Condensation and Damp Walls

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Our Surveyors pride themselves on a high standard of work. We can offer a range of services including Building Surveys and Home Buyers Reports, together with independent Valuations (please note these are not for bank lending but are to advise you how much we feel the property is really worth). We also carry out Dilapidations Reports and Schedules of Condition and Property Reports, plus Specific Defects Reports (also known as Engineers Reports or Damp Reports).

If you have a property problem we may even already have written an article on it and we would refer you to the many articles we have on our Free property articles page.

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Why are my walls damp?

Damp walls occur for many reasons. They can be very inconvenient, not only damaging the wall paper or the paint finish, also mould can occur on clothing and can also be bad for your health. We have seen dampness at high level, it can be leaking roofs, gutters or hopper heads. These tend to occur around the top of the wall and the ceiling.

At mid-level to the property it could be the central wall, this is often caused by leaking downpipes or defective pointing, or poorly fitted windows or a missing damp proof course to the windows.

At ground level rising damp tends to get blamed for all problems, but as you will see from reading this article and contacting us on our free phone number, 0800 298 5424, dampness at ground level can be for many reasons, everything from drains and gutters and gullies blocking, to downpipes discharging against the wall, or a high water table level. Whatever the reason, it can cause a situation that is very unpleasant to live in.


Gutters can be to blame for dampness on walls

Dampness put simply

To establish exactly why a wall is damp you do need to consider many possibilities. Some of these you can effect by altering how you use the property and some of them you cannot. So, it makes sense to look at the damp problems that you can resolve.

Dampness that you can help to solve

Probably the most common cause of dampness is condensation and this can be resolved or reduced considerably by changing the way that you use the property.



Identifying condensation

Tell tale signs of condensation are mould on the walls and furniture and on clothes and literally windows that are dripping wet. Condensation is where the moisture content of the air meets a cold surface, such as a window, and then the dampness occurs. This is very easy to see if it is on a window where it causes a misting effect, but it can be virtually undetectable at first if it is onto a papered wall and often the first signs are when the mould occurs. It tends to occur more within the corners of the property in areas that are colder.


Black mould on a wall


Black mould caused by condensation

So what can I do about condensation?

To reduce condensation you need to increase the flow of air in the property. This can be as simple as opening the windows or using the trickle vents that are on the windows (small vents that open, often set at the top of windows) or using any vents that are set in the walls.

Condensation has become more common as we have made our houses more airtight. This was never a problem in years gone by, when we had rattley old sliding sash windows and wooden casement windows that didn't fit properly and also there was less things causing condensation. Today we have many items such as showers, washing machines, kettles, steam cooking, etc, to add to the moisture content of the air.


Air movement


Air bricks provide natural ventilation


Air brick allows airflow in room

It really can be as simple as opening the windows to bring in some fresh air that has less moisture content. We do appreciate that this is easier said than done during the winter months when it is freezing cold outside and the last thing you want to do, having warmed up a room, is to allow cold air into it. In such a case as this, if you haven't got trickle vents on the windows or a vent into the house, then you need to add them. If the problem is in an area such as the kitchen or the bathroom then you need to add extractor fans. Remember the key to using condensation is to have air that doesn't have much moisture in it.


Trickle vents

Extractor fans and condensation

An example of condensation that we are coming across more and more is where an extractor fan is installed in the bathroom to take away the excess moisture but unfortunately does not vent to outside air. We often find where ceiling extractor fans are fitted (these are very popular where a light is fitted or if they are fitted directly over the shower) the extract flue is left to discharge into the roof space or attic, rather than taking it to a vent to outside air.

In the photographs below the venting pipe from a shower has been damaged and is allowing humidity to transfer into the area.


Damaged venting pipe from a shower


Damaged venting pipe

The reason this is the case is because it is much harder to get it vented to outside air. We have been into a roof where literally it was like a rain forest. You could tap the underside of the felt in the roof and get covered with water. Fortunately, we only see this once every five to ten years but we can only imagine it is going to become more common with the general increase in thermal efficiency of houses. Whilst we feel thought has been has been given to the air change in properties there is a big human factor in having to use the extract fans in the bathroom and kitchen and having to maintain them once they are broken.

You may be interested in these other articles about dampness and condensation:

Dampness in Buildings - Basics Article
Shared Freehold and Problems with Dampness
Condensation Problems
Damp Walls
Damp Meters
Rising damp, condensation and damp through your walls

Please see our section on:

Specific Defects Reports

What do the ovals or circles in our building surveys mean?

We utilise a system of ovals and circles within our structural surveys and building surveys to highlight problem areas so that you are not left wondering what the problem is.


Condensation on a window. This can
be caused by drying washing on a

Independent Expert Opinion

If you truly do want an independent expert opinion from a surveyor with regard to structural surveys, building surveys, structural reports, engineers reports, specific defects report, dampness issues, dilapidations, home buyers reports or any other property matters please contact 0800 298 5424 for a surveyor to give you a call back.

Caveat Emptor - why have an independent building survey?

You should always have an independent building survey carried out if you are thinking of buying a property as this will highlight any problems. Caveat emptor means buyer beware and means you would be liable for any problems; the estate agent is working for the seller of the property and may not advise you of any problems.

Our Good, Bad & Ugly surveys!

Over the past decade or more we have listened to feedback from our clients and have devised our Good, Bad and Ugly survey which is a building survey, also sometimes known as a structural survey. This survey has been written in easy to understand and read plain English and describes all issues found in the property clearly and in a lot of detail.

We can email you examples of our structural surveys and specific defect reports

If you are interested in having a structural survey or even a Specific Defect Report on any property problem caused dampness please call us and we would be happy to email you some examples of our tailor made reports.

Our Surveying articles

We hope you found the article of use and if you have any experiences that you feel should be added to this article that would benefit others, or you feel that some of the information that we have put is wrong then please do not hesitate to contact us (we are only human).

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