DEAR
TIM: A wood floor is in our immediate future. My husband
and I have been debating the different types and I am very interested
in bamboo flooring. But my husband thinks it is junk. What is the scoop
on bamboo? Is it a good flooring material? What are its good and bad
points? Is it just a fad? Does it require special care after it is
installed? Monica R., Allentown,
PA
DEAR MONICA: Bamboo
floors are not junk and I don't believe bamboo is a fad. They are a
superb building material that is quite possibly one of the most
ecologically-friendly products I can think of. When you hold a piece of
bamboo flooring in your hand, you would swear it comes from a tree as
its weight and density are just like wood. But in fact, bamboo is a
grass that grows up to 40 feet tall in just 4 years. Harvested by hand
in many managed bamboo forests, the extensive root system creates new
bamboo shoots in very short order. No replanting is
necessary.
The bamboo plant is much like a straw as it is
hollow in the center. Mature plants have a wall thickness of up to one
inch and the stalks taper as they get taller. The stalks are milled and
flat strips are cut from the thick plant walls. These strips are boiled
in a solution of lime and boric acid which drives out the starch in the
plant that attracts wood-destroying insects. Once dry, these non-toxic
chemicals are fantastic termite repellents and they also are toxic to a
wide variety of wood fungi that cause wood
rot.
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| You can see that the bamboo flooring is just like traditional wood flooring. But the grain is not as heavy. You can get medium brown colors as well as light bamboo. |
As you look at different
bamboo flooring, you will discover that you can buy it as a solid
material or an engineered product. Engineered simply means the bamboo
is combined with other wood or cellulose products to make a precision
finished material.
Solid bamboo can come as either a
flat product made of horizontal strips or a sleek vertical product that
has many thin strips glued together that stand on edge. The vertical
bamboo makes for an extremely distinctive floor once installed. The
engineered bamboo flooring combines bamboo as the finished wear layer
and either plywood or oriented strand board as the core.
You can purchase bamboo flooring as a raw or
finished product from the factory. The prefinished bamboo flooring is
ready to install. This prefinished flooring can have up to 10 layers of
crystal-clear finish that has a scratch-resistant topcoat. Raw bamboo
flooring can be sanded in the field, stained and finished like
traditional hardwood flooring. It doesn't require any special
care.
Bamboo is installed in the same fashion as
traditional wood floors and modern laminate flooring. It can be nailed
or glued to a subfloor or it can be installed as a floating floor
system where each piece interlocks with another and the individual
pieces create a giant slab of flooring that floats on top of the
subfloor.
The subfloor beneath bamboo
needs to be structurally sound, clean and free of all debris and it
needs to be in the same plane. It would be ideal if the subfloor were
level, but if not, there can't be more than a 3/16ths inch difference
in elevation in a ten-foot radius.
Wood subfloor
systems as well as concrete need to be very dry. Wood should have a
moisture content no higher than 12 percent. Concrete needs to cure
thoroughly and a vapor retarder needs to be in place under the concrete
slab to stop moisture movement from the soil into the bamboo. Crawl
spaces below wood floor systems must also have a high-quality vapor
retarder in place over the soil.
Squeaks between the
bamboo flooring and the subfloor can be minimized or eliminated if
15-pound asphalt felt paper is installed over the subfloor before the
bamboo is installed. Use regular asphalt shingles to fill low spots in
the subfloors in case they do not meet minimum flatness specifications.
The asphalt shingles will not degrade over time as some floor leveling
compounds tend to do.
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| These four samples show both color and grain patterns. The light piece on the right is vertical grain that wears like iron. PHOTO BY: Tim Carter |
It is
possible to make mistakes when installing bamboo flooring. Perhaps the
biggest mistake is to ignore the mandatory acclimatization requirement.
Since bamboo is a hygroscopic material that expands and contracts with
changes in moisture content, it needs to become equalized with the
moisture content of the room where it will be installed. This means the
flooring must be brought into the space where it will be installed and
allowed to sit for a minimum of three days. Often you must open the
boxes and spread out the material so the bamboo flooring can get
comfortable.
Be sure to check the moisture content of
wood subfloors and slabs before you start the installation. Follow the
manufacturers recommendations to the letter. Delay installation until
you meet the minimum moisture requirements.