Carbonized bamboo is a popular type of flooring that is widely misunderstood. The word “carbon” may evoke visions of rock-hard bamboo flooring. And while bamboo does hit the top of the Janka hardness scale, carbonizing has absolutely nothing to do with this quality.
Carbonizing Is About Color, Not Hardness
Yes, the word “carbon” implies hardness and longevity. After all, carbon is the oldest element on Earth. Carbon fiber technology makes for incredibly strong creations, even forming the fuselage for Boeing Dreamliners.
Except for small detail: carbonizing has nothing to do with hardness.
Instead, bamboo is carbonized to give the bamboo a deep, rich, darker color, much like the process of staining wood.
Carbonizing Bamboo Helps It Mimic the Look of Hardwood
Bamboo, in its natural state, has a beautiful light color similar to straw.
While many homeowners desire some properties of bamboo (i.e., it is considered a “green” material, since it is a grass, not a wood), they do not feel that this color is suitable for their home.
So, carbonized bamboo flooring has a darker color that looks more like stained hardwood flooring. And this dark color can be finely tuned to make it darker or lighter.
Steamed, Not Stained
When you stain a hardwood floor, you introduce pigment to the wood’s cellular, porous structure. Wood stain eventually lightens. Foot traffic and especially the sun’s UV rays hasten stain’s color-change.
But carbonizing bamboo is even more internal, changing the very material itself. No pigments are introduced. It is a heat-intensive method (steaming or boiling) that works deeply on the “sugars” within the bamboo.
The process of sugar caramelization is similar. With this, white sugar turns brown under the application of heat. Less heat makes for a lighter, honey-brown color. More heat, dark brown. Even more, heat turns the sugar black—carbon black.
Bamboo Becomes Softer, Less Durable
Bamboo flooring subjected to the carbonization process is about 1/3 softer than regular bamboo.
Carbonization weakens the material, making it softer and more brittle, and it increases the bamboo’s capacity to absorb water, making it less dimensionally stable.
However, the surface is treated with the aluminum oxide finish that is customary for many pre-finished flooring products. Thus, carbonized bamboo can stand up to normal wear.