Choosing a window tint shade

What the numbers mean

Tint films are named by their visible light transmission, VLT, as a percentage. A 35% film lets 35% of visible light through the film. A 5% film, often called limo, lets 5% through and is near-black from outside. Because the glass itself already blocks some light, the window ends up a little darker than the film number says. Factory rear privacy glass is usually somewhere around 15% to 25% before any film goes near it.

The front side windows and windscreen have legal minimums (70% and 75% respectively for cars first used after April 1985), which is why the fronts get a separate, very light film or none. Everything in this guide about choosing a shade is about the glass behind the driver, where the law does not set a limit.

Darkness is not heat rejection

This is the fact that surprises people most. How much heat a film keeps out belongs to the film’s construction, not its darkness. A dyed film at 20% VLT looks dark and rejects little heat, because dye absorbs visible light and does nothing about infrared. A ceramic or multi-layer optical film at 70% VLT can look almost clear and reject more total solar energy than that dark dyed film, because it is built to reflect infrared.

So if the reason you want tint is a hot cabin, a baby seat in the back or a black leather interior, start with the film type and then choose the shade you like. If the reason is privacy or looks, start with the shade and then decide how much you care about heat. The films we fit publish their heat-rejection figures, and our tint configurator shows them side by side for each shade, using the manufacturers’ own numbers rather than ours.

One more number worth knowing: UV rejection is close to 99% on every decent film at every shade, including the near-clear ones. Do not pay extra, or go darker, for UV.

Choosing the shade for the rears

• Matching factory privacy glass: if the car already has dark rear glass and you are tinting the doors to match, a 20% or 15% film on the rear doors usually lands close. We hold a sample against the factory glass before cutting.
• Privacy without the limo look: 35% keeps the inside private in daylight, still lets you see out easily at night, and looks factory rather than aftermarket.
• Full privacy: 20% or below. At 5% the rear screen is a mirror from outside in daylight and reversing at night relies on the camera and the door mirrors.
• Estates and SUVs with big rear glass: a shade lighter than you think. A huge dark rear screen darkens the whole cabin.
• Light-coloured interiors: a lighter shade keeps the cabin feeling open; dark tint over a cream interior can look mismatched.

Night driving and other trade-offs

Dark rears are fine at night on a car with good mirrors and a reversing camera. On an older car with a small rear screen and no camera, 5% film makes reversing in an unlit car park genuinely difficult. Try to sit in a car with the shade you want after dark before committing; we can usually arrange that with a sample or a recent job.

Colour matters too. Films come in neutral charcoal, warmer bronze tones and, on some ranges, a faintly blue or green cast. Charcoal suits almost everything. A warm tone can look right on a brown or beige interior and odd against factory grey glass. Ask to see the sample against your glass, not against white paper.

Mistakes we see

• Going darker than the factory glass on the rear doors and leaving the quarter glass alone, so the car has three different shades down its side.
• Choosing 5% for a car that is regularly reversed into a dark driveway with no camera.
• Buying a dyed film because it was cheap and then wondering why the car is still an oven in July.
• Asking for dark fronts. We will not fit them, and any workshop that will is leaving you with a car that can be pulled over and fail its MOT.
• Choosing from a photo on the internet, where the shade depends entirely on the light the picture was taken in.

How we fit it

Film is computer-cut to the exact glass pattern for the car, not trimmed on the window with a blade, so there are no scored edges and no blade marks on the glass. Each window is measured with a VLT meter before and after, the fronts are kept legal, and the figures go on your paperwork. Most tint-only jobs can be priced instantly on the quote form from the registration and the body style; bring the car in if you want to see the shades first.