Bamboo Flooring: Bright Green or Bamboozled?March 26, 2009
Is bamboo flooring as green as grass, or have consumers been bamboozled by its marketing? That question has no simple answer, because the devil is in the details.
Over the past few years, swayed by durability and sustainability claims, thousands have installed bamboo floors. But a simple internet search turns up complaints like this one:
When my two year old drops a PLASTIC cup on the floor from 2 feet and it leaves a 1/8 inch dent, that’s a soft floor. They’ve done the same on my sister’s oak floor and it doesn’t leave a mark, much less a gouge…
How can experiences like this be reconciled with claims that bamboo is “as hard as oak”?
The answer is that bamboo floors can offer great durability – and even be used on basketball courts – if they are carefully chosen! The thing that makes the difference between fabulous flooring and an underfoot flop is maturity.
While I fully advocate taking the time to investigate the options and make a considered buying decision, I’m speaking here of the maturity of the bamboo, not the buyer. Although bamboo can grow to its full height in six months or less, it can take six years to “lignify” or harden. Flooring that has been made from green bamboo will dent more easily, as will flooring that has been made from the top, rather than the stalk, of the plant. In addition, bamboo flooring that has been darkened by being “carbonized” will be about 20% softer than natural bamboo flooring. Thus, darker colors are probably not a good choice if you have large pets or rambunctious children – an ironic point, since plenty of parents and pet owners have deliberately opted for dark colors to hide the dirt their little dears track in.
How green is bamboo, really?
There’s no doubt that the bamboo plant is fast growing and easily renewable. Some species can grow up to three feet a day! A bamboo plant – which is actually a grass, rather than a tree – matures in less than five years while many hardwood trees take 40 to 50 years to mature. Those facts give bamboo a leg up when it comes to sustainability.
In addition, the bamboo industry makes a positive contribution to humanity; 6 million people in China work with it and 600 million people worldwide rely on income from it.
On the other hand, bamboo generates a large carbon footprint when being shipped halfway around the world to us. Forests are being cleared to grow bamboo, and that creates a monoculture, plus erosion and loss of biodiversity. Although some claim that fertilizers are not necessary, they are being used to increase yield. And while the sustainability practices of hardwood growers are now reliably verified by the Forest Stewardship Council (FSC), there’s little oversight of bamboo plantations in China.
So when it comes to being an environmentally and humanely responsible consumer, it would seem that the best advice I can offer is caveat emptor. In most cases, neither your flooring’s label nor your retailer is going to be able to tell you what part of the plant was used in making the flooring or how old the plant was when harvested – or anything at all about the people who made the flooring. Knowing the names of some reputable manufacturers, some of whom are named at the end of this post, is helpful.
Price is also somewhat of an indicator, and I would avoid the cheapest versions not only for reasons of sustainability and durability, but also for reasons of health. Bamboo flooring factories often use glues that include high levels of formaldehyde. That can cause serious health consequences, particularly those with asthma or severe allegies. (As noted in my post Killing Me Softly with Carpet, one of the reasons people choose hard flooring is to avoid the allergy problems and chemicals associated with most carpeting.)
How Much It Costs
Prices for bamboo flooring start at under $2 per square foot and can go up to more than $8 per square foot (2009 prices), not counting installation. Manufacturers of cheaper versions of bamboo flooring will “economize” by finishing the floor with less durable coatings. That economy is apt to be fleeting because the floor will scratch and marr, and you’ll find yourself wanting to replace it much sooner.
|Horizontal bamboo flooring|
|Vertical bamboo flooring|
More durable bamboo floors are finished with a UV coating or an aluminum oxide finish. If your flooring has been finished with Klumpp lacquer, which is regarded as an industry standard, you will have an extremely durable aluminum oxide finish that is also certified to be very low in dangerous and toxic substances. Frequently, floors with a Klumpp coating will also feature a longer warranty.
Bamboo floors of all stripes are beautiful (and some do have stripes). The way the bamboo is processed creates some different looks, as well as different colorations.
