Learn about Lightfastness with Greenhouse Fabric's Melissa Wolck

What is Lightfastness?

by Greenhouse Fabrics on March 1, 2017

Written by Melissa Wolck

You may have heard the terms “lightfastness” or “colorfastness to light” when shopping for the perfect fabric. Maybe you have seen a lightfastness rating or a particular number of light hours listed on a fabric's specs, but maybe you didn't know what they meant or fully understood their significance. Let’s discuss!

Lightfastness or Colorfastness to light is, “the degree to which a dye resists fading due to constant light exposure.” Although this may be particularly important when shopping for fabric that will be used in a sunroom or outdoors, it is important to note that all dyes have some susceptibility to light damage. Problems with fading tend to occur when the fabric chosen was not produced to meet the end use, like using a basic multipurpose cotton print on patio furniture.


Most fabric manufacturers complete UV tests that provide consumers with a rating that directly correlates with the fabric’s ability to resist fading or it’s lightfastness. The most commonly used method in the United States is the American Standard AATCC 169.3. With this test the fabric is exposed under specific conditions to a controlled light source which simulates the sun spectrum of Albuquerque, New Mexico. At timed intervals, the test swatch is compared visually to a gray scale and the degree of fading is rated on a scale from 1 to 5.

1 = Very Poor, High Degree of Fading

5 = Very Good, No Fading


AATCC 169.3 American Standard Test

Manufacturers may also provide a lightfastness in number of sunlight hours. Any number of hours could be given, but outdoor fabrics usually rate anywhere from 500-2000+. The exact number of hours or years a fabric will last without fading is impossible to determine as there are many factors that come into play, such as the type of dye used, fiber content of the fabric, sun intensity and geographical location.

Let’s take a moment to consider the difference of the sun’s intensity in New York compared to that of New Mexico.

Other factors that may affect lightfastness include temperature, humidity, and airflow.


Global Solar Intensity Potential

Keep in mind that we are affected by the sun’s UV rays all year round and even on overcast days. The sunlight that shines into our rooms in both summer and winter can cause color fading. Line draperies with protective lining, consider the harshness of the sun’s light through your windows, the number of hours of direct sunlight, and whether or not your fabric will be protected by the shade when selecting your fabric.

Genuine Leather: NOT what you think it is

Let's hit pause on reupholstery and refinishing and talk about the big furniture menace of the moment: "bicast leather." While you're all going out and shopping for sofa and lounge chair replacements, you should have this information in your back pocket. If I can keep even ten people from getting conned by new furniture sellers trying to peddle fake leather, I'll have a good day. So read on:

I replace what people call "genuine leather" ALL DAY. EVERYDAY. And I'm not talking about ten year old sofas. I'm talking about furniture people bought from companies less than two years ago that cost thousands of dollars. Bicast leather, or recycled leather, while some are responsibly made, is a farce. It doesn't hold up, and it's costing people lots of money.

Why furniture manufacturers aren't being held accountable? Well, that's easy. The manufacturer punts it to the dealer who then sells it with a limited warranty. Who has to deal with it? The customer who is buying what he/she can afford which is a cheaply made piece of furniture. After all, that same person can't afford to reupholster a sofa he/she just bought less than five years ago. So, it ends up in a landfill years before it had to be there, and guess what bicast leather is made of? Polyurethane. That's right. (that's another rant for another day, though)

Let me tell you something, everyone. If it's real leather, look for two things:

1. A higher price.

2. No cotton or non-leather backing on the material. In other words, it should be leather from front to back.

A cow does not come in 54" wide rolls. It's curvy; therefore, furniture made with real leather hides will always have seams. If you're looking at a piece of furniture, and it has no seams, it IS NOT LEATHER.

How to know if a prospective piece of furniture has real leather or not? Ask the representative helping you for a sample of the fabric. Trust me, you'll know immediately if you're dealing with genuine leather or not. If the representative can't give you a sample, I wouldn't buy it. You need to know what you're getting.

Now, what if you already have bicast leather, and you're concerned it may have started breaking down. Here's some warning signs: peeling, bubbling, or cracking. The top layer, which is usually polyurethane, begins to pull apart from the cotton or recycled leather backing behind it exposing the two layers of the fabric. There's nothing you can do to stop this from happening. It can only be replaced panel by panel. The areas that have the most wear and tear will show these signs first, and maybe they're the only areas that do, maybe not. If I were you, I'd call up the company I bought it from and raise some hell. 

There you have it. The long and short on the fake leather game. 

It needs to be said that there are thousands of faux leathers and vinyls out there marketed responsibly and made to last for a very long time. But, there is a key difference. They are marketed for being exactly what they are and not as something they are not. I am a HUGE fan of faux leather and vinyl, and when they are made responsibly and correctly, they are an excellent choice for furniture. However, any material both manufactured to deteriorate and marketed in a deceitful manner is being sold outside of an acceptable commercial ethos.