If we raise the topic of argon gas in buildings, then we are either talking about light bulbs, double glazing or triple glazing in windows. In this article, we’ll talk about double glazing and triple glazing and the related pros and cons of argon gas in windows. The use of this gas was introduced to enhance insulation, and the principle of insulation is: The more difficult it is for cold or heat to traverse a barrier, the higher the barrier material is rated as a good insulator.
What is insulation?
Insulation is the retarding of the loss of energy, and there are different ways the energy loss occurs. For example, the movement of heat from one zone to another. There are five ways that energy can be lost, but the three we hear about most commonly in everyday life are:
- Conduction – This is energy loss or transfer that occurs in solids, liquids and gases. The transfer is a release of energy from highly charged molecules to lower charged molecules next to them.
- Convection – Firstly, this involves the movement of heated molecules. As the heated molecules are lighter, they move up, and the cooler molecules move downwards. As new molecules are heated, they move up and further apart. Convection works in gas and liquids only.
- Radiation – In this heating method, highly charged molecules release photons. This transfer can happen in a vacuum.
The benefits of double glazing windows
When talking about insulation, double glazing windows are in the top three priorities. Double glazed windows and ceiling insulation give the best return of investment in a brick and mortar building project. This has driven up the popularity of double glazing windows in the UK.
If you invest in double glazed windows and choose the option that has argon gas in the cavity between the two glass panes, then you can expect:
- 90% of the available energy will be retained on one side of the barrier.
- 10% of the available energy will travel across the barrier.
- E.g. On a fiery hot summer’s day, 90% of the sun’s warmth will remain on the exterior side of the window, with 10% making its way in. And, on a brutally cold winter’s day, 10% of that biting cold will make it into the interior.
If you invest in a triple glazed window and choose the option that has argon gas in the cavity between the two glass panes, then you can expect:
- An average of 97% of heat or cold staying on the exterior barrier and 3% managing to get through.
- It is handy to note at this point that the capital investment required for triple-paned glass windows can reach as much as 33% higher than double glazing windows. This would suggest that a pro of the argon gas with double glazing window option is that it is about 21% cheaper per percentage of insulation than the triple-glazing-argon-gas combination.
Double glazing also allows a little bit more natural light in. It’s a small difference, but it’s also a pro.
What is argon gas?
Argon is recognised as a non-toxic, unreactive (inert) Noble gas.
Argon is easily available and is therefore not expensive. It is extracted by undergoing fractional distillation when air is cooled to -189.35C. You can find argon in everyday domestic light bulbs as it allows filaments to burn at higher temperatures. And, of course, you find it in top quality double-pane windows to drive up insulation efficiencies.
Argon is also found in highly specialised equipment like medical lasers for ophthalmic corrective surgery (vein leakage, detached retinas, glaucoma, etc.) and for cooling welding areas to stop metal oxidation.
The gas is chosen for insulation because it has extremely low thermal conductivity. Whilst it is a better insulator than plain air, it is not the best available. Krypton has superior performance, but this gas’s price makes it prohibitive in use. The argon and double glazing efficiency rate of 90% is globally found to be acceptable for the return of investment achieved.
When the time comes argon gas can be replaced in windows. The window cassette is removed, re-gassed and reinstalled on the same day.
Should you consider frame material and argon gas?
When constructing a top quality double glazed or triple glazed window, the material of every component is considered. Energy efficiency ratings are driven by the sum of the related efficiency of all the parts. Frame material is a significant contributor to the performance and longevity of a window. Aluminium is a good conductor of heat and therefore a poor material for insulation. uPVC is the best choice especially in a closed back frame which prevents warping.
Is the spacer width important?
Short answer: Yes. A single spacer is used in double glazed windows as it creates the cavity between two individual glass layers. The cavity depth is scientifically optimised to achieve a sufficient cushion of air or argon gas. Undersizing or oversizing affects the insulation efficiency of the structure.
Is special glass used?
At basic level, by using two layers of regular glass, you immediately gain a better insulation performance. When you add a ‘cushion’ of air between the layers of glass, you again increase the insulation performance of the ‘multi-layered skin’.
Glass is a poor conductor of heat and therefore contributes to the overall performance of the thermal glazing equipment, i.e.double glazed windows. To leverage this insulation factor of the glass, the manufacturer can add a Low-E coating to each pane of glass. This layer filters out the infrared light that comes into contact with it, and the remaining visible light passes through to the interior of the building. The combination of heat mirror film and uPVC double glazing delivers a very high-performance insulation.
In addition, some manufacturers supply motorised blinds within the cavity which supply the screening or blocking of man-made light at night. This, by default, also adds to the reduction of heat, cold or noise that can get through the windows to the interior. A very comfortable, peaceful sleep is on the cards for the users of those interiors.
Should I consider triple glazing with argon gas?
Triple glazing windows are, by default, heavier, and the frame material therefore increases in importance. uPVC can cope with the heavier weight and live load without deforming.
Triple glazing with argon gas has gas in both the cavities, i.e. glass pane, gas, glass pane, gas, glass pane.
If you live in an extraordinarily noisy area or have extreme weather conditions, triple glazing would probably be advisable. Your window supplier can advise you if it is necessary.
Our experts are at your disposal for discussing the need for double glazing, triple glazing and argon gas in your window selection. Call us for advice today.