Can you carry out thermography surveys of buildings when it is raining?
I have often been asked this. If it rains, the external surfaces can be wet/damp. This causes evaporative cooling over the damp surface and this cooling can mask problems. For this reason it is best not to conduct surveys in the rain. Reports should not how long since the last precipitation. It is good practice to leave surface that have been exposed to rain for at least 12 hours since the last rain. As an alternative you should not survey the outside of the building and limit the survey to the inside of the building only. It is surprising how many companies conduct external building surveys when it is still raining, companies that operate like this should be avoided. A few years ago I was finding it difficult to schedule a survey due to a bad period of weather. After the weather cleared up I contacted my customer who told me that it was done, he found a company based in Laois that said their camera worked in the rain. While it is certainly true that their camera worked in the rain, they were either not being completely honest with the customer, or they did not understand thermography.