Project Fact Sheet
WHAT IS POWERWASHING?
A high-pressure stream of water is passed through a wand that is moved slowly and carefully, back and forth along the grain, over exposed wooden surfaces to be cleaned.
The powerwasher pump converts garden hose pressure of
40 psi (pounds per square inch) to as high as 3000 psi. Pressure is adjusted
during cleaning as appropriate to the wood’s type, age and condition.
DOES POWERWASHING REMOVE SEALANT OR DECK STAIN
REMAINING FROM PREVIOUS APPLICATIONS?
Sometimes, but often not. In these cases, the surface can be sanded or a
SEALANT REMOVER can be applied. The surface is “painted” with the liquid,
allowed to work for fifteen minutes, then hand-scrubbed with deck brushes
and rinsed with a garden hose or powerwasher to remove all traces of sealant.
This process is also recommended for sensitive wood surfaces, like cedar,
that could be very easily damaged by high-pressure water.
In these cases, the sealant removal is followed by the application of a BRIGHTENER
to neutralize the chemical effects of the sealant remover on the wood.
Several rinses, and often a light powerwashing, must be applied
to complete the neutralization process.
These chemical processes can be very messy and VERY HARMFUL TO PLANTS.
All care must be taken by the owner beforehand to prevent the rinse overflow
from falling onto surrounding plant life or pouring into the soil.
This should be a serious consideration for the garden owner
contemplating the degree of perfection to be achieved in preparing
the surface area of a deck, pergola or latticework.
WHAT OTHER WORK MUST BE PERFORMED PRIOR TO PROJECT ONSET?
Temporary access to a water source and to all areas in which
the work is to be performed must be provided prior to the work’s commencement.
Where building and apartment keys are required, a duplicate entry key
must be made available to the crew manager to be returned upon completion
of the project or someone must remain on the premises
throughout the duration of the project to guarantee access on a timely basis.
Ladders will NOT be used by crew members to gain access to locked areas.
Furniture, potted plants and personal belongings must be removed from
all work areas prior to the crew’s arrival. Added costs are incurred when crew members must relocate these items. Stationary items, such as built-in planters, statuary or cooking surfaces and grills may be left in place.
SURFACE AREAS BENEATH ITEMS REMAINING ON THE WORK AREA
WILL NOT BE CLEANED OR SEALED.
WHAT HAPPENS WHEN THE CREW ARRIVES?
Plants and/or areas that ought to be protected from the water stream (or chemicals,
when using brighteners or sealant remover) are relocated, if possible, or covered in plastic. Plants near
the surface to be prepared are covered with plastic fencing and pulled back and away from the surface area when possible.
High-pressure hoses are brought to the highest level of the building to be cleaned,
then lowered to ground level and connected securely to the powerwasher.
Garden hoses from the water source are then connected to the powerwasher
as well, the water is turned on and the VERY NOISY powerwashing machine
engine is started. Several powerwashers are often used concurrently
on large projects to minimize completion time.
NOTIFY TENANTS IN ADVANCE THAT HIGH-NOISE-LEVEL WORK IS SCHEDULED
WHAT WILL IT LOOK LIKE WHEN THE POWERWASHING IS DONE?
There is ALWAYS a brightened color change, because a thick layer
of the dark, dingy color of bacterial damage, sun damage,
greying and seasonal stresses is removed with the high-pressure water.
The exact degree of lightening to be expected is dependent upon
the wood type, the age and the condition of the wood.
HOW DO SEALANTS DIFFER?
There are innumerable sealant types available,
most of which do an effective job of sealing and protecting wooden surfaces.
As a general rule, oil-based
sealants can last one to two years longer
than water-based sealants (acrylics), but acrylics are more environmentally
friendly and require a much easier clean up.
Oil-based sealants soak into the surface and slowly wear away, requiring no removal process between applications. The thinner the oil particles (low viscosity), the more deeply they can penetrate, so lowest viscosity sealants that penetrate deeper
and last longer are always more expensive.
Acrylic sealants form a layer on top of the surface instead of soaking in, which often wears unevenly and requires occasional touch-ups. Acrylic sealant remaining from previous applications must be removed prior to resealing the surfaces, which, over time,
significantly reduces the life-span of the wood.
The EPA has ordered that, as of July 1st, 2009, lower VOC (Volatile Organic Compound) limits will be in effect within the state of Illinois. Under these regulations, oil-based products (which have naturally higher VOC levels than acrylics) can no longer be applied or sold in Illinois unless reformulated to meet these new standards. Contractors may still complete ongoing jobs with oil-based products manufactured prior to July 1st, 2009, but can include only VOC-compliant products in new bids or contracts.
