Damp within properties falls into three broad categories, Rising Damp, Penetrating Damp and condensation.
The ground contains water and this water can be drawn up into walls via capillary action. To prevent this water being drawn up into the walls, buildings were and are still built with a Damp Proof Course. A Damp proof course is made of many materials from lead, bitumen and slate to modern plastic. Often the Damp Proof course can be bridged by other building defects or over time can deteriorate and fail.
To renew the failed Damp proof course, it needs to be correctly diagnosed by a competent surveyor and a specification produced for remedial action. The type of system to be used would also be specified as would re-plastering and other works to ensure a successfully solve the rising damp and produce a guaranteed solution.
Resolving rising damp is the costliest of processes and if miss diagnosed could cost thousands of rectify or be wasted on unnecessary treatments. This is a major issue with damp diagnosis
Damp penetration is exactly as it is described, when poorly maintained or damaged external fabric of a building allows excessive water to hold and then damp penetration of the building occurs into the building internal surfaces and results in damp walls and condensation.
These issues are caused by defective rainwater goods, leaking roofs, failed pointing or render. Repair or renewal of these is essential to returning the properties internal surfaces to a suitable environment in the living areas.
Penetrating Damp can be mistaken for rising damp if not correctly diagnosed.
Internal burst pipes, leaking showers and such like are referred to as an escape of water and should usually be referred to your insurers.
Often the tell-tale signs of mould growth will allow condensation to be diagnosed quickly and effectively. Moisture produced in a property may be excessive for the ventilation within the dwelling and build u in the fabric of the structure.
It can be misdiagnosed as rising damp quite easily. If correctly diagnosed the recommendations can be implemented relatively inexpensively and quickly.
A competent trained surveyor can diagnose damp issues and separate the Rising Damp from Condensation issues and Penetrating damp. This can usually be achieved with none destructing moisture metre tests, where there are a number of issues it may be necessary to carry out destructive testing and sample analysis.
A qualified surveyor would discuss this with you before proceeding. You should check the experience and qualifications of the surveyor employed. Most professional companies will offer this type of information within the report provided.