Saturday, 16 February 2013


MYTH- uPVC Door/Window are sound & dust proof or, noise insulating?

Fact  :- That's not true ! Not all uPVC Door/ window are sound or, dust proof ( By the way there is nothing as 100% proof ; we can have noise & dust resistant not noise proof )...specially worth mentioning sliding windows/doors which always has leakage as shown in below mentioned picture

Right now in India, there is no Door/Window rating council( as in U.K.-bfrc) otherwise all manufacturer has to mention their air leakage via door/window in written as below mentioned pic says-

Sharing quite laughable ad from a famous uPVC Door/Window Brand in India........( Noise insulation via Sliding Doors !)

MYTH- White uPVC windows may turn yellow?

Fact :- Over the years we’ve heard all sorts of strange comments regarding uPVC windows and doors. I think the most popular one was “they go yellow” after a few years. If the upvc windows is made for Severe or, Extreme weather as per International Standards( any standards equivalent to EN 12608-2003, read more..), It will never turn Yellow or, color fade in tropical country like India & lasts as long as Building lasts i.e. 40-50 years.

MYTH- UPVC Windows and doors are costlier than wooden or, aluminium windows & doors ?

Fact :- This is not True – UPVC windows & doors profile systems are not costlier than high quality wooden & aluminium windows profile systems. Its high end fittings makes it costlier than wooden & aluminium windows. e.g Multi point locking is not available with wooden & aluminium windows.( check Video)

It has longer life span than wooden or, aluminium doors & windows. so if you compare pricing of upvc profile systems than compare it with good quality wooden & aluminium profile systems.You will find it is cheaper but Quality fittings makes uPVC costlier as compare to wood or, aluminum.

MYTH – UPVC Windows & Doors are not fire safe?

Fact :- Many people have questioned the safety of upvc windows & doors. In an unfortunate situation where a fire occurred in a home, just how would upvc windows affect the amount of time needed for proper evacuation of the living areas? There are many worldwide building codes that require windows to be of a certain minimum size. This minimum size is the area of opening required for fire fighters to safely enter a dwelling with a life support system mounted on their backs. These codes cover all types of window systems (wood, aluminum, steel, and upvc) and are all understood by builders, contractors, and remodelers. These codes were designed for the safety of homeowners and their property in the unlikely event of a fire or mishap.

Many studies have been conducted that evaluate the amount of harmful gases released from the combustion of various materials used in the construction of a home and in the manufacture of furniture, curtains, rugs, etc. Most agree that limiting the amount of gases and by-products released from the combustion of these products is the main factor that will ensure a safe and timely evacuation from a burning area. A test performed at the University of San Francisco evaluated many of the products used in a typical American home. Various materials were tested and the results were stated in the amount of time the material burned to cause incapacitation and death to the occupants in an enclosed area. Surprisingly, cellulosic materials (wood and cotton) performed very poorly while wool and silk were found to be the most toxic material tested. On the other hand, PVC performed quite well. PVC allowed almost 10 percent more time to evacuate a dwelling than wood and twice as much time as silk, cotton, and polyester. These results show that the acceptance of wood and fabric used in the construction and decoration homes, reflects the fact that upvc is a readily accepted and safe material for use in the construction of fenestration (window and door) products.

MYTH – Double glazed glass provides good acoustic or, sound insulation?

Fact :- Most architects and specifiers in India believe that insulated glass provides a good acoustic shield. This is NOT TRUE. In fact a 6mm+12mm air gap +6mm insulated glass provides less acoustic insulation than a 12mm monolithic glass at most frequencies. Laminated glass on the other hand provides far superior acoustic insulation when compared to insulated glass; as much as 5-12dB extra-protection over low frequency range, which is the traffic-zone.

MYTH – Toughened or, Tempered glass works as a security glass?

Fact :- Toughened glass can be a safety glass but not a security glass. Safety glass means preventing accidents and injuries due to accidental impact as well as from falling through glass.

                                                           Break Pattern of Annealed Float Glass

Properties of Toughened Glass-

• 4-5 times stronger than Annealed (Raw) glass of the same thickness.
• Can resist thermal stresses as edge strength is higher.
• Breaks into small blunt pieces providing safety (fully tempered glass is a safety glass)
Toughened glass is considered to be a safety glass if it meets the relevant break pattern criteria; these criteria are set out in standard EN 12150, which also describes the test to be carried out to ascertain this break pattern. The table below shows the minimum number of pieces into which this glass may break in a window measuring 50 mm x 50 mm. In addition, the length of the largest fragment may not be more than 100 mm.

Security glass means protection from outer world i.e. against vandalism or, against fire arms or, against explosions.( Please check below mentioned video)

MYTH – Reflective Glass is like a Mirror and can be used for privacy in a house?

Fact : – It is not true- it is important to maintain privacy by preventing people from looking into a room. Heat reflective glass: this partially obscures a room from prying eyes provided that the room in question has a lower light level than the environment outside.