WHICH TYPE OF SEALANT SHOULD WE USE?
Manufacturers of oil-based products are continually reformulating their products,
in order to conform to the new standards. Some have developed
alternative formulas containing alkyds, an EPA-friendly combination
of oil and acrylic, to substitute for the oil-based products currently on store shelves. Others are experimenting with nanotechnology in oil-based products, and
modified acrylic formulas that have oil-like characteristics, yet are, essentially, acrylic.
Because of the ongoing product reformulations addressed above,
new and better products are being introduced to the sealant marketplace every season. It is important to research all new offerings before making
your next sealant choice. The sealant that was the best to use on your deck
last year, may not be the best to use next year.
Within both oil and water-based categories, there are clear sealants that allow natural greying to occur, UV Sunblock sealants that are slightly tinted but highlight the grain for a natural appearance, and semi-transparent and opaque sealants that cover the grain with color, the first partially and the latter completely.
Expensive woods like cedar, Western redwood, or exotic varieties like Ipe, or the Brazilian hardwoods, are usually covered in a sealant that allows the natural beauty of the wood to show, while chemically treated wood and older, damaged wood is typically covered with a product that will effectively mask the stains.
Most brands offer a broad range of colors from which to choose.
WHICH BRANDS OF SEALANT DO YOU RECOMMEND?
We do NOT recommend using any sealant that is not a name brand.
While some deck cleaning companies have developed their own ‘signature’ brands to cut costs, these homemade varieties are often cheaply made and rarely perform as promised. To get an accurate reading of these kinds of sealants’ performance
over time, it is wise to request references from jobs completed
at least two to three years prior to your project’s start date.
There are many excellent name brand sealant formulations from which to choose.
At the pricy end are products made by Sikkens, Messmer’s or Cabot,
which offer extraordinary depth of color and a lasting sheen, but only
modest durability and a complicated, more costly application process.
At the high end, but slightly more affordable, are Sherwin Williams’ Deckscapes acrylics. They can be blended to match any color, provide excellent coverage
and offer long-lasting protection.
Olympic and Rymar products are more modestly priced.
Olympic offers an oil-based, tinted sealant, warrantied to last
at least three years, that is available in virtually any shade.
Rymar’s Xtreme Weather formula lasts up to two years, but emits a very strong chemical odor for several days following application and the color selection is limited.
Both are very popular among condo owners needing to cover multi-story porches.
HOW LONG DOES THE SEALANT LAST?
Clear sealants, whether oil-based or water-based, last one year or less on horizontal surfaces and two to three years on vertical surfaces, depending upon exposure.
The darker the tint, the more pigment it has, so the longer the sealant will last.
Semi-transparent sealants can last up to five years, and solid (opaque) sealants last even longer. Water-based sealants can last up to three years, but require annual touch-ups. Many owners of cedar, Brazilian cherry and redwood decks use a clear sealant, to allow the natural beauty of the wood to show through.
Messmer’s is the product of choice in this category, specially developed for use on hardwoods. Every spring, the decks are powerwashed and resealed,
and every three or four years, the vertical surfaces are done.
Owners of pressure-treated wood decks (like most three-story porches),
want to minimize maintenance while enhancing appearance.
They use a tinted sealant with a three-year warranty, like Olympic’s Maximum line of sealants. These decks need to be powerwashed and resealed every three to four years,
and every five or six years the vertical surfaces are done.
HOW IS THE SEALANT APPLIED?
Only the exposed surfaces of the wood are sealed, unless otherwise
agreed upon, and must be COMPLETELY DRY,
usually 24-48 hours after powerwashing or last rainfall.
ALL SEALANT IS APPLIED WITH BRUSHES AND ROLLERS!
While spraying is the easiest way to apply sealant, Chicago winds make it
virtually impossible to spray sealant without getting overspray onto windows and walls. These airborne particles reach areas even blocks away and can destroy
the finish on nearby parked cars, coat children’s toys and expensive grills
in nearby yards or ruin the paint on siding and garages, costing thousands of dollars to repaint. The time saved by using a sprayer is not worth the risk of costly repairs
or lawsuits from disgruntled neighbors.
Our crews take all possible care to protect the property and its surrounding area.
All areas to be protected are tarped extensively and all plants are
lightly watered with a garden hose before they are tarped.
HOW DO I KNOW WHEN IT IS TIME TO RESEAL MY DECK?
While the sealant’s color will fade naturally in the months following your last application,
this is a natural process and does not mean that the surface is no longer protected.
If you fill a glass with water and spill it onto your deck,
the water should form tiny beads on the surface if your sealant is still working.
If your deck is grey and water no longer beads up on the surface … it is time to call
to clean and reseal all your wooden surfaces!