

How to Treat Penetrating Damp?

The recommended method for treating penetrating damp involves an approach that requires first identifying the leaking source, followed by a thorough correction of the problem at its source.

It is strongly advised to hire a competent damp surveyor, such as Damp Surveyors Ltd., which is a member of the Royal Institution of Chartered Surveyors (RICS). Damp Surveyors Ltd is a qualified expert who does a thorough damp survey and provides detailed advice on the most efficient remediation techniques.

You should also talk to your neighbours to see whether they are dealing with similar problems. This joint effort has the potential to speed up the process of determining the fundamental cause of the issue, allowing for a quicker resolution.

Moisture damp on a wall

Arrange Your Damp Survey Today!

Handling untreated damp in a property can be a costly and troublesome issue, particularly for landlords. It’s essential to address the problem early on to prevent it from becoming more challenging.

If you want to learn more about various types of damp or need a quote for damp proofing, contact our team at 0330 053 3432 today.

What are the 3 types of damp?

Buildings can have three main types of dampness: rising damp, penetrating damp, and condensation. Rising damp is when groundwater moves up into walls. Penetrating damp happens when water comes in from outside, like leaks or flaws in the roof or walls. Condensation, the most common type, occurs when warm, moist air meets a cold surface and forms water droplets. It’s important to identify the type of damp for successful fixing.

What is the most common form of damp?

Condensation is a common type of dampness in buildings, happening when warm, moist air meets cold surfaces, resulting in water droplets. This occurs in poorly ventilated or inadequately heated areas, or where there’s excess indoor moisture. Condensation typically shows up on windows, walls, and ceilings, leading to problems like mold. To address condensation-related dampness, it’s crucial to improve ventilation, insulation, and heating in the affected areas.

How do you identify damp?

Finding damp involves visually inspecting and, in some cases, using specific tools. Signs include discolored patches on walls, peeling paint, a musty smell, and mold growth. Rising damp shows as a tide mark, while penetrating damp leaves visible water stains. Condensation is seen as water droplets on windows. Professionals may use tools like moisture meters and thermal imaging to understand the extent and cause of dampness for effective remediation.

Table of Contents

Picture of Sam Fitzgerald – CSRT Damp Surveyor

Sam Fitzgerald – CSRT Damp Surveyor

Author – CSRT Damp Surveyor
Sam is a highly qualified and seasoned damp surveyor with over ten years of specialised experience. With a strong academic foundation in building surveying and numerous professional certifications, Sam has established himself as an authority in the field of damp diagnosis and remediation.

At Damp Surveyors Ltd, Sam applies his extensive knowledge to help homeowners across the UK address and solve their damp issues effectively. His approach combines cutting-edge techniques with a commitment to honest, client-focused service, ensuring that every survey and recommendation is tailored to the specific needs of the property.

As a thought leader, Sam’s insights into damp prevention and treatment have been featured in industry publications, underscoring his role as a trusted expert dedicated to maintaining the integrity and comfort of your home.

Testing device for measuring dampness in a house


At Damp Surveyors Ltd, we stand out as your premier choice for damp survey services in the UK. Our commitment to excellence and customer satisfaction sets us apart. Here’s why you should choose us:

  • Exclusive 3 Free Quotes: We offer a one-of-a-kind optional service where you not only get our top-notch damp survey but also receive 3 free quotes from vetted local companies, giving you peace of mind by saving you thousands on getting the most competitive quotes, and also time researching and contacting other reputable companies.
  • Knowledge and Experience: We provide unmatched knowledge to every survey we conduct thanks to our team of seasoned professionals and years of industry experience. This guarantees accurate assessments and practical solutions.
  • Nationwide Coverage: Whether you’re in a bustling city or a rural area, our services extend across the UK, making us accessible wherever your property is located. Choose us for nationwide reliability and excellence.

Choose Damp Surveyors Ltd as your reliable partner for all-inclusive survey needs. Our top concerns are the health and safety of your property, and we are committed to providing outcomes you can trust.

A damp meter that measures damp

How to Measure Damp in Walls?

Key Takeaways Importance of Measuring Damp in Walls: Measurement of damp in walls is crucial to understanding the extent of the problem and estimating the time required to fix it. It

Read More »
Damp in a bedroom

How To Treat Damp In A Bedroom?

How To Treat Damp In A Bedroom?   Key Takeaways Detecting Damp Signs: Look for signs such as black mould, foggy windows, moist spots, peeling wallpaper, and musty odours. Swift

Read More »

Our Services

Related Posts