Pressure washing your home

What to know before you buy

Proper maintenance of the exterior of your home will add value and years. However, most people never think about pressure washing until that nasty black mildew has already formed on your gutters and siding. In this article, we discuss the four major areas of your home (Home, Gutters, Driveway, and Decks) that can benefit from pressure washing and some things you need to know as you decide what to wash and whether to do it yourself or contract the work out to a professional.

Houses

The home is the most common thing that people think about when someone mentions "pressure washing". That's because trim and siding is where mildew develops the quickest, and is the most visible from the street. Even "maintenance free" exteriors like vinyl siding will develop unsightly mildew and algae every year or two. It is important that you remove mildew and algae every 2-3 years as they cause damage to your siding if allowed to grow.

I'm often asked if pressure washing a home is something the homeowner can do for themselves. Unfortunately, there is simple yes or no answer. With the right equipment washing your own house is something possible. However, if you choose to attempt pressure washing your own home, you should do so with great care. Bleach, soap, water, and ladders are a slippery combination and create a serious slip and fall hazard. However, a broken bone or two is not the most serious risk associated with residential pressure washing. A much more serious risk is the possibility of chemical burns to your lungs and eyes. This is hazard is created when the degreasers and chlorine bleach (required to properly clean your home) are atomized by a pressure washer into a fine airborne vapor. These corrosive vapors can then be inhaled or drift into the eyes where they will quickly cause severe damage to soft tissue. Although these injuries are not often fatal, every year many homeowners are hospitalized as a result of chemical burns to the eyes and lungs. If you will be pressure washing your own home, carefully read the labels on the chemicals you choose and select a quality respirator with cartridges designed for the types of chemicals you will be using.

The risks associated with pressure washing chemicals may lead you to believe that you should clean your home using only water. While that may be better for your health, it's not in the best interest of your home. In the absence of proper cleaning compounds one must resort to very high pressures to blast away the dirt and mildew. 2500+ pounds of pressure can easily scar wood, stucco, and concrete, tear siding off the house. Even if you don't damage the siding, high-pressure water can easily pass through gaps in the siding, bypass window seals, and follow ventilation openings and cause serious water damage to the interior of your home. When it comes to exterior cleaning, use the proper chemicals and dial the pressure down. You'll reduce the risk of damage, and be much happier with the final results.

If you elect to hire a professional, these issues will not be a concern for you. A qualified pressure cleaning professional will use a special mixture of chemicals and high tech equipment to clean your home at low pressures without water intrusion or damage to your plants. When interviewing house-washing professionals, be sure to ask them what chemicals and pressures they will use on the various parts of your home. If they are hesitant to discuss their chemicals, equipment, or process, you should be wary. A qualified professional will gladly take time to explain how they will clean your home and what cleaning compounds they will use. Also, if you have a unique siding like cedar or an easily damaged siding like masonite, ask them how they will get it clean without causing damage. Always be sure use someone that is licensed, insured, and bonded and don't be afraid to ask them for proof. A qualified cleaning professional will have these documents with them and will gladly provide copies upon request. Be wary of anyone who seems hesitant to produce them or tries to explain that they are unnecessary.

Finally, you will want to get several estimates. A cleaning professional will provide a written estimate detailing each item to be cleaned. A typical two story home should cost about $135-200 and will take 2-4 hours to complete. If you get estimates that are outside this range, you should be scrutinize them carefully. Obviously you do not wish to pay too much to have your home cleaned, but be particularly wary of the low bidders. These low rates are frequently the calling card of a fly-by-night operator. These fly by night operators can offer such outrageously low prices because they do not use expensive chemicals designed to prevent damage to your home and plants, do not carry insurance to protect your home in the event of an accident, and have not been subjected to background investigations. Don't place your home and family at risk just to save $30-40 on a house wash. Hire only qualified cleaning professionals who are licensed, insured, and bonded.

