Damp In Your Home

Rising damp is moisture being drawn by capillary action from the ground with which the structure is in contact with.
Building materials are generally porous therefore they can soak up water in a similar action to that of a wick.

Moisture carried into the wall by a rising damp process will allow the wall to become damp.
The moisture will also pass into the joinery fittings such as skirtings, door frames and windows causing conditions in which a variety of wood rotting fungi flourish.

In addition, all soils contain natural salts, these salts combine with the moisture and are drawn up through the wall structures - usually up to around 1mt above ground level.

During the natural drying out process the salt bearing moisture in the wall is carried to the surface, whereby the moisture evaporates leaving behind deposits of these natural salts, within and upon the surface of the wall.
The salt breaks down the internal plasterwork, mortar joints and external rendering, causing them to become hygroscopic and thus capable of absorbing moisture from the atmosphere and consequently compounding the damp problem. 

This usually occurs on the external walls where the external ground level is higher than the internal floor level and consequently the moisture bearing soil allows water to pass through the wall.
It can also occur where internal floor levels vary and where the floor level of an adjacent property is higher.

Other causes of lateral penetrating damp are – abutting garden walls, paths, flower beds, fuel storage and less easily recognised are situations where the floor screed is porous or has bridged an existing damp proof course.

Obstructions causing lateral penetrating damp should be removed otherwise the walls must be waterproofed by applying an impermeable surface.

TDT offer a separate Structural Waterproofing/Tanking service. 

This is often caused by defects such as porous window cills, string courses or masonry.
Roof defects, leaking or blocked or undersized gutters and downpipes will also contribute to this commonly encountered problem.

Occasionally cavity materials will form the necessary bridge across a wall to allow water penetrating on the external skin to adversely affect the internal wall surface.

Regular building maintenance is important. In some circumstances the application of external wall treatments can assist the eradication of such problems. 

This manifests itself as surface moisture and is often prevalent on hard impervious surfaces such as gloss paint, tiles and vinyl wall coverings etc.

The amount of water vapour that air can contain is limited and is known as relative humidity. When this reaches saturation, known as the dew point, saturated, condensation will form on surfaces within the building.

The saturation point will vary with the temperature and the amount of water to be vaporised is dependent upon many factors.

The control of heat, extraction and ventilation all help to reduce condensation problems.

TDT can offer advice and systems of which can control these situations.