Principle lies " wherever low light , people will feel privacy" as shown in below picture.. During day,You can not see through in this  IFCI building at Nehru Place, Delhi but in the late evening or, night, you can see through glass as outside light level is low & inside light level is high.

In place of Heat Reflective glass, one can use two-way mirrors: these are glazings which allow vision in one direction only to enable those inside to see out, but prevents those outside from seeing in (airports, large shops, etc.). Two conditions are required for good two-way mirrors:
  • a coated or, in common language Reflective glass( Having High External Reflection than Internal Reflection) must be used with a low level of light transmission.
  • the glass used must have a much lower level of luminosity on the viewing side than on the viewed side.
MYTH – I am using double glazed glass at my Home but I see water drops on inside pane of glass-Is my window leaking ?

Fact :- To understand this problem we need to understand condensation.

What is condensation?

Condensation is defined as the physical process by which a gas or vapour changes into a liquid. If the temperature of an object (e.g. grass, metal, glass) falls below what is known as the ‘Dew Point’ temperature for a given relative humidity of the surrounding air, water vapour from the atmosphere condenses into water droplets on its surface. This “dew point” varies according to the amount of water in the atmosphere (known as humidity). In humid conditions condensation occurs at higher temperatures.In cold conditions condensation occurs despite relatively low humidity.

Indoor condensation

The principal cause of condensation on glass on the inside of a building is a high internal humidity level coupled with a low outside temperature which cools the inside surface to below the dew point, particularly around the edges. Bathrooms, kitchens and other areas where humidity levels are high are particularly susceptible to this problem.

Ways of controlling indoor condensation :

In order to control this form of condensation, consideration should be given to improving the heating and ventilation in these areas. However, another way to reduce the problem is to use high performance double glazing window containing an enhanced thermal insulation glass.Windows manufactured using an energy efficient low-emissivity (or low-E) glass actually restricts heat exchange across the air space between the two panes of glass. This keeps the inner pane of glass warmer thus reducing the instances when condensation can form.In addition, the use of a “Warm-edge” spacer bar made of insulating material will reduce the risk of condensation at the edges.

Outdoor condensation

Condensation forms on the outdoor surface of glass when its temperature drops below the outdoor dew point temperature. Again, windows manufactured with a double-glazing window containing energy efficient low-emissivity glass, have enhanced thermal insulation properties thanks to a high performance transparent coating that reflects heat from radiators or fires back into the room. As a result the outer pane of glass does not get warmed by heat escaping from inside the building through the glass and remains cooler in comparison to less efficient thermal insulation glass.External condensation only occurs in certain climatic conditions with high humidity levels and/or particularly cold weather. It is possible that external condensation will appear on some windows but not on others. This is due to localised atmospheric conditions such as shelter from nearby trees or buildings, variable air currents and wind speeds and varying levels of nearby vegetation.

Condensation on insulating double glazing window

Condensation on the outdoor surface of such high performance windows is in no way an indication of a defective unit. Indeed, this can be seen as a positive indication that the enhanced thermally insulating double glazing window are actively reducing heat loss through the glass.This form of condensation can be counteracted through the use of a hydrophilic coating such as traditional self-cleaning glass. Traditionally a self-cleaning glass attracts water across the surface in a “sheeting” effect allowing clear vision through glass that is susceptible to external condensation.

Defective Units

The formation of condensation on the inner faces of the double glazing window is an indication that the air or gas cavity is no longer completely sealed. The desiccant will rapidly become saturated and any damp air penetrating via the seal around the perimeter will reduce visibility by forming condensation on faces 2 and 3. The double glazing window must therefore be replaced as this cannot be reversed. This double glazing window must be replaced in accordance with the terms and conditions of the warranty.


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    1. Hello Ajay,

      This Blog is not for promotion for any Brand, Company or, Product. Please do not share any link for specific product or, company as otherwise it defeats the purpose of this Blog which is definitely to educate the people about this wonderful product named uPVC Door/Window....i hope that You understand...

  2. I found this blog very detailed and informative clearing all the doubts about UPVC

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  5. Sir, Where can we get acoustic PVB glass? I'm from Chennai and I need to install acoustic PVB glass. Here none is aware of acoustic PVB. Can you please share brand/make of acoustic PVB?

    1. You can get it from Saint Gobain Glass & Asahi Glass.. Please look for their authorized partners in your vicinity..

  6. thanks it was a lot of learning ,reading your blog

  7. PVC Curtains are ideal for controlling temperature and dust between warehouses, cold storage areas, offices etc. Super quality PVC Strips specially designed for Cold Storage Areas.

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  8. Glass doors are the one of the trending doors for the renovated houses and well designed houses.

    Fire proof door dealers in bangalore

  9. Hello, I have browsed most of your posts. This post is probably where I got the most useful information for my research. Thanks for posting, maybe we can see more on this. Are you aware of any other websites on this subject.
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