Damp Proofing

What causes damp?

Rising Damp
Rising Damp is a blight that can affect external and internal walls alike. The source of dampness in this case comes in from ground water. The bricks and mortar in the dry upper parts of the wall acts like a wick and draws water upwards. Well maintained, well-constructed walls will have an efficient physical damp proof course (DPC) and are unlikely to possess dampness unless the damp proof course has in some way been compromised, for example;
● A Compromised physical DPC due to age and/or original use of poor material
● External materials ie soil, shingle, rubbish against the external wall below and above the DPC.
● Existing DPC breached by home improvements ie addition of a porch, conservatory, adjoining wall etc.
● Materials within the cavity of a cavity wall construction
Once the damp proof course has been compromised remedial action is required as soon as possible.
Continued presence of dampness on the upper walls will lead to deterioration of brickwork and internal plaster and décor.
The internal plasterwork in the home can break down quickly when exposed to such dampness.
Replacement of plaster is usually required to some degree.
Salt contaminated plaster should not be left in place, it will continue to absorb moisture created in the home and will frustrate attempts to correct the wall décor.

Identifying Rising Damp

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Damp patches to external walls as shown may exhibit significant moss growth on external
brickwork, water staining etc. Dampness may also be felt and seen on internal walls of the property, moisture and salt bands are common signs to
look for.

All these conditions may of course not be due to rising damp, they could be the result of a simple water leak due to poor guttering, roofing etc. Which results from the property suffering from penetrating damp.
Rising damp, is where water is drawn up from ground level by capillary action, the
nature and physics involved with this form of dampness means it will rarely be present more than 1
metre from ground level. Signs of dampness above this level are commonly seen but will most likely be the result of condensation or penetrating damp.

A professional remedial survey is highly recommended in such cases as mistakes in diagnosis can result in unnecessary and costly work that fail to control the dampness.
Plastering Solutions provide free surveys and reports, with impartial, honest advice on the
options available to the customer.

What is Condensation?
The amount of airborne water or water vapour in the air will vary with the temperature. The warmer the air is, the greater its water-holding capacity. The warmer the air the more water vapour can be held and the cooler the air the less water vapour can be held.

Within a building, the air is usually warm and can hold a large quantity of water vapour without there being any significant problems, however when it is cooled such as when it becomes in contact with a cold surface (such as a window or external wall), the excess water can no longer be held in the air as a water vapour condenses as water on walls, windows or any other cold surfaces.

Condensation is one of the most common causes of dampness in the domestic environment. The majority of the time it is caused by warm, moist air from everyday household activities such as cooking, washing, bathing, or even just breathing creating an overload of moisture in the air which subsequently condenses onto colder surfaces in the home such as walls, window and ceilings.
This figure can be greatly increased if you:
A. Dry clothing indoors or on radiators.
B. Use unvented tumble dryers or portable gas heaters
C. Don’t ventilate the room when cooking or having a bath or shower.

How do I know if I have a condensation problem?
A clear sign of a condensation problem is water streaming down the inside of windows, particularly bedroom windows in the morning.
Mould growth on walls and ceilings beneath a bay window, behind furniture, under a bed or behind wardrobes. This mould growth can be virtually any colour, with the most common being black, green or brown, but there are a variety of colours.
An earthy or musty smell, particularly if the house has been empty for a while. This could be if you have been away for a day or so.
Shoes and clothes in wardrobes can smell musty or have mould on them. Damp patches appear on plaster in ‘odd’ places, particularly on outside walls. These patches can appear and disappear on a regular basis.
When and where does condensation occur?
Condensation can occur at any time, but it is more likely to occur at night because the air temperature falls, which conversely can cause a rise in relative humidity.
As surfaces in the home become colder there is an increased likelihood of condensation forming, especially on windows or external walls.
Fortunately, there are ways of controlling condensation and that is where we can assist you.
We can offer a variety of solutions to your condensation problem.

We offer a full supply and fit service for a range of Extractor Fans, Positive Input Ventilation, Heat Recovery Fans, and Humidistat Controls
PIV ventaltion system

Plastering Solutions provide free surveys and reports with impartial, honest advice on the
options available to the customer.

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Damp proofing areas covered- Glossop, Ashton, Hyde, Oldham, Manchester, Stockport, Altrincham, Sale, Trafford, Sheffield and Barnsley.