Treating Rising Damp in Old Buildings

Damp is an issue that affects many properties; new and old, commercial and residential alike. There are several types of damp that affect buildings, and whilst it can befall all types of properties, older buildings are more susceptible to certain types of damp, especially rising damp.

This is because when older houses were built, Damp Proof Courses (DPC) were somewhat primitive or entirely absent. Since then, our knowledge of damp has greatly increased and new houses all feature the most effective DPC treatments, but unfortunately, the same can’t be said for older properties which is why so many of them suffer from rising damp.

When it comes to treating damp in old buildings (officially, those built pre-1919), there is an animated discussion about the most advisable course of action. How to treat rising damp in an old house needs to consider both the problem at hand, but also the preservation of the property – especially if it’s a listed building.

When you seek out a rising damp quote for a listed property or otherwise, our team of experts will carry out a full site survey before recommending the best treatment via a no-obligation quote. We have years of experience working on both new homes and period properties across London, meaning our team are best placed to protect your home from the effects of damp without compromising the charm of the property.

Causes of Damp in Old Houses 

As mentioned, old house damp problems can have a range of causes, namely the fact that the DPC in old houses is outdated and not up to modern standards.

Many argue that the way that listed buildings were built is better in terms of keeping a home damp free, however, none of these buildings was erected with modern waterproofing techniques in mind. This means that such properties either use outdated methods to create DPCs, such as slate, bitumen, jute and hessian, or they have none whatsoever. What this means is that the walls of the property have little to no barrier against water in the ground surrounding the property, meaning the moisture can seep in through the walls and cause damage.

In the modern-day, DPCs are usually either plastic membranes or chemical injections into the walls which prohibit damp from rising. These may require replacing over time due to natural wear and tear or as a result of extensions to the home such as an adjoining wall.

How to Identify Rising Damp

Rising damp is relatively simple to identify, even if you are not an expert in the field. The most common sign of rising damp is moss forming on walls on the outside of the building as a result of moisture in the walls.

There may also be damage to plaster on internal walls which may crack or break away as a result of the moisture. When there is rising damp, you will be able to visibly see and feel damp walls in your old house, so if you notice peeling paint, wallpaper or plaster, there’s a high chance you have a case of rising damp.

If rising damp is the issue your old property is suffering from, the damp will extend no further than 1.5m up the wall due to the effects of gravity. If you notice damp higher up the walls or on the ceiling, you may have a separate damp issue.

It is common for new buildings to suffer from a build-up of mould as moisture is not well ventilated. In older properties, the materials used to build walls, such as stone, are described as ‘breathable’. This means that moisture can easily pass through walls, but it does little to protect the property from groundwater causing rising damp.

That’s also not to say that old buildings can’t suffer from a build-up of mould. When it comes to how to prevent damp in old houses, we would recommend:

• Regularly opening windows to allow air to circulate
• Using de-humidifiers in small rooms with limited ventilation
• Keeping furniture away from radiators
• Ensuring extractor fans are installed in the kitchen/bathroom to remove excess moisture and steam in the air

Doing the above will prevent damp problems like condensation. We would also recommend regularly checking things like the windows, doors, rendering/mortar, guttering and roof to ensure there is no damage.

Survey and Rising Damp Quote

Whether you are certain that your home is suffering from rising damp, or if you are seeking an expert opinion, the Garratt’s Damp & Timber team offer surveys and rising damp quotes. With years of experience in the field, our team will inspect the building, diagnose the root cause and advise on the best course of treatment.

Treatments for rising damp include:

• A chemical DPC injection
• Replacement of rotting joists or internal flooring which has come into contact with damp
• Removing and replacing damaged interior plaster
• Bridged DPC – requiring the removal of bridging materials or soil to enable a minimum of 150mm clearance below the DPC

To request a rising damp quote and a survey, please call our team on 0208 535 7536 today, or contact us directly online.