Window Tinting in Knoxville, TN

Tennessee's window tint law in plain terms

Tint darkness is measured as visible light transmittance, or VLT — the percentage of light that passes through the glass and film together. A lower number is darker. Tennessee's rule, in Tennessee Code Annotated § 55-9-107, is that a vehicle's windows may not have a VLT below 35%. The windshield is stricter: it must stay at 70% or above, apart from the manufacturer's shade band across the top.

The law also puts duties on the installer. A shop that applies film must affix a compliance label to the vehicle and give the owner a signed receipt. A violation is a Class C misdemeanor. If you have a medical condition that requires more protection from sunlight, Tennessee has an exemption process; ask your physician and the Department of Safety how to apply before installing anything darker.

Two practical points. Factory glass is not perfectly clear, so a film labeled 35% on glass that already blocks some light can read below 35% on a meter — a good shop will measure your glass and choose film that keeps the combined reading legal. And this is a summary, not legal advice: for the factory privacy glass on SUVs, trucks and vans, ask your installer how the rule applies to your vehicle.

What the percentages actually look like

The number is the light that gets through, so 20% is darker than 35%, and 5% — often called limo tint — is nearly opaque from outside. At 35%, the legal limit here, you can still make out the shape of people in the car in daylight; the glass looks clearly tinted but not blacked out. At 20%, the interior is hard to see into from outside in daylight, and looking out at night through side windows takes more care, especially when backing up. At 50%, the tint is subtle and the main benefit is heat and glare reduction. At 70%, most people will not notice the film at all.

Darkness and heat rejection are different things. A light ceramic film can block more heat than a dark dyed film, which is why people who want comfort without a dark look choose ceramic in a lighter shade.

• 70% — nearly invisible; chosen for heat and UV rejection
• 50% — light tint; noticeable glare reduction
• 35% — Tennessee's limit for passenger car side and rear windows
• 20% — dark; below the Tennessee limit on a passenger car
• 5% — limo tint; well below the limit

Dyed, carbon or ceramic film

Dyed film is the least expensive. It darkens the glass and cuts glare, but it rejects the least heat and can fade or turn purple with years of sun. Carbon film costs a little more, holds its color and rejects more heat. Ceramic film uses non-metallic ceramic particles to block infrared heat without interfering with phone, GPS or radio signals, and it is the best performer for comfort.

Consumer Reports notes that ceramic tinting usually costs several hundred dollars more than other film types. Whether that is worth it depends on how much time you spend in the car in an East Tennessee summer and how long you plan to keep it. On a vehicle you will own for years, ceramic is the film people least often regret.

What window tinting costs

Kelley Blue Book's guide puts tinting a sedan at roughly $250 to $500, and notes that a large SUV or van done in premium nano-ceramic film, sunroof included, can reach $1,000 or more. Within that range the film type is the biggest factor, followed by the number and shape of the windows — a steeply curved rear glass takes more skill and time than a flat side window.

Removing old film first adds to the bill, as does a windshield strip or a full windshield in a clear heat-rejecting film. Ask for the price to be itemized by film brand and line, and ask what the warranty covers. A lifetime warranty from the film manufacturer against bubbling, peeling and color change is common on better films.

After the install: cure time and care

Film is applied wet, and the moisture between the film and the glass has to evaporate. Most installers ask you to leave the windows up for three to five days, and longer in cool or damp weather. Rolling a window down early can catch the film's top edge and peel it.

A hazy look or small water pockets in the first days is normal and clears as the film dries. Clean tinted glass with a soft cloth and an ammonia-free cleaner; ammonia attacks the film. Tint also appears slightly darker once fully cured than it does on the day of installation.

Removing old or failed tint

Film that has bubbled, turned purple or begun peeling has to come off before new film goes on. Shops soften the adhesive with steam or heat and peel the film, then clean the residue. The rear window is the delicate part: the defroster lines are printed on the inside of the glass and can be damaged by scraping, so it is the place where professional removal is most worth paying for.