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November 12, 2022

Dealing With Rising Damp Patches On Internal Walls

By Inkar Gazizoff

Sometimes the appearance of damp patches on internal walls in your home can indicate a serious problem with rising damp. This is when water soaks into porous parts of the walls and then needs to evaporate to reach equilibrium with outdoor air.

What causes the problem?

rising damp patches into the walls and floor of your home is caused by a number of different things, including leaks, poor construction, defective drainage systems and condensation.

Poor drainage and internal walls being joined to each other by a shared wall often make it difficult to spot the cause. While you might suspect that damp is occurring as water pools in an odd place, you may not know exactly where the cause lies.


The best way to begin identifying the problem is by a property inspection. If the defects are relatively obvious, you may be able to tackle water intrusion using a few simple measures, such as minor upgrading of defective drains and insulation and replacement of damp or leaky internal walls. However, sometimes it is not immediately obvious where the problems lie.

Talking to your home builder

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If you’re not sure what caused your damp problems and you’ve already had a roof inspection, talk to your builder about any advice he has on this issue.

Taking action before the problem worsens

You still may not know exactly where the problem lies, but are taking action to avoid this from becoming a bigger and more expensive problem for your home.

The first thing you should do is seal any leaks in the outside of your walls with silicone. This will make a huge difference to any problems inside, especially if a burst sewer pipe caused a backup of water inside around the time that it happened. Then, check the following areas of your home:

  • Burst water pipes – These can cause a great deal of damage to both your internal and external walls. It is important to know that water will not naturally travel up a wall. But it will if the pipe burst inside and leaked out through gaps in the mortar joints. If this is the case, then repair work will be required to prevent further damage from higher than usual moisture levels in your home.
  • Sump pumps – Make sure your sump pump is working correctly. It can take a lot of water out of the ground, but if it’s not working correctly, it can back up into the walls and cause damp.

Wall cavity – Check the condition of your wall cavities and make sure that there are no holes or gaps that will allow water to seep in. You should also check for moisture trapped within your wall cavities because this may be damp that cannot escape due to drywall blocking it.