Privacy glass vs Aftermarket tint

A common misconception with the purchase of a new car is that the “tinted” windows will provide you and your car’s interior from damaging UV rays.


Most car manufacturers install what is known as "privacy glass "... this will not provide you with UV protection or even heat rejection.

 “privacy glass ” will not provide you with UV protection or even heat rejection.

This glass is typically dyed glass and provides only privacy.  Solar glass is a step up from the clear automotive glass and has visible light transmission (VLT) varying from as low as the federal limit of 70% VLT up to 88% VLT (which is clear auto glass). Most automotive solar glass ranges 74-84% these days with UV rejection not much over 40% unless it is factory privacy glass, which has UV rejection as high as the 60 percentile range. Some cars, trucks and sport utility vehicles, in particular, come from the manufacturer with glass that has been darkened using an electrical process called “deep dipping”. This “factory tinted” glass is a dark shade but does not protect the interior of your car from the sun’s heat or damaging UV rays as well as aftermarket window tinting. Major film manufacturers have formulated tinting materials to closely match the factory tinted glass allowing the front door windows of some truck and SUVs have window tint with a legal matching shade. It is also possible to apply aftermarket window tinting over factory tinted glass to make the windows darker and to improve performance.

In other words, “factory tint” means the dye is actually in the glass, it can never be removed. “Aftermarket tint” is a transparent paper with an adhesive side that bonds to the glass, it can be removed.

“When you apply a low visible light transmitted [or VLT] film to an already dark window, such as on an SUV, you’re creating not only the privacy effect, but you’re giving yourself all of the benefits of the thermal barrier for heat rejection and heat absorption, “says Tony Scire of 3M Auto Care Market Center. “It’s very important to understand that eve

n though the glass looks dark coming out of the factory, there are no thermal performance characteristics in the glass.”

Josh Buis of Window Film Operations for Scorpion Window Films agrees that while factory glass may look similar to windows that have aftermarket films installed on them, the performance is rarely up to par with the aftermarket.

“There are many vehicle manufacturers that provide tinted windows from the factory, but this is nothing more than privacy glass and offers to vary little protection from the sun and all of its damaging properties,” he says. “The addition of a light VLT film over your OEM privacy glass will increase the protection on the interior in the rear of your vehicle.”

All of which is to say that when it comes to protection, most OEM window treatments are generally focused only on aesthetics, not performance. That becomes a key selling point for restylers as they educate their customers.

Aftermarket films, however, provide a host of other benefits beyond mere appearance, says Ari Sacal of Solar Gard.

“In North America, 90% of side and rear car windows manufactured today offer very minimal protection from UVA rays,” Sacal says, noting that aftermarket films can block up to 99% of UVA and UVB. “[Aftermarket products shield] passengers against premature aging and skin cancer, and discoloration or fading of leather, vinyl, and fabric … and protect a customer’s investment in their vehicle by protecting passengers and the vehicle interior from UV rays, enhancing passenger comfort and customizing the vehicles aesthetic appearance. This shield protects the passenger’s skin from the sun’s damaging rays, regardless of the film darkness.

“Window films also reject solar energy, decreasing a vehicle’s interior temperature, reducing the need for air conditioning and cutting glare,” he adds.

Block Heat and UV Rays without dark tint

Crystalline line reject 99.9 percent of UV radiation and 90 to 97 percent of infrared radiation.

MOTORTREND Article on Crystalline Automotive Films

A few weeks ago, 3M invited us out for a demonstration of its automotive products. Aside from being an excuse to get of the office, the event offered us an in-depth look at some of 3M’s lesser-known products. While all of the products demonstrated served to enhance a car’s appearance, each had a practical application as well. For example, 3M’s vinyl wraps serve as a removable protective coating for your car’s paint, while also lending it a distinctive look. The Headlight Lens Restoration Continue reading

Protection for your home and your health


To see the damage that untreated glass can do, take a close look at the furnishings in your home.

While it’s understood that taking sun safety precautions is important outside, few people realize they can sustain sun damage indoors, too. While both ultraviolet A (UVA) and ultraviolet B (UVB) radiation from the sun can harm the skin and lead to skin cancers, UVB is effectively blocked by glass. However, at least 50 percent of UVA rays can pass through windows. Window film is an increasingly effective solution, offering substantial indoor protection by blocking up to 99.9 percent of UVA radiation.

Although they are less intense than UVB, UVA rays are 30 to 50 times more prevalent and are present with relatively equal intensity during all daylight hours throughout the year. Window film can help prevent harmful UVA rays from damaging both your skin and your belongings. “To see the damage that untreated glass can do, take a close look at the furnishings in your home that are hit by direct sunlight,” says Perry Robins, MD, President of The Skin Cancer Foundation. “If the sun has faded the color of your sofa, it can just as easily damage your skin when you sit there.”

Available in varied tints, residential and commercial window films can also cut down glare by more than half while allowing 30-80 percent of visible light to get through, depending on the customer’s needs. The benefits of installing window film go beyond protecting one’s skin and household items, as it also can reduce energy costs. In hot weather, window film cuts down heat within the home and in cold weather it reflects interior heat back into the home. Additionally, some new types of “safety” film help hold residential and commercial glass in place if shattered. Several times thicker than the standard sun-protective film, it can greatly reduce the chances of break-ins, property damage, and even personal injury that can result from broken glass.

About 85 percent of melanomas and 90 percent of nonmelanoma skin cancers are associated with exposure to UV radiation. The Skin Cancer Foundation recommends that everyone adopt a complete year-round sun protection regimenthat includes seeking shade, covering up with clothing, wearing a broad-brimmed hat and UV-blocking sunglasses, and using broad spectrum sunscreen every day.

The Skin Cancer Foundation has awarded its Seal of Recommendation to window films manufactured by several different brands, including 3M and Solutia Performance Films. Products granted the Seal of Recommendation have been proven to provide safe and effective UV radiation protection. Use the Seal of Recommendation Product Finder to view products that have earned the Seal.