Bamboo flooring can have either a horizontal or vertical grain, as shown in the images at left. The difference in pattern – with or without horizontal knees – reflects how the bamboo slats were laminated. The grain becomes horizontal when the pieces are arranged and laminated side by side. Vertical grain results from the slats being placed upright on edge prior to lamination.
As mentioned above, darker colors are produced by heating the bamboo. This carbonization weakens the floor somewhat, but depending on your lifestyle, that may or may not be a problem. Popular carbonized darker bamboos are comparable to black walnut, considered a soft hardwood, while tests show that lighter, natural colors are comparable to maple.
Striped or mottled coloration results from a manufacturing process in which long strips of bamboo are woven together and then compressed under extreme pressure and heat. This produces flooring that is harder and denser than traditional bamboo flooring.
Engineered Bamboo Flooring
The higher the ply count of a laminate bamboo floor, the more stability it has, which helps to protect against expansion and contraction from moisture. “Engineered” bamboo floors, such as the Plyboo floor pictured at the top of this post, offer greater durability and less expansion than other bamboo flooring. Engineered bamboo, like engineered hardwood, is the real thing, and it doesn’t look any different. It’s simply layered so that the plant’s grain alternates 90 degrees from layer to layer. This limits the amount the bamboo swells and contracts in response to changes in moisture. (You can learn more about engineered wood floors in my post The Devil has Zebrawood Floors.)
How It’s Installed
Your installation choices are largely the same as with any hardwood floor: the flooring can be nailed down, stapled, glued or “floated”. A floated floor is secured across its width by interlocking edges on the planks, then secured at the edges by the baseboard.
No matter which method of installation you choose, you will need to take some preparatory steps before installation. These include proper floor preparation, moisture testing and allowing the bamboo to acclimate. The moisture content of bamboo flooring needs to be within 2% to 4% of the moisture content of the subfloor, and it’s a good idea to let the bamboo sit at the site for about a week to make sure it adjusts to that degree.
While a click-together floated floor is relatively easy to install, you will need a contractor’s help to ensure that your subfloor is up to par. Poor preparation is frequently the reason for later problems with bamboo flooring. Your subfloor should be flat while with no more than 3/16 inches in variation over a span of 8 to 10 feet.
It’s also advisable to engage a contractor if your flooring is going to be nailed, stapled or glued. Gluing can be a bit tricky. The manufacturer’s recommendations for adhesive should definitely be followed, and water-based glues should be avoided, no matter who does the installing.
Caring for Bamboo Flooring
It’s best to vacuum or sweep to remove dirt and grit prior to cleaning the flooring. You should use a specially formulated wood cleaner rather than wax, oil soap or other household cleaners. When a spill occurs, soak up the liquid promptly.
You should protect any hardwood, bamboo or cork floor by putting coasters under furniture legs, using area rugs in high traffic areas, and allowing at least eight steps of transition tile or rugs at outside doors. Avoid walking on your bamboo (or linoleum) floor in high heels. A 100-pound woman in a stiletto heel actually exerts more pressure than a barefoot, 6000-pound elephant, which explains why high heels are the number one enemy of wood, bamboo, cork, linoleum and even some forms of tile flooring.
You should also be aware that sun and ultra-violet rays can accelerate the natural oxidation of bamboo. Dark-colored, “caramelized” bamboo products will lighten while uncolored bamboo products will tend to darken over time. To ensure that this natural process doesn’t leave tan lines on your floor, it’s a good idea to periodically rearrange rugs and furniture.
Good Sources of Bamboo Flooring
- Forest Stewardship Council Certified Smith & Fong’s Plyboo bamboo flooring
- Sustainably harvested Madagascar Bamboo products
- Planet Green’s directory of Bamboo Flooring manufacturers
Visit Nicolette’s Comfort and Joy Interior Design website
Rhapsody on a Windy Night
(excerpt – full poem here)
…The lamp said,
Here is the number on the door.
You have the key,
The little lamp spreads a ring on the stair.
The bed is open; the tooth-brush hangs on the wall,
Put your shoes at the door, sleep, prepare for life…”