Rising damp is a very common problem for residential and business property owners here in London, all it takes is a glance at the wet weather and it’s easy to understand why! If you are seeing the tell-tale signs of rising damp on your ground floor like wet spots, tidemarks, and black mould then it’s likely because your building’s protective measures have been compromised, or are lacking in the first place! The water is being drawn up through your walls by capillary action just like a sponge, and there is nothing in place to stop it.
The mainline of defence against rising damp is called a ‘damp proof course‘, a protective layer that runs between the external ground and your property’s walls. Damp proof course is an umbrella term for various types of applications that suit different situations, your property will generally only need to have one of them in place.
Basically speaking, a damp proof course is there to protect your building’s walls from the moisture that rises up from the ground through the tiny crevices and pores found in many building materials. The most common damp proof course is a barrier laid horizontally where the wall meets the ground to prevent moisture from penetrating the wall and rising up through it. The damp proof course also stops the salts and minerals found in soil that rising damp brings along, which evaporate to cause damage like the discolouration of tidemarks.
The type of damp proof course used for most situations is a physical one, usually a thin, fine sheet of waterproof material that is visible at the walls’ bottom. These are mostly made of slate, plastic, or lead-lined bitumen. This waterproof barrier is put in place to prevent your walls from absorbing the groundwater that is the source of rising damp.
Sometimes the best damp proof course for the job isn’t actually a physical barrier but a chemical one. A chemical damp proof course is injected directly into building materials like brick and mortar near ground level, creating a waterproof layer to stop the rising damp. Chemical damp proof courses are often the best choice if the physical damp proof membrane has been compromised or was never installed in the first place. Installing a physical solution is problematic in an existing structure, making the chemical course the best choice.
The damp proof course performs a critical protective function against the ravages of rising damp. Having moisture in your walls can lead to destructive conditions like rot in timber, and spoilage of finishes like plaster, paint, and wallpapers. Worse yet, any damp material, including the mortar between bricks, can provide a home for black mould, a highly dangerous health hazard that sickens thousands yearly!
Call us, London Damp Surveys at 0207 395 5997, and we will arrange for one of our expert damp surveyors to come out and inspect your home. Based on their findings they can advise you on the best way to combat and stop the rising damp!
