Thermal imaging investigation raises puzzling questions

by Blog

Andrew Gage reports on the experience of borrowing the thermal imaging camera.

My reason for borrowing the camera was to check the effectiveness of the insulation in our house. We began work on the house after its purchase in 2010. I knew about the importance of insulation before the work began, but only had limited knowledge about other environmentally friendly technologies. I supplemented this by in-depth consultation with Manchester Energy Saving Trust.

However, our task was complicated by there being 3 eras to cope with – the original building was 85 years old; an extension added by the previous occupant 10 years before; and the extension that we intended to add.

We employed an insulation company (Dyson) to survey the original house, which had a 50mm cavity and they injected insulation into that and relayed the loft insulation to 28cms. I assumed that the 10 year extension would have been insulated in accordance with Building Regulations and knew that the new extension would be correctly insulated because I was project managing the process.

The original house had a suspended floor and a crawl space that allowed loft insulation to be inserted between the joists. The existing double glazed windows were replaced and triple glazed windows and patio doors installed in all the new build.

On completion of all work and installation of solar p.v, an air source heat pump and a rainwater harvesting system, we joined SuperHomes and they assessed the house and decided that we had reduced our carbon output by 74%. Subsequently we have opened our home to visitors on several occasions and I have emphasised the importance of insulation.

I am not very efficient with new technology, so the thermal imaging camera was a challenge, but it seemed to work and I produced the images that can be seen. The outcome has been concerning. It appears that there are several areas that are not as well insulated as I thought, in particular the windows and an entire wall in the 10 year old extension (see below). I am now puzzled and concerned. Are the images accurate; is my interpretation of the results incorrect; what should I do now?

I intend to ask the insulation company to return and check the rear wall that appears non-insulated. I held a long and informative conversation with Thermal Imaging Services, based in Marple, and realized that my results are almost meaningless, compared to the extensive service they provide. However, it will cost £495 and for that I receive a comprehensive report, detailing what they have identified, what they think is causing any leakage of heat and suggest remedies that are worthwhile.

However, we live comfortably, and apparently draught free, in a house which is warmed to a minimum of 18.5 degrees, but hotter if we choose, 24 hours a day, for 365 days a year, because of the heat pump. Our energy costs are about £300 p.a. for a large detached because of the feed in tariff. Why bother – conscience, frugality, a need to get it right? The answer to that question will be revealed at some point in the future – but I am open to suggestions.