The Art of Power Washing Decks
Unfortunately, many homeowners have tried using an unlicensed or inexperienced contractor offering a lower price for power washing decks, in some cases this may end up with the job uncompleted or worse. Power washing decks improperly cause thousands of dollars in damage to the surface.
It will cost more time and money to find the right contractor for you but it could cost far more, to hire a company without the proper experience or to do the job yourself. For example, most people don't know that using household bleach to remove the mold and mildew from your deck will actually damage the woods lignin fibers. Or that too much pressure when power washing decks can also damage the woods surface and cause it to splinter or fur. Too many companies have decided they could tackle it without the proper training and with most machines putting out an average of 3,000 PSI it can be dangerous to the operator and your property. Properly learning the techniques and training for power washing decks takes time, training and a long-term investment, each deck or wood surface is different and they all require special attention.
First you have to find out if there is an existing sealer or stain on the deck and how to remove it properly. Very similar to painting, deck sealers and preservatives won't properly adhere to a wood surface that has an existing sealer on it. First this product must be removed from the deck using a stripping agent and you must take steps to ensure that the stripping agent will not harm the plants or siding on the home. Most deck stripping agents have a sodium hydroxide base that will remove the existing sealer or stain and then it can be washed off with a pressure washer using a maximum of 1,000 PSI. When using a pressure washer you must clean with the grain of the wood the entire length of the board. By varying your distance from the wood or not going with the grain you may cause marks and discoloration in the surface. If done carefully, this will leave you with a clean surface for the next step.
Now that you have used a deck stripper to remove the last sealer, the surface must be neutralized so the sealer will absorb and adhere to the wood. Wood and other surfaces can be neutralized using citric or oxalic acid to bring them to a neutral Ph level, Oxalic acid will also remove tannin or leaf stains and also those iron or rust stains from rusting furniture. Now your wood surface is ready to be sealed and there are many other options to consider. The various sealers can be confusing to some but it's important to use a product that has ultraviolet protection from the suns rays. Most sealers have some UV protection, various oils to moisturize the wood and mildew prevention to fight the growth of mildew and mold. The best UV protection can be found in sealers that contain a pigment or stain, almost all of these products form a film on the woods surface, that may wear off with foot traffic or pets, they are semi-transparent allowing the woods natural grain to show while adding a tint of color to the surface. They will also help blend the over all color of the wood if some of your lumber has a different shade than others. You can also use products with solid colors, which don't allow the natural wood grain to show through and in most cases they usually appear to be painted when completed. Then there are preservative-based deck sealers that will penetrate into the wood. These products come in clear and different stain colors and they tend to last the longer because they penetrate into the wood. This allows the oils in the sealer to penetrate into the wood, which keep the wood from dry rotting, cracking, and also blocks the suns UV rays. These preservative sealers will hold up twice as long as the surface film forming agents and they will extend the life of the wood.
Henry Bockman
President, Henry's Housework Inc.
MHIC#65039 Licensed, bonded and insured.
Visit www.Henryshousework.com for more articles and information.
301 216-9675