Thermographic imaging is one of the most effective ways to identify air gaps, poor insulation, and leaks in a building and therefore reduce energy costs. This technology is not new, but it has been used in a different way in recent years – through the use of drones. This article explains how drones equipped with thermal imaging cameras can be used to make your commercial property more energy efficient and save you money.
Energy costs have increased considerably already in 2022 and are due to increase further still, largely due to increased demand for oil and natural gas. It is a well-known supply and demand issue that is affecting people across the world and has seen spiralling energy costs impacting business owners.
Utility bills can cost a medium sized business up to £10,000 a year and this is assuming the building is energy efficient. Consider large warehouses with poor insulation, damaged windows, leaky roofs etc. and this figure could be much higher. Clearly, it is not just warehouses that suffer these issues, many business owners are affected. As a result of increasing bills, businesses are needing to either scale back, pass on the costs to their customers, or risk difficult times.
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Is there another way to reduce energy costs?
One way a business can save money is by reducing energy usage by ensuring their premises are energy efficient. This includes ensuring their offices are well insulated, that they have the right heating and cooling systems, and that they have the right lighting. Some businesses invest in renewable energy sources to reduce their carbon footprint and lower costs. For example, solar panels can be installed on roofs to generate power for the building during the daytime or ground source heat pumps can be installed to provide heating. However, investing in this kind of technology, whilst commendable, is largely ineffective if the building is letting all the warm air escape outside.
Thermographic surveys can help your building become more energy efficient and reduce energy costs.
A thermography survey is a non-invasive, quick and accurate way to identify any issues with the building that is contributing to high energy costs. Thermal imaging can be used to find air gaps and thermal bridging in a property. Thermal bridging occurs when heat travels through a material that has a low thermal resistance, such as steel or concrete, and then into or out of the building. Air gaps occur when there is an opening in an exterior wall or roof, such as those found around doors and windows, or damaged skylights, or cracked roofing materials, for example. Heat rises and therefore it is usual for the roof of a building to be the main culprit when it comes to energy efficiency. It is also the part of the building that takes the most abuse from the weather and is therefore more likely to be the cause of leaks, which is a whole other problem to worry about on top of being energy efficient.
How does thermal imaging work?
Thermal imaging cameras, despite popular belief, do not record temperature. Confused? So was I when I started to learn about thermal imaging. Essentially, when an item heats up above ‘absolute zero’ (-273.15 degrees C) its molecules start to move around and bump into one another. This movement starts to cause friction, and friction causes infrared radiation to be emitted. We cannot see infrared with our eyes as it is not within our visible range on the electromagnetic spectrum, unfortunately. Thermal imaging cameras, sometimes known as infrared (IR) cameras records the amount of infrared radiation that is being emitted and converts that into a temperature reading.
Some materials are efficient at emitting IR radiation, such as concrete or wood, and this makes reading them with a thermal imaging camera quite simple. However, some materials are not so good, such as shiny metals, and we need to make allowances for this when we take the readings through a series of calculations.

An interesting fact about infrared radiation.
Did you know that IR waves cannot go through glass which is why a window pane will appear black when viewed through a thermal imaging camera, unless warmth is being reflected on the same side you are taking the reading?
Interesting fact number 2.
Because of fact number 1, the lens of a thermal imaging camera is made of a special material, usually germanium, which will allow IR waves to travel through in order for them to hit the senor within the camera.
Other things to consider when creating thermograms.
Firstly, in case you hadn’t guessed, the word ‘thermogram’ is the technical name for the thermal image generated by the camera. Thermographs can be affected by several other factors which all have to be taken into consideration when measuring radiant heat loss of a building envelope.
Reflection – known as background temperature. Heat can be reflected by the surface you are looking at so the time of the day that you carry out the thermographic survey is important. You ideally want to do it early morning or late evening when the sun has the least impact on your results. Luckily here in the UK it is not a massive issue as the sun can be a little bit shy, but it still must be considered.
Ambient temperature – the temperature difference between the inside and the outside of the building needs to be about 10 degrees. This is to ensure that there is enough temperature difference between the internal and external surfaces for the camera to pick up. It doesn’t matter whether the inside is hotter or colder, just so long as there is a difference. Again, early morning or late afternoon works well, or even wintertime when the temperatures outside are plummeting.
Emissivity – we talked earlier about how different materials are better at absorbing and emitting infrared radiation. This is known as the material’s emissivity value, and this is used to adjust the readings into an accurate recording.
Atmosphere – certain aspects of the atmosphere can also affect the temperature reading. Air density, humidity, air temperature, distance between the camera and the object. All these factors need to be taken into consideration.
There are other factors to consider but these are the main issues to think about when planning and executing the thermographic survey.

Where do drones come into it?
So far, we have merely touched the surface when it comes to the science of thermography and the techniques needed for it to be meaningful, but I also wanted to spend some time talking about drones.
I’m sure you know what a drone is but in case not, it is an unmanned aircraft that is piloted remotely. Drones come in many different shapes and sizes, some of which you can fly recreationally and some of which you require certain licenses and insurance to fly commercially. Drones are starting to become widely adopted in many industries to assist in various tasks, particularly when it comes to inspecting assets in difficult locations or building surveys where the best data needs to be collected from height. Combined with AI driven software a business can inspect and report on a particular asset in several minutes rather than hours or days.
Drones are also reducing the number of accidents and even deaths at work. Jobs carried out at height or in otherwise dangerous locations can be carried out by drones from the safety of the ground. With automated, repeatable, flight paths the data collected using drones is becoming the go-to standard across many industries.