Gutters

Obviously, gutters are part of a house wash. However, they present a special cleaning challenge and are often listed separately on pressure washing estimated. Hence, we will address them separately here. The black “yuck” that forms on your gutters is a combination of two types of dirt. The first and most common is plain old mildew. It is removed by bleach, and will be removed in during the house washing process. There should be no extra charge for mildew removal. The second, and more difficult yuck that forms on your gutters are the black streaks and dull grey haze. Both of these are a type of oil/tar residue that rainwater leaches out of your shingles. There is no way to prevent these black streaks from forming, but you can slow the process down by keeping your gutters clean to minimize the amount of water flows over the outside of your gutters. These black streaks are very difficult to remove, and the chemicals required to remove them are not available to the general public. Fortunately, a regular cleaning by a qualified pressure-washing contractor will remove them quickly. However, if you have ignored your gutters so long they are already achieved a consistent shade of gray be aware that your first cleaning may require tedious and costly hand scrubbing.

Driveways

Over a period of years, your new driveway will fade from a bright white to a dingy blackish color. This darkening is a combination of mildew, auto exhaust, and tire rubber and grime. This built up grime causes no damage to your drive and can be left alone without worry. However, cleaning a driveway has a dramatic effect on the curb appeal of a home and should be seriously considered if your home is up for sale or soon will be. Consumer grade pressure washers will remove this dirt and grime from the driveway, although they do so at a very slow and tedious pace. If you elect to do it yourself, use a 15degree fan tip and plan an entire day for the job. Never attempt to use a rotary or “turbo” nozzle to speed up the process as you will damage your driveways surface severely. A typical professional driveway cleaning costs $75-125 and takes 1-3 hours to complete. A professional cleaning will employ a rotary surface cleaner for a uniform result and a mildecide will be applied to inhibit the re-growth of mildew. If you do it yourself, be aware that without a mildecide you will probably need to re-do the job annually to keep mildew spots at bay.

Decks

Pressure washing wood without causing damage takes skill, experience, and the right tools. The last place to learn how to use a pressure washer is on your wood deck. If you have no experience working with a pressure washer, you can do a great deal of damage quickly. Professional deck washing is not cheap, but if you consider the years it adds to the life of your deck it is a great value. However, if you are the do it yourselfer type who insists on pressure washing your own deck, here's a few things you can do to avoid causing damage.

Don't use chlorine bleach on wood. Chlorine bleach is a popular deck cleaner because it is cheap and it brightens the appearance of the deck quickly and easily. But like most other things that appear too good to be true, it is. Chlorine bleach destroys a part of the wood called lignin that is responsible for holding the wood together. If you have ever pressure washed your deck before and had to deal with rinsing off squishy pulp, that's the lignin that has been eaten away by the bleach. It's also years of deck life down the drain. If you didn't notice the pulp, you may have noticed that your deck was "fuzzy" after it dried. That fuzz is deeper layers of wood fiber that are no longer bound together. Bottom line: Unless you like replacing your deck relatively often, don't use cleaning products that contain chlorine bleach (sodium hypochlorite) on wood. If you're hiring a professional find out what they are using and make sure that they are not using chlorine bleach.

Do spend money on the proper tools. Cleaning wood without causing damage requires a high volume of water (4 gallons/minute or greater) at a relatively low pressure (around 4-500 psi). Most consumer grade pressure washers are limited to about 2 gallons/minute at full pressure and produce less than one half gal/min when dialed down below 1000psi. A good commercial grade pump and proper set of nozzles will provide the water flow to do the job faster, easier, and with much less damage.

Never use a rotary "turbo" nozzle on wood. A turbo nozzle is a takes a very small intense stream of water and rotates it very quickly to create a much wider cleaning area. They are standard equipment on almost all consumer grade pressure washers because these units lack the power to deliver a wide cleaning fan at useful pressures. The problem with turbo nozzles is that although they may give the appearance of a wide fan, they are actually a tiny jet at thousands of pounds of pressure. And that type of intensity can literally tear the outer layers off your deck and/or leave permanent scars in your wood. Turbo nozzles were designed for blasting dried mud off bulldozers and other heavy equipment. Leave them in your toolbox for the next time you need to clean your wheelbarrow and shovels.

Do buy a breathable penetrating oil sealer: Protecting your deck for harmful UV rays will add many years to its life. However, polyurethane, paint, and other coatings that create a film on the woods surface trap moisture in the wood and greatly accelerate deck rot. Select a quality stain/sealer such as those offered by Ready Seal or WoodTux. These