ᐅ Why do the colors of BILLY shelves change when exposed to sunlight?

Hello everyone, I have a question that has been on my mind for a while: Why do the colors of BILLY shelves change when exposed to sunlight?

I have noticed that the surface or color of my BILLY shelves becomes noticeably lighter or sometimes unevenly faded over time when exposed to direct sunlight.

I am interested in understanding what exactly happens on a material or color level during this process. Is it a chemical reaction in the paint or the laminate? How do UV rays affect the color pigments?

Are there differences between the various BILLY versions, for example, real wood veneers compared to MDF with laminate coating?

I look forward to detailed answers or technical explanations, and any tips on how to prevent this fading would be greatly appreciated. Thank you in advance!

Hello Kekonau,

your question addresses a very important point, as fading or color changes caused by sunlight involve a complex physical-chemical process that should at least be understood on a basic level to prevent damage.

In short, the color changes in BILLY shelves mainly result from UV radiation. These UV rays carry enough energy to break down or alter the chemical bonds in the color pigments and plastic coatings. This can lead to fading or even a shift in color.

More specifically, the surfaces are usually covered with a thin melamine resin film or a layer of paint, which contains color pigments. UV radiation can trigger photochemical degradation here:
1. Pigments react and lose their color intensity.
2. Binders can become brittle, which affects the overall surface.
3. Some color components fade faster than others, causing uneven discoloration.

Interestingly, real wood veneers are more resistant to mechanical wear but can also fade due to UV radiation—especially if there is no UV protective coating.

There are indeed differences between MDF with melamine foil versus painted surfaces: the foil offers some protection but tends to fade when exposed directly to UV light.

For protection, I recommend, for example, not placing the shelf in direct sunlight or installing UV protection films on windows. Special paints with UV stabilizers are also an option if you want to refinish the furniture piece yourself.

I hope this gives you a good technological insight. If you like, I can explain the chemical reactions in more detail. How strong is the sunlight exposure where you are exactly? South-facing, east-facing?

Best regards!

Hey Kekonau and pauPierce,

I find the topic of color fading really interesting – I’ve experienced it myself with my shelves! 🙂

In short: sunlight is basically an invisible "color killer." UV rays act like tiny energy particles that gradually "wash out" the color over time.

You can think of it like a sunburn – except here the color is "burning." But no worries, this doesn’t mean your shelf is damaged; it just doesn’t look as fresh anymore.

And yes, window glass can also affect this: single glazing lets through more UV than double glazing with a UV filter.

My advice: blinds or UV protection films make a big difference, and occasionally moving the furniture, if possible, helps too. 😉

Cheers!

I would like to add some information regarding the materials:

BILLY shelves are mostly made of MDF boards, which are either covered with melamine resin foil or painted. The melamine resin foil contains color pigments that are gradually chemically altered by UV light. The colorants can degrade through photooxidation, meaning that oxygen and light cause a decomposition process.

The key factor is that while the foils are resistant to mechanical damage, they do not offer permanent UV protection. With real wood veneers, the wood color plays a role—here, lignin oxidizes, which can lead to graying or color changes.

Temperature is also important. Sunlight does not only bring UV radiation but also heat. The rising temperature accelerates the photochemical processes.

A protective clear coat with UV filters or positioning the furniture in the shade are the only reasonable countermeasures.

Additionally, IKEA itself states that it is normal for BILLY shelves to slightly fade when exposed to sunlight. This is not a material defect but rather a physical-chemical process.

This is amazing, so much background knowledge about color and sunlight coming together here!! 🙂

I have my BILLY shelves right next to the window and actually noticed that the shade looked different after a few months – a bit duller and lighter.

For me personally, this isn’t a problem, more like a small "patina" of living that somehow makes bookshelves even more interesting 🙂

But if someone cares about perfect color, it definitely makes sense to protect against sunlight with UV protection or to place the shelves in shaded areas.

Thanks to all of you for the information, really great!

Color fading cannot be completely prevented.

Sunlight and UV radiation are the main causes.

Window films with UV protection and shaded areas are the most effective solutions.