Better tools may make a project move along faster or easier, but it is the
quality of the materials that determine the strength and appearance of the
final product. Some projects do not need the strongest, most durable plywood,
but others will fail quickly if the builders make incorrect plywood choices.
Here is how to choose the plywood you need between pressure-treated and
marine-grade plywood.
Pressure-treated plywood is chemically treated to prevent insect damage and
to protect against rot, and it can survive outside without added protection if
exposed only to average amounts of water like an occasional rainstorm or garden
hose. Damage occurs with submersion of the wood in water or its use as an
exterior material in very wet environments.
Manufacturers can apply a water-resistant finish that will reduce the risk
of warping and rot when the plywood is in or on the water. The finish may
extend the life of the material, but it is not a permanent solution. The
problem is the voids in the wood caused by naturally occurring grooves and
holes. Water can enter these voids and cause the wood to rot from the inside.
Another concern with submerging pressure-treated plywood is the risk of
chemicals leaching into the water. In the past, the chemicals used to treat the
wood were arsenic and copper. Arsenic can accumulate in the tissue of fish and
other animals, and high levels of copper are toxic to marine life. Today, many
brands of plywood still use copper, but not arsenic.
However, studies have been unable to produce any conclusive evidence that
the level of the chemicals in the wood is enough to cause serious health risks
to nearby marine life. So it is still legal to use pressuretreated plywood in
docks and other structures in the water in Florida. Although, it is still not
the most efficient material for this purpose.
A better type of use for basic pressure-treated plywood is in yards that are
not overly wet or directly against waterways. Use pressure treated plywood to
build decks, steps, and picnic tables. The wood is also safe for raised-bed
gardens and children's playsets.
Lamination under high heat and pressure and the use of waterproof glue helps
to make marine grade plywood more durable for wet environments. The glue fills
all the voids to keep each layer tight to prevent any warps or rot.
Manufacturers also use hardwood for this product, so it is even more durable.
You can protect the wood even more and make it last much longer by painting
a waterproof sealant painted on a plywood dock, boat, or other immersed object.
The sealant can last much longer on marine plywood than on wood boards that do
not undergo the same lamination process. Another benefit of using marine
plywood is that it can reduce the amount of resealing the structure needs.
Marine-grade plywood does not undergo a chemical treatment to prevent decay
like traditional pressuretreated products. The absence of the chemicals means
it will not deposit hazardous materials into nearby waterways or into the water
when immersed or submerged.
Many people use marine plywood for boats, docks, and other projects on or
near the water or in other wet environments. The plywood can even help to
prevent rot in spas, bathrooms, and other interior areas where dampness is
common. In fact, marine-grade plywood will work effectively for any plywood
project.
Reputable suppliers know the difference between marine-grade plywood and
high grades of traditional pressure-treated plywood. At Mikro Corporation,
our clients can trust the materials we supply for their projects because we
understand the importance of every job. Contact us to learn more about our
product line or to begin your order.
