Dampness proof course is a very straightforward concept and a very effectual solution to a widespread problem, but it’s not easy to make clear in just a few words. The simplest way to understand a damping proof course is to visualise for a moment what would come about if a construction did not have one. We all recognise that the ground on the exterior of our home is frequently wet. Normal rainwater and early-morning dew make certain of that.
The exterior walls of our home rise straight from the ground. With nobody to stop it, the wetness would then travel through the exterior walls to the indoors, making the indoor walls moist. This would draw fungus of damp rot, and earlier than long the house would be dilapidated. All it takes to bring to an end to this wetness is a simple blockade which water cannot smash through. If moisture patches appear on the indoor walls of your home, you should at once look to find the cause. If they come into view at ground level, it is typically a sign that the damp proof course has also been smashed at that point or that moisture is somehow able to overpass that blockade, e.g. since a pile of mud has been dumped against the exterior wall, allowing dampness to travel through it and into the wall above the moist course.
In the event, if the dampness patches are higher up the indoors wall, it may be for the reason that a downpipe has been broken, permitting water to break out from it and flow against the exterior wall in a rigorous jet. If lower down, near soil level, it may be that for some cause rain is splattering upwards and hitting the exterior wall above the moist proof course. Other potential reasons take account of additional mortar and other materials having been cast off or permissible to fall between the two walls of the hollow space wall structure during the construction of the home, in so doing forming a conduit across which the wetness may pass through.
The interpretation on the exterior wall may have been enlarged down to underneath the damp proof course level, again allowing moisture to pass through the moist proof course. The same thing can take place if the plasterwork on the indoors is extended down too distant so as to pass through the moisture proof course. Or the hollow space wall ties (which join and thereby make stronger the two walls) may be inclined the mistaken way, down towards the internal wall in its place of upwards, and permitting gravity to pass moisture across the tie to the internal wall.
However, all these faults, once noticed, are usually very easily rectified, and you can once more take pleasure in living in your dwelling, free from the uneasiness of the moist outdoors. So what is a damp proof course if not a very effectual and straightforward way of maintaining your home dry and impassive by the dampness that is perpetual to be found on the outer surface.