There are companies that have sprung up in the last few
years that advertise “Never seal your deck again”. It
certainly makes for good advertising and certainly grabs
attention, but what does it mean and what does it do for
Sealing your wood protects the wood from moisture, but
sealing out moisture is only a part of what is important
to the long-term health of your wood. Sealing does not
protect the wood from what causes the most damage – the
UV rays from the sun. The only way to protect your wood
from the sun is to stain (not the same as sealing) your
wood. The following describes what each does or doesn’t
Protects the wood from moisture
Sealers are always clear – sealers do not stain the wood
Does not prevent the wood from turning grey
Wood typically starts turning grey in 6 to 8 weeks after
Sealers are not a stain, but stains are always a sealer
Protects the wood from moisture
Protects the wood from the UV rays of the sun
Prevents the wood from turning grey
Allows the wood to be stained with a color of the
For more information, go to
should be used to protect wood?
Exterior wood must be properly maintained to extend the
life of your wood, protect your investment and to
maximize your enjoyment. Paint has been used for
centuries to protect wood. However, paint is effective
only on wood that is vertical. Painting horizontal
surfaces results in peeling within several months.
Horizontal wood surfaces that are stained with a coating
versus a penetrant will have the same discouraging
results. When protecting horizontal wood surfaces, the
only successful option is an oil based penetrating
why: In the sun the top of a deck floor board can be as
much as 50 degrees hotter than the underside of the same
board. When wood is hot and dry it contracts. When
wood is cool and damp it swells. At night or when the
wood is in the shade, the top of the wood will again
expand. Depending where your deck is located on your
home, this process of swelling and shrinking can occur
several times a day. This constant churning will not
allow any coating to adhere to wood for very long. The
only product that will move with the wood is an oil
based penetrating stain. There are many penetrating
stains on the market.
about stains that are supposed to last 4 to 6 years?
To keep your wood healthy,
beautiful and long lasting it is not only important it
be protected from the sun, but it must be kept clean
–much like skin must be kept clean to stay healthy. It
is healthier for wood to be thoroughly cleaned and
stained every 2 and 4 years than to extend it out every
6 to 7 years. Dirt falls down, accumulates and gets
ground into the horizontals surfaces of your wood. This
dirt needs to be removed with a thorough cleaning every
couple years. The vertical portions of your deck will
not accumulate dirt like the horizontal surfaces so the
vertical surfaces need to be thoroughly cleaned and
stained only every 4 years.
Is a rotating surface
cleaning machine good for cleaning wood?
When cleaning horizontal
surfaces, a rotating surface cleaning machine should not
be used. Surface cleaners are designed for concrete
cleaning and should not be used on wood due to wood
being soft. Surface cleaners rotate which means the
wood is being cleaned against the grain nearly 98% of
the time. Cleaning wood should always be done with the
grain to protect the wood.
How do I know when I
should maintain my wood?
A great time to maintain
your deck is before the plants come up and the furniture
comes out. When time is appropriate, as a Roof-to-Deck
customer you will receive a wood maintenance reminder
letter before the season starts which prompts you to
secure an early spring cleaning and staining.
Maintaining your wood will
maximize your enjoyment and protect your investment.
Having the horizontal surfaces cleaned and stained every
2 years and the vertical portions every 4 years with
Roof-to-Deck Restoration is your best value.
by Mike Hilborn, founder of Roof-to-Deck Restoration,
Executive Director and approved wood restoration
educator of the Power Washers of North America (PWNA),
Committee member of the Joint Coatings - Forest Products
Committee. Host of the Roof-to-Deck Home Show.