In most of India the glazing problem is heat, not cold. A glazed elevation that admits daylight while rejecting solar gain saves far more in cooling load than it ever will in heating, which changes what a good specification looks like compared with a temperate climate.
Performance
The three numbers that matter
The proportion of solar energy that ends up inside, counting both what passes straight through and what the glass absorbs and re-radiates. In a cooling-dominated climate this is the figure to drive down, and it is the one most often left out of a quotation.
How much daylight gets through, as a percentage. The design tension is obvious: pushing solar gain down usually pushes daylight down with it. A good solar control product separates the two better than a simple tint does.
The rate of heat flow through the glazing. It matters in air-conditioned buildings because it governs conducted gain through the envelope, and it is the figure a low-emissivity coating and an insulated cavity improve most.
The ratio of light transmission to solar factor. A highly selective coating delivers daylight without the heat, which is what a body tint cannot do — a tint darkens the view in proportion to the heat it removes.
Options
Choosing the product
Colour is through the thickness of the glass, absorbing solar energy rather than reflecting it. Cheap and widely available, but the absorbed heat warms the pane and re-radiates inward, and the thermal stress it creates often makes heat strengthening necessary.
A metallic coating reflects solar energy away before it is absorbed. Effective and long established, though the external appearance is strongly mirrored, which some planning contexts resist and which can cause glare for neighbours.
A microscopically thin coating on the cavity face of an insulated unit that reflects long-wave heat while passing visible light. This is the modern default: it improves the U-value substantially without the mirrored appearance of a reflective coating.
Roughly twice the strength of annealed glass and far less prone to thermal stress cracking, which absorbing tints and partial shading both create. It is not a safety glass, so where fragment behaviour matters it is used laminated rather than alone.
The TPRS product
TPRS Ecosafe
TPRS Ecosafe is a DOWSIL Quality Bond Certified solution from TPRS Glass, offering energy-efficient insulated glass you can count on. TPRS uses high-performance low-E glass to deliver IGUs that cut heat, reduce glare, and help save on electricity. These Insulated Glazing Units not only improve indoor comfort but also come in a wide range of custom options, including Built-in Blinds, Georgian Bars, LED Accents, Curved IGU, Triple Glazed IGU, and Printed IGU, and Laminated IGUs.
Sectors
Where TPRS supplies this
Glass Insights
FAQs
Solar control glass is coated or tinted glass that reduces the amount of solar heat entering a building while still admitting daylight. The best-performing types use a selective coating that reflects infrared energy but passes visible light, so the interior stays bright without the cooling load a clear pane would impose.
Low-emissivity glass carries a microscopically thin metallic coating that reflects long-wave heat radiation while remaining visually clear. Applied to the cavity face of an insulated unit, it is the single most effective way to improve the U-value, and unlike a reflective coating it does not make the building look mirrored.
Not quite. All tinted glass reduces solar gain to some degree, but it does so by absorbing energy, which heats the pane and re-radiates part of that heat inward. Purpose-made solar control glass reflects rather than absorbs, so it removes more heat for a given loss of daylight.
It does not have to. A body tint darkens the view in direct proportion to the heat it removes, but a selective coating separates the two, cutting solar gain substantially while keeping visible light transmission high. Compare the solar factor and the light transmission together rather than either alone.
Because it absorbs solar energy, a tinted pane runs hotter than a clear one, and where part of it is shaded by a reveal, a fin or an internal blind the temperature difference across the pane can crack annealed glass. Heat strengthening raises the thermal stress the glass can take.
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Enquiries
Send the drawing, get a specification
Panel sizes, thickness, make-up and quantity are all TPRS needs to quote. Processing runs from two plants in Puducherry and Dharwad, with offices in Chennai and Bangalore.