Why the Color of Wood Changes Over Time

2_shelf_rc__37161.1278053963.864.850One thing you may notice about wood is that the color often seems to change. It is important to understand that there is actually nothing wrong with the wood. It is normal for wood to change color over time after it has been dried and it helps to understand what’s going on that causes this to happen. Here’s more information as to why wood can change color:

The Color of Wood Naturally Varies

Wood cells vary in color while the tree is still growing. There are two zones – an inner zone known as heartwood and an outer zone known as sapwood. The cells in the outer zone are newer and tend to be lighter in color. The cells in the center of the tree, known as the heartwood, are darker. The color of heartwood differs depending on the type of tree it is and there are even slight variations in heartwood colors within the same variety.

This phenomenon is, in part, why wood color changes over time. In fact, there is a term known as luster that directly relates to the heartwood. When wood is viewed at certain angles, the color may vary. At some angles it may look dull, at others at may look shiny, and still at other angles the color of the wood may look darker or lighter. This has to do with the original color of the heartwood.

Light Exposure Can Change Wood Color

Another thing that can change the way wood looks over time is whether or not it was exposed to light. The reason for this is that the light itself alters the color of the aging wood cells. The older the wood is and the longer it was exposed to light, the darker the wood will get. This occurs because of a process referred to as photochemical oxidation, which means that exposure to light oxidizes the wood cells and ultimately causes them to change color.

Water Exposure Can Alter Wood’s Color

Have you ever spilled water on wood only to notice later on that the wood changed color slightly? This is why it is so important to make sure that if you do spill water on wood that you wipe it down thoroughly after the spill. Not only can water alter the color, but the minerals contained in the water can further alter the wood as well. For example, iron in the water can darken the wood and maybe even give it a reddish tint.

There are plenty of reasons why wood can change color over time. Color can darken as wood dries, vary depending on exposure to light, and even look different when viewed at certain angles. No matter why the wood changed color, it is all normal and can be dealt with by using different finishes on the wood.