Thermal Imaging for damp inspections

The use of thermography for damp inspections has become an increasingly popular topic over the last few years with many good organisations such as the Property Care Association and National Flood School both offering Introduction to thermography sessions to demonstrate the use of thermal imaging technology in the damp proofing and restoration industries.

With advancements in technology manufactures of thermal imaging equipment have been able to produce cameras at a much lower costs making them more affordable and as such, their use has become more and more popular. Recently Flir Systems have launched their new Flir i3 Thermal imaging camera, the first camera sold for under £1000.00 and the new Ebx Series for building inspections at approximately £8000.00.

With the costs involved in buying a good thermal imaging camera inevitably its purchase is a long term investment for which you will have to select the right camera for your applications and budget. As budget is always going to be a primary concern it is important to remember that with lower cost cameras their is inevitably a reduction in quality and performance of the equipment, more often this sacrifice in quality is aided by clever little gadgets and facilities, which whilst nice are not essential.

The much lower budget i3, i5 and i7 cameras are ideal for electrical and mechanical maintenance and even enthusiastic homeowners, however, their use as a building diagnostic tool for surveyors is limited, this refers back to the quality and sensing capabilities of the camera. The sensitivity and quality of the IR detector is what matters in achieving a good quality image, the fewer infrared pixels, the lower the quality of image you will receive. This can result in the detail of an image being reduced or lost completely especially with the cheaper cameras which auto focus.

When looking at specifications and prices for cameras it is easy to be fooled into thinking cheaper cameras may do the same job as the more expensive cameras, this is simply not true. Be careful not to confuse the display resolution of the camera with the resolution of the IR Detector, often manufactures will display the higher LCD display resolution leading you into thinking you’ll receive excellent quality images meanwhile the sensing capabilities of the vital IR detector are much lower. Inevitably, the poorer image that your camera displays the better thermographer you’ll need to be to interpret the image results.

As you can see from the images below, the image to the left was taken with a low resolution camera in comparison to a high resolution image on the right, and you can see how the detail of the image is lost. Over looking a building with a wide field of view, its not likely to make much difference, however when looking at a property in detail, when the clarity of the image is lost this may result in omissions being made.

Whilst its apparent thermography has many benefits to surveyors working in our industry, offering another non-invasive technique of assessing buildings and materials which may or potentially be vulnerable to decay and dampness. Like many other tools in a surveyors tool kit, however a thermal imaging camera must be used by a trained thermographer as images just like readings from an electronic moisture meter can be miss-interpreted. Even the most expensive of high sensing thermal imaging cameras is only as good as the operator using it, and in the hand of an idiot miss identification and diagnosis can occur.

It is therefore essential that if you buy a thermal imaging camera you also budget for the training needed to use it properly. The ITC (Infrared Training Centre) are the Global Leader for Infrared Training and their courses and qualifications are essential to anyone who wants to use thermography as a tool for inspections.

Beware however, the price of the training to become a qualified L3 thermographer can be up to £5000.00 much more than most would even consider paying for the camera itself. I hesitate to say that unfortunately, this may mean the majority of camera owners fail to train themselves properly in its use.

We’ve been using our thermal imaging camera successfully for years and our surveyors are qualified and trained in thermography. If you need help in accurate inspections and diagnosis, don’t gamble call the experts; Dryfix Preservation Ltd  “Yorkshires Leading Damp & Timber Specialists” on 01904 791388 or visit our website www.dryfix.net

Russell Rafton C.S.R.T / A.Inst.SSE
Dryfix Preservation Ltd – Surveyor