Bamboo is an extremely durable material that is often used in construction in an analogous manner to wood. At a glance, certain bamboos look and feel like trees, so it’s not unusual to wonder: is bamboo wood?
Although bamboo is often used in a lot of the same ways as wood, it is actually a type of grass. In fact, bamboo is the fastest-growing plant on earth with over a thousand species! Although not technically wood, we do use bamboo much the same way, from building homes to crafting utensils!
Bamboo has many wood-like characteristics that make it difficult to tell the two apart. In this article, we’ll compare the characteristics of wood and bamboo so that you can understand what makes them similar and what sets them apart. We’ll also dive into all of the possibilities that bamboo presents us with and whether it can replace wood entirely!
What is wood?
Wood is the porous and fibrous structural tissue found in the stems and roots of trees and other woody plants. It’s an abundant organic material and renewable resource that grows continuously (albeit slowly). Structurally, wood is exceptionally strong and naturally resists compression while maintaining flexibility, which is why it’s so widely used in all aspects of our lives.
When you take a cross-section of a tree, you’re not just looking at wood but the bark, wood, and cambium. The bark is the outer shell that protects the tree, the wood primarily conducts nutrients and provides support, and the cambium is responsible for the rings of growth between the sapwood and inner bark.
But what exactly makes wood, wood? Let’s go over a few of its key properties:
- Mechanical strength: wood possesses numerous strength qualities including high tensile strength, ability to resist compression, flexibility, and hardness.
- Electrical resistance: wood is a natural electrical insulator and doesn’t conduct heat well.
- High insulation: wood is energy-efficient because it requires less energy for cooling and heating than steel or plastic, which have low natural insulation.
- Decay resistance: wood is naturally decay-resistant as long as it stays dry.
- VOC emissions: wood emits lower VOCs (volatile organic compounds) than other materials including plastic, steel, and aluminum.
Bamboo vs. wood – What are the similarities and differences?
Now that you know a little bit more about wood, we can compare bamboo and wood to see where their properties overlap and diverge. This is an important step in gaining a better understanding of bamboo and why it’s so often used in many of the same ways as wood.
Structure
Trees grow upward and outward, and the stem increases in diameter with each new year of growth. As a member of the grass family, bamboo grows much differently. Unlike tree stems that are solid all the way through, bamboo culms do not have bark or wood layers. Instead of the sapwood and heartwood found inside a tree trunk, a bamboo culm is hollow.
Additionally, a tree is a single woody stem of one plant, whereas an entire bamboo grove is actually the same plant with many culms growing from the underground rhizomes. Plus, the vascular bundles in the cross-section of bamboo are scattered vertically throughout the stem unlike the cylindrical arrangement in the woody stems of trees.
Composition
Despite the obvious structural differences between bamboo and wood, the two actually have quite similar material compositions. They both have slender, sharp cells forming a heterogeneous cellular material that is composed of a high quantity of cellulose.
Both wood and bamboo have three primary components: microfibrils, hemicelluloses, and lignin. Wood may also contain certain chemical compounds like starch, resins, and oils, while bamboo consists of waxes, resins, and inorganic salts. Bamboo also has higher ash, silica, and alkaline extractives when compared to tree wood.
Growth rings
Trees have growth rings in a cross-section of their stem. Growth rings are an indication of the increment of wood during the growth period. There are two types of growth rings: springwood and summerwood. Springwood growth rings are much wider and lighter in color than summerwood growth rings.
Unlike trees, bamboo plants don’t have growth rings. Not only is bamboo hollow, but it reaches its maximum diameter in a single growing season, so it doesn’t continue to get bigger year after year as a tree does.
Flexibility
Both wood and bamboo are tremendously strong, yet flexible. Due to its hollow nature, bamboo actually has higher flexibility when compared to wood. The hollowness allows bamboo to be bent into different shapes without breaking.
Can bamboo be used as a wood alternative?
Although bamboo is technically a grass and not a tree, it’s a strong, flexible, and incredibly renewable resource that can be used in much the same way as wood. Wood, as you probably know, is used not only in construction but also in the production of products such as chopping boards, flooring, toothbrushes, paper, coffee filters, and more. It turns out that many of these same products can be made from bamboo, too!
How is bamboo turned into wood?
Trees are constantly being cut down to be turned into lumber for use in all aspects of our lives. The process is relatively straightforward. But how does one turn bamboo into something like a wooden plank?
First, bamboo can be harvested in as little as 3 years, whereas hardwood can take as long as 40-60 years to grow before being harvested! Once harvested, the green outer layer of the bamboo is removed and the culm is cut into strips which are then milled and boiled to remove starch and sugar. This step in the process is important in reducing the risk of decay or insect damage.
Finally, bamboo “wood” can be darkened through carbonization or simply kiln-dried to remove all moisture. Bamboo strips can be additionally coated for protection, but at this point, they are basically ready for your construction needs.
Is bamboo a good option for hardwood flooring?
Bamboo flooring is often mistaken for hardwood flooring. In fact, bamboo and hardwood flooring have a very similar feel and look, though as we know bamboo is not technically hardwood. There are subtle features that make bamboo flooring much different from hardwood flooring.
First, bamboo flooring is actually harder than most hardwood options. It’s also usually much cheaper. However, hardwood flooring can last as long as 75-100 years with proper care, while bamboo floors usually have a lifespan of about 10-25 years.
Because there are a number of hardwood trees with varying properties, there are more hardwood flooring options with different tints and grades than there are bamboo flooring options. That said, bamboo is an excellent choice for hardwood flooring at a low cost.
Why use bamboo instead of wood?
In recent years, bamboo has increasingly been used as a more sustainable substitute for wood. Not only does it grow quickly and easily, but it’s lightweight and incredibly versatile. It has all of the benefits of growing like a weed, as well as the benefits of being as strong as wood.
Although hardwood certainly has its own advantages such as resisting mold and decay for many years, it can take a lifetime to grow (literally). Although trees are a renewable resource, they don’t grow fast enough to support a growing population. This is where bamboo can help by supplementing traditional wood or paper products and therefore reducing the speed at which we cut down trees.
Ultimately, bamboo is a beautiful and sustainable option that can be used instead of wood, or in addition to it.
