5 quality factors to look out for when buying triple glazing

The need for a greener environment has become a priority not just for the government, but also for concerned citizens. Reducing your carbon footprint is every citizen’s responsibility and it has to begin at home. It is only possible when we start using less energy-hungry appliances and increase energy saving with home upgrades and other efficiencies. One of the most popular energy efficient upgrades, is to replace old window systems with energy efficient triple glazing.

Triple glazed windows are durable, long lasting and highly thermally efficient, which decreases energy use and at the same time increases the market value of the property. However; to get the most value out of your new triple glazed window, it is also important to pay attention to the quality of manufacturing and installation.

Not all triple glazing windows are made equal, but knowing which attributes to look out for can be challenging. A window that is not sufficiently sealed during production or manufactured from inferior materials will not give you the thermal barrier as advertised and therefore not the cost saving and heat retention benefits.

An improperly manufactured and installed window will soon start showing signs of failure: condensation, cold spots, leaking insulating gas and draughts are all signs of a substandard window.

Here are the 5 things you need to look out for:


1.   The Manufacturer

The manufacturer should be registered with FENSA, BM TRADA or Certass and should be able to provide you with an insured guarantee on the work. They should also be able to provide verifiable testaments from other home owners who they have done work for over the years. A registered manufacturer and installer will make the process of replacing windows easier by saving time and cost. The guarantee, which can be anything from 5 years to a lifetime guarantee on frames, will also protect the consumer from faulty workmanship and installation.

2.   Environmental and safe business practices

It is necessary to confirm that the raw materials used in the manufacturing of the windows are responsibly sourced, that waste is kept to a minimum and that there are no toxic byproducts. Though European regulations ensure that safe practices are followed, it is good to check that the manufacturer complies with these practices.

The British Standards Institution (BSI) has some standard requirements that all raw materials for manufacturing in the UK must meet with. Glass is one of the major components of triple glazing and the flat glass companies in the UK have good health & safety, environmental, and quality & supplier management systems.

3.   Window Energy Rating (WER)

All domestics windows in the UK have been rated by the British Fenestration Rating Council (BFRC) since 2004. In recent years, both Certass and the BSI have also set up their own window rating systems, which means window manufacturers have a greater choice of which certification body they would prefer to register with. The rating is based on the energy efficiency levels achieved by the manufacturer, rather than each individual window unit. The WER ratings range from A++ to G with the minimum rating required being C. Different factors like U value (rate of heat loss), G value (solar energy transmittance) and L value (air leakage) as well as R-value (resistance to heat transference) are measured to arrive at the WER. Ensure that your windows are at least A+ rated. Only triple glazed windows achieve the BFRC A++ rating, proving their superior thermal efficiency.


4.   The different Types of frame material

The different frame materials used for triple glazed windows increase or decrease the cost of the window and also affect its quality and durability. An improperly fitted frame will require frequent maintenance and also increases the chance of window failure, where the gas between the window panes escapes, lowering the thermal resistance of the insulated unit. A good frame will provide a perfect seal around the panes that will not allow gas to escape.



The cheapest window frame material on the market, it is also the most versatile and durable material for upgrading windows. Good quality PVC has low thermal conductivity, is strong, long lasting and easy to maintain. Since PVC is easy to mold, it is also possible to form windows in any desired shape, form and color. Since this material is cheap both in terms of initial cost of manufacturing and subsequent maintenance, PVC is considered better than timber in terms of energy efficiency and cost. Unlike timber, it does not rot, warp or fade. It is also fireproof and water resistant.



To prevent thermal loss usually associated with aluminium, modern aluminum frames come with multiple chambers and thermal breaks to counter its conductive properties. It is also light weight and durable. Good quality aluminum is resistant to corrosion and needs little to no maintenance.



This natural material that has been favored over the ages for window frames, has the lowest thermal conductivity and hence is a great material in terms of energy efficiency. However; it is not as versatile as the other materials in terms of color and finish. It also requires more initial cost in terms of manufacturing and subsequent maintenance. Wooden frames need to be of good quality and sustainable wood sources. Cheaper timber frames could be susceptible to rot sooner due to wet weather conditions and can cause failure of windows. It continues to be the most popular choice because of its natural beauty, durability, and classic good looks. To get the most environmentally friendly windows, consumers should ensure that the wood is sourced from sustainable forests. By choosing a natural finish, you can also reduce maintenance, cost and environmental impact.


Aluminum-clad wooden frames

Aluminum cladding is done on the outside of the wooden frames that are exposed to the elements, while keeping the warmth and beauty of a wooden frame intact on the inside of the house. This frame combines the characteristics of aluminum and wood to give a highly durable and long lasting alternative.


Commonly used spacers are single seal spacers, warm edge spacers and premium spacers. The single seal spacer has not been found successful in giving good results for insulation, while the warm edge spacer is able to maintain its flexibility through different climatic conditions and temperature changes. The premium spacer is made of high grade silicone, resistant to oxidation by UV light. It is not only durable, but also effectively retains the gas within the panes thus increasing its efficiency.

Compound sealant is used to seal the unit around the edge of the glazing to the back of the spacer. This also ensures an air tight finish and overall strength to the unit. Some of the sealants available are Polysulphide, Silicone, Hotmelt, and Polyurethane.



While Argon [Ar] gas is best suited for double glazed windows, Krypton [Kr] gas has been found ideal for triple glazed windows. Krypton gas is a better insulator than Argon gas and works more effectively in smaller gaps, enabling the reduction of window pane spacing in triple glazed windows. Although Krypton gas is more expensive, it is definitely the better gas to use in triple glazing because of its increase thermal resistance.

It is easy to be misled in a market where there are many window makers all claiming to be the best, so it is necessary to do a complete analysis of the type of materials and credibility of the manufacturer to be used for the window that will best suit your climatic conditions before investing your money.

Look out for manufacturers with proven track records on whom you can safely rely for perfectly installed, insured windows that improve your home environment with ultimate performance and value for money.

Published on : 27th February 2017

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