Rising Damp is one of the most commonly found problems in homes throughout London, especially in the older housing found all around the city. Victorian and Edwardian homes in particular were built without many of the modern damp protection systems we expect to see in modern homes, and in many cases where damp proof courses have been installed in older properties they have since failed or deteriorated over time.
Recognising the signs of rising damp early can be incredibly useful, helping property owners reduce the overall damage that damp can do to internal finishes, structural timbers, masonry, and even decorative plasterwork if damp is left untreated.
So, to help homeowners recognise rising damp early, below you can find 7 of the most common signs your London property might have rising damp.
1: Tide Marks on Internal Walls
This is one of the most common and telltale signs of rising damp, tide marks look like a horizontal water stain up to about a meter above ground level on your internal walls. They can appear like a faint watermark or tide line, like the wall has recently been rained on in comparison to the rest of the wall.
These stains are down to moisture rising up through the masonry from the ground in a process known as capillary action.
2: Salt Deposits on Internal and External Walls
White, powdery deposits on your walls (known as efflorescence) are a very common sign of rising damp. These deposits can form on masonry or plasterboard when moisture evaporates and leaves behind mineral salts in the wall.
These salts are collected in the moisture drawn up in the capillary action process, from within the ground and the building materials themselves.
These marks from efflorescence are often associated with rising damp, and over time (if left untreated) they can cause plaster to deteriorate and decorative finishes to fail.
3: Peeling, Blistering Paint, and Ruined Decoration
The moisture drawn up into walls from rising damp can easily cause paint and wallpaper to lose adhesion and start peeling away from your walls, or flaking off.
This might be most noticeable along the lower sections of walls, where the wall is closest to the ground, as the level of moisture present might be higher here than further up in the wall. If not treated, this can get worse over time, ruining more of your finishes as the damp spreads.
4: Damp, or Crumbling Skirting Boards
Rising damp can have strong and damaging effects on a skirting board, as timber can be particularly vulnerable to the effects of prolonged exposure to moisture.
The timber making up the skirting board might start to feel soft, look like its in a state of decay, and could even start curving away from the wall itself. If left untreated long enough its possible for the skirting board to develop dry rot, and this means that the skirting would need either repairing or replacing entirely.
5: Damp Patches Appearing Close to the Floor
Damp patches appearing close to the floor of your home can be a sure fire sign of rising damp in the property.
Properties in London that do have a rising damp problem will often have visible damp patches close to ground level that might feel cold and slightly damp to the touch.
You could easily get this confused with condensation, but a key sign that it’s rising damp is that the moisture appears within the wall itself, whilst with condensation the moisture beads on the surface instead.
6: Musty Odours Only in Ground Floor Rooms
Everyone knows that damp is often associated with musty smells that wont go away even after cleaning. These smells are often brought about when untreated damp has allowed for the growth of mould or dry rot, and can be particularly noticeable in ground floor rooms and basements.
If you have noticed that ground floor rooms in your property have developed a musty smell, but upstairs remains largely unaffected then it could well be a rising damp issue, as rising damp does not travel higher than around one meter above ground level.
7: Damage to Plaster on Internal Walls
Rising damp travelling through masonry can easily cause plaster to break down over time. Common signs of damp damaging plaster can include the plaster bubbling, cracked plaster surfaces, and plaster becoming loose and powdery.
If the damp isn’t treated it can quickly and easily lead to the plaster needing to be removed and replaced, but this shouldn’t be done until the underlying problem allowing for the moisture is dealt with.
Why is Rising Damp a Common Problem in London Properties?
Plenty of homes across London were built before the introduction of modern damp proofing, and especially before damp proofing was included as a standard part of newly constructed properties.
With this being the case plenty of homeowners discover rising damp taking hold after particularly heavy bouts of rain, or after an installed damp proof course has failed.
Some of the most common factors that can contribute to rising damp include
- Ageing or damaged damp proof courses
- Raised external ground levels
- Blocked air bricks or ventilation options
- Bridging of damp proof courses by external materials.
Older properties with aged bricks are particularly vulnerable when it comes to rising damp and moisture movement within.
When to Seek a Professional Damp Survey?
Whilst all of the signs listed above are key signs that a property might have a rising damp problem, they might indicate a larger problem not just limited to rising damp.
A professional damp survey will be able to determine the source of the moisture effecting your walls, and identify the most appropriate and effective remedial treatment from our Property Care Association (PCA) qualified specialists.
We assess walls, floors, and sub-floor areas for signs of rising damp, penetrating damp, and condensation. Moisture readings are taken, ventilation is reviewed, and we check whether the damp proof course is present, bridged, or failing.
Following the survey, you will receive a clear written report explaining the cause of the issue, along with practical recommendations and a no-obligation quotation for the required work.
Damp Surveys and Property Purchases in London
Rising damp, and other forms of damp, are sometimes identified in the property surveys that are needed on behalf of mortgage lenders during the property buying process. In these instances its often recommended for the purchaser to arrange for a specialist damp and timber survey, from a surveyor qualified with the PCA so the extent of the damp can be fully established.
Timberwise can carry out these pre purchase damp and timber surveys to help both the buyer and the lender fully understand the extent of the damp, and whether repairs could be in order before any choice to commit to the purchase has been made.
Do You Need Advice About Rising Damp in London?
If you are concerned that a property you own might be displaying signs of rising damp then a professional inspection from our London based team of PCA qualified experts can help.
We provide specialist damp and timber surveys across London, and we can also carry out any remedial damp proofing, timber repair, or timber replacement works to make sure any property remains damp free long into the future.
FAQs
Can Rising Damp Affect Modern Homes?
Although rising damp is more commonly associated with older properties, modern homes can still experience rising damp if the damp proof course becomes damaged, bridged or poorly installed. External ground levels, construction defects or alterations to the building can allow moisture to bypass the damp proof course and travel up the wall structure.
How High Can Rising Damp Travel Up a Wall?
Rising damp typically affects the lower portion of walls and is most commonly found up to around one metre above floor level.
Does a Damp Proof Course Stop Rising Damp?
A damp proof course (DPC) is designed to prevent moisture from rising through the walls of a building. When functioning correctly, it forms a barrier that blocks groundwater from travelling upward through masonry. However, older damp proof courses can deteriorate over time or become bridged by raised ground levels or external materials, allowing moisture to bypass the barrier.
Is Rising Damp Common in London Properties?
Rising damp is often reported in older London properties, particularly those built during the Victorian and Edwardian periods. Many of these buildings were constructed before modern damp proofing standards were introduced, and damp proof courses may have deteriorated with age. External ground levels, historic alterations and dense urban construction can also contribute to moisture problems.
Do Property Surveys Identify Rising Damp?
General property surveys may highlight visible signs of damp and recommend further investigation. However, surveyors often advise a specialist damp and timber inspection where moisture problems are suspected. A dedicated damp survey can assess moisture levels within walls, examine the condition of the damp proof course and identify any associated timber risks.
