Firstly by identifying the causes of the moisture. Check external drainage for leaks or blockages, check external ground levels, identify the position of the damp proof course, check seals around windows, check for damaged cills, check mortar joints in brick or stone, check for cracks through render, check for blistering paint on render, check for vegetation growth through walls. If the source of moisture is not remedied, moisture will continue to affect concealed timbers causing decay and eventual collapse of the floor. If you are extremely unlucky, it could cause dry rot, which requires a narrow band of temperature and moisture to activate, which can affect larger areas of the floor and surrounding walls including neighbours.
Damp patches in the form of circular spotting or blotches can be a sign that the outer wall coatings have failed, allowing moisture to transfer from the external to the internal wall. These patches will continue to worsen as water enters the building. This can often lead to more serious issues such as dry or wet rots which can compromise the buildings structural integrity if this issue is not rectified. Cavity wall insulation within the two leaf of brickwork can be a contributing factor to the absorption of water to the internal wall as it acts like a sponge.
PENETRATING DAMP SIGNS:
- Walls or ceilings having damp patches
- Blotches appearing on walls
- Puddles and drips
- Damp wall insulation/plasterwork
- Damp musty smells
- Crumbling and wet plaster
- Visible spores
Some forms of dampness can be prevented. Keeping on top of maintenance and regular inspections of your property – particularly after stormy weather, allows you to identify potential issues and make the relevant repairs before they advance to bigger issues.
Typically in rising damp, there is a standard specification within the industry we follow however this can differ from job to job due to the construction or layout. In general, most require us to strip the wall fabrics internally up 1-1.2m from ground level up and insert a new chemical damp proof course. Physical DPC’s are a thing of the past, as there are more advantages of chemical DPC than the insertion of physical ones. The time to install physical DPCs can be very costly, there can also be settlement and party wall issues.