Damp Survey Service

Here is a classic case of rising damp. Unfortunately it is not always so easy to see as it is here. The tidemark arises due to the contamination of the plaster and wallpaper by minerals dissolved from the ground and deposited by the damp as it rises. We see it in this image because the decoration is so very old. Often, repeated re-decoration renders the stains invisible; however modern moisture meters allow a ‘moisture profile’ to be obtained, which reveals the tidemark.
Here is more staining, this time made by mould growing on a damp wall. This is not rising damp. The mould is growing on a physically wet wall, in this case due to condensation. This is a house in north Leeds, modernised to make a rented apartment. Unfortunately the developer was not well informed; after bricking up the fireplaces, installing double glazing and sealing all vents – he didn’t install extractor fans into the kitchen or bathroom – this was an inevitable result – be thankful you can’t smell it.
One way of finding the source of moisture is a simple salt analysis – in this case the red colour indicates nitrates are present. Nitrates are derived from the decay of organic compounds; the ‘Nitrogen Cycle’. Salts only move in solution, so accumulation of nitrates in say – a plaster sample, indicates movement of moisture from soil. Salt analysis can be useful, but is not definitive and requires careful evaluation, taking site conditions and history into account.
<strong>The Protimeter Moisture Measurement system.</strong> Bryan’s favourite toy - a clever, if expensive box of tricks, incorporating: a conductivity meter, radio frequency meter, temperature and thermo-hygrometer attachments. Internal software calculates the dew point of the measured environment and when used with a psychometric chart, vapour pressure can be calculated. Deep wall probes, hammer electrodes and data recording PC download functions, are used with this too. Fast and useful in the right hands, though not a tool for beginners; as with all electrical moisture meters, the results must be interpreted properly.
<strong>The Speedy Meter.</strong> This is the business end of our ‘speedy’ chemical moisture meter. Whilst is it more accurate than an electrical conductivity meter and gives a quantitative reading, it is a destructive method, requiring plaster or masonry samples. It is slow too, needing ten minutes per sample – an electrical moisture meter can thus obtain a decent, though qualitative moisture profile, in a fraction of the time. However, by taking large samples and dividing them in half, gravimetric testing can be used in conjunction with this tool, allowing separation of ‘free’ capillary water, from moisture chemically bound by hygroscopic salts. This is then compared to the ‘air dry’ moisture content of the sample, confirming whether capillary moisture is present or not. This is not possible using an electrical meter.

Damp Surveys

Damp is a four letter work nobody wants to hear. We all use it, but it can mean so many different things:

  • Stained walls and ceilings
  • Salty brickwork and plaster
  • Peeling wallpaper
  • Musty smells
  • Rotten skirting boards and
  • …mould.

In fact, all of these are just symptoms, caused by moisture being in the wrong place and in excessive amounts. Damp may also be present in buildings, without any discernable symptoms, accumulating below floors, in voids and behind plaster, where it can be a real problem, causing hidden damage to in-built timbers and encouraging insect attack.

This is where qualified remedial surveyors are so valuable, particularly to anyone buying or renovating a house or commercial building. We are trained to find these problems efficiently and Bryan and Jeff have decades of experience, surveying everything from humble back-to-back terraced houses to stately homes, barns, hospitals, universities and mill buildings – we’ve seen them all.

We seek damp out and identify the cause of the problem accurately. Rising damp, Penetrating damp and Condensation are the three most common sources of moisture. However, there are many more than three reasons why these problems may be present and it is important to treat every building on its own merits – we find that no two houses are the same, those on the same street or even next door to one another will differ.

Whilst knowledge and a good pair of eyes are our best tools, we also employ advanced moisture meters, with data logging, salt analysis and deep moisture probes when needed.

Our written damp reports are detailed, with well explained content, using digital photographs when required. Our reports are exceptionally credible, because of our qualified status and our subscription to the Property Care Associations code of ethics. We can also issue PCA certified reports where these are needed by lending institutions or are required for your own peace of mind.

We don’t survey for free, which means that we don’t need to sell you anything, to pay for our time. Domestic and commercial damp and timber surveys are available from only £60.00, which includes VAT. Reports are always issued in writing, with a digital copy sent by email upon request. Same day issue, transmitted from site to office and on to you is also available for an additional fee. Please contact us for a damp survey by either Bryan or Jeff.

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