Independent investigations into your home's damp problems with impartial advice on dealing with them
As an independent Surveyor and Damp Consultant, I can investigate your damp concerns. A proper investigation will enable me to give you the reassurance and advice you need, helping you avoid unnecessary and inappropriate building work.
There are many different causes of damp and it is common to find a single damp problem has several causes. There are therefore many solutions to damp and a combination of these is often needed to deal with a single problem. Houses can also vary dramatically in their structural design and the materials they were built with, as well as being altered over the years. This means the solution for any given cause of dampness needs to be tailored to your individual home in order to be effective. Only by getting to the root of the problem and confirming the type of construction, is it possible to work out the best course of action.
To enquire about a damp investigation on your home, ring me on 01263 734815 or fill in the enquiry form below.
To give you an idea of the range of problems, the following is a small selection of some of the more common causes of damp:
- Render made with Portland Cement which has subsequently cracked and started to separate from the backing wall. The defective area of render can be some distance away from the damp area – in the picture below, the damp was being caused by cracked and separating render on the outside of the wall some 3 to 4 feet (1 – 1.25 metres) above the damage.
Severe damp below an area of cracked Portland Cement render
- High flower and shrub beds against the walls of the house. This is frequently misdiagnosed as a damp proof course failure. The damp in the picture below was caused by a very modest and pretty rockery that had been built against the house a few years before the damp appeared.
Severe damp in a wall backing onto a small rockery
- Too much or too little ventilation. This is often accompanied by insufficient heating or the wrong pattern of heating for the type of house. In the picture below, the wallpaper has come away from the bottom half of the wall and black mould has taken hold because of a combination of over ventilation and under heating.
Mouldy wallpaper coming away from a cold wall surface
- Exterior walls of the house painted with ordinary masonry or gloss paint in which tiny imperfections have formed. This situation can make certain types of wall extremely damp.
- Leaking pipes hidden under floors or buried inside walls. These can go undetected for years, especially if hidden behind ceramic tiles. The picture below shows a bedroom wall backing onto a fully tiled bathroom in a bungalow – a pipe had been leaking for years under the bathroom's tiled floor, gradually saturating the adjacent hall and bedroom walls, yet is only just becoming visible as a darker band at the bottom of the bedroom wall.
Water leak starting to appear as a damp band at the bottom of the wall
- Nails or screws in the outside of the house walls. These can produce individual damp spots similar to those produced by incorrectly installed cavity wall ties.
- Chemical contamination of wall plaster by soot, tar and flue gases. These chemicals come from chimney flues that are either unlined or where the lining has decayed. In the room pictured below, the contamination has become so bad, the damp has spread across the top of the chimney breast into the alcove and is starting to spread over the ceiling. Cases like this are commonly misdiagnosed as leaks around the chimney.
Damp spreading across the chimney breast into alcoves and over the ceiling
The investigation of your damp problem typically involves the following stages:
- An initial visual assessment to determine the likely extent of the investigation. This will also indicate specific areas of the house likely to be needed for access e.g. lofts, adjacent rooms etc.;
- Photographs using flash lighting to highlight the full extent of any staining or darkening due to damp. As well as detailed close-ups, more general views are also taken to place the problem areas in context;
- Sweeps of the area using a selection of complementary types of electronic moisture meter: for instance, a microwave moisture meter can detect moisture below the surface to a depth of 12" (300mm), and is not affected by salts, while a capacitance moisture meter can detect moisture in greater detail at the surface, and to a depth of about 1½” (40mm), but is also triggered by salts. Any variations found are plotted to see if they form a pattern across, up, or through the wall, that indicates the likely presence of excess moisture within the building fabric. This is called a moisture profile;
- Use of an electrical resistance moisture meter, to probe any timbers in permanent contact with areas that produced high readings during the previous meter sweep. This reveals the moisture content of the timber, it is this that usually determines whether or not the building fabric has a serious damp problem;
- The air temperature and relative humidity in the vicinity of the damp are measured. The temperature and humidity are then used to calculate the dew point within the room – this is the surface temperature that triggers moisture to condense from the air onto any surface;
- Where condensation is suspected, or internal and external temperatures differ sufficiently to enable hidden timbers in outside walls to become visible in thermal images, photographs and visual checks are made with a thermal imaging camera. The camera gives the spot temperature of the surface being viewed, and reveals any variations in temperature of adjacent areas. These differences can be caused by different materials within the structure, variations in the moisture content, or differences in the immediate environment surrounding the area being viewed (e.g. the presence of cold draughts, or variations in warm air currents);
- Cross referencing of the thermal images against the moisture profile. This helps to identify any anomalies (environmental or within the construction) that may be contributing to the problem;
- Measurement of the positions of possible damp sources so they can be checked on the other side of the walls/ceilings/floors;
- Sometimes the above stages need supplementing with the lifting of floorboards or opening up of some part of the building to obtain further information;
- The final stage is to collate and analyse all the information. This will establish the relative importance of the various causes identified, the constraints imposed by the building, and the likely success of the possible solutions.
The cost of an investigation into those worrying damp problems currently affecting your home, is £400 for up to 4 hours. This covers most investigations. For larger properties or more complex investigations, any additional time needed for the investigation, is charged at the rate of £75 per hour. For all investigations, the only other chargeable cost is my travel expenses, which of necessity vary by location. Travel expenses include a contribution towards my time, and are calculated on mileage for the round trip as estimated by the RAC. As an indication, travel expenses are around £15-20 for parts of North Norfolk and Norwich, and around £200 for locations in and around Greater London. There are no other charges – I am not registered for VAT, and don't charge for postage, or reports, etc.
Misguided attempts to cure your problems without the proper investigations can easily result in unnecessary expense through inappropriate building works.
Damp investigations are available throughout the East of England, Midlands, and the South-East. As the investigation of your damp problem involves assessing its severity, extent and causes, this can often take several hours. Afterwards, when all the findings have been properly analysed to allow an appropriate action plan to be devised, you will receive a report which includes recommendations specific to your home for dealing with the damp.
To enquire about an investigation into your home's damp problems, ring me on 01263 734815 or fill in the following form:
Privacy Statement - Your name and contact details will be held in the strictest of confidence. I will not under any circumstances share this information with any third party, unless I am compelled by a court order.
About David M. Kinsey
I am an independent Surveyor specialising in damp and its associated problems, particularly with regard to older houses. Based in Norfolk, I am regularly called upon to carry out investigations for clients throughout the East of England, Midlands, and the South-East.
My building surveying career dates back to the late 1970s. I have also been a Chartered Information Systems Engineer since the mid 1990s.
In recent years, there has been extensive (and ongoing) research into moisture in old buildings, and major changes in modern building construction. To keep my knowledge up to date, I subscribe to specialist technical publications, and attend a variety of courses and seminars. These are run by organisations such as the Society for the Protection of Ancient Buildings (SPAB), the Institute of Historic Building Conservation (IHBC), the Building Research Establishment (BRE), the Building Limes Forum, and the Institute of Specialist Surveyors and Engineers (ISSE).
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