What types of data can be collected using a drone?
The possibilities are endless when it comes to data collection. As long as you can connect a sensor to a drone in a safe and secure manner then the sky is the limit (no pun intended). Some examples are images, videos, ground elevation maps, digital twins, methane and other gas levels, air pollution levels, orthomosaics, point clouds, sub-terrain images, etc. We could go on for hours but the data that we are concerned about in this article is thermal data. The Zenmuse XT2 shown above is a great example of a drone thermography camera which is rich in features to get the data you need.
So how can your business reduce energy costs by using a drone and thermal imaging?
We talked earlier about the spiralling costs of energy in the UK and across the world. This trend is set to continue so businesses are looking at ways of reducing their energy bill. Business owners also have a duty of care to look after their employees so a comfortable work environment is required; they cannot just shut the heating off. This means that you need to heat up the building using less units of electricity and gas and keeping that heat inside your building has to be a main priority.
Here are just 4 ways a drone with thermal imaging capability can help to detect issues with your commercial building’s energy efficiency.
Poor insulation
Poor insulation is the biggest issue when it comes to retaining heat in a building. There are several areas in a building where poor insulation could be a problem. The number one area is the roof. Heat rises and it is your roofs job to keep the heat in and the cold out. It is also usually the largest surface area of your building, especially in a warehouse so this must be the main focus of your efforts. A drone equipped with a radiometric thermal imaging sensor can fly over a roof quickly and provide vital information about the levels of insulation beneath. It can pinpoint areas where there is little or no insulation and areas where the insulation is healthy. This alone can save thousands of pounds by not replacing or repairing the whole surface area insulation if you do not need to. Thermograms can be given to roofing contractors who can then focus their efforts on only the affected areas.
There are other areas of the building such as walls that can also be highlighted as being poorly insulated. Did you know that cavity wall insulation could start to break down after a while and sink to the lower half of the building? A thermal image might show that the top half of the walls appear colder than the lower half; this is a sure sign that the cavity wall insulation might need looking at.
In addition to this it is likely that your commercial building has heating or air conditioning ducts or even water pipes on the outside of your building, usually positioned on the roof. It is critical these are properly insulated and protected from the elements otherwise you may as well just turn your heating on and leave your windows and doors open.

Air gaps
Another cause of poor energy efficiency is air gaps. Essentially an opening between the inside and the outside of the property. These can be badly sealed windows, cracked or damaged skylights, poorly working extractor fan covers, doors with no draught exclusion or badly sealed doors, or something else. A thermal imaging camera won’t see the heat escaping from these air gaps but it will detect surface temperature differences on the surfaces directly around the area with the issue. These can sometimes appear as a wispy dark lines on the thermogram. You might be able to feel draughts in your commercial property but until you can actually ‘see’ a draught, it might be hard to detect.
Water ingress
What do we mean by ‘water ingress’? Essentially it is a leak, usually caused by damaged roof materials that allows water to creep into the sub-layers of your roof. These leaks might go unnoticed for months, even years, before you are aware of it, by which point the damage has been done. Water ingress is also bad for energy efficiency as water takes longer to warm up than most roofing materials meaning it retains coldness longer. It is true, however, that it does retain warmth for longer, but this also causes other issues such as mould, rot, humidity etc. Whichever way you look at it, a leaky roof is not a good thing. Again, an inspection with a drone and a thermal imaging sensor can collect data which can be analysed to draw conclusions about certain areas of the roof that is suffering from water ingress. These types of inspections should be carried out regularly so that early issues can be spotted and fixed before they turn into something bigger.
Thermal bridging
Thermal bridging occurs when one surface is touching another one and is transferring heat to it. This is an issue when it comes to energy efficiency as the heat could be being transferred to an external surface and then dissipated into the outside air. Thermal imaging can show bridging as dark lines on the surface on the building and can provide contractors with information they can use to rectify the issues, whether that is through insulation or creating air gaps between the two surfaces.

How much money could a thermographic survey of your commercial building save you on energy costs?
It is hard to say as there are many factors involved, however, it is clear that with energy prices increasing week on week, and are forecast to keep rising, businesses are starting to appreciate the need to ensure their buildings are as energy efficient as possible to reduce energy costs.
Some businesses in the hospitality industry recently reported that their utility bills had increased from £5,000 a year to £11,000 a year so reducing usage has to be a priority. For large businesses there are also regulations around energy efficiency that need to be taken into account. Their properties are inspected regularly and could incur large fines if they do not comply with standards.
It is clear to see that whatever size your business is and regardless of the sector it is in, there is a need to increase energy efficiency, enhance your green credentials and most importantly reduce energy costs.
Why work with us to help increase the energy efficiency of your building?
Skyball Visuals is equipped with commercial grade drones and the latest radiometric thermal imaging sensors, our drone thermography camera of choice. We love drones and we love thermography and we’re quite nifty at it.
We are licensed by the Civil Aviation Authority (CAA) to carry out commercial flight operations and we adhere to very strict safety standards to ensure that all our flights are low risk and do not pose a danger to your employees, your property and uninvolved persons.
We are fully insured with industry specific public liability insurance of at least £5m, although I am pleased to say we have never needed it.
If you would like to learn more about how we can help your business reduce energy costs, please do get in touch as we like talking about this kind of stuff!
Call us on 0800 774 7140 or use the form below and we’ll get back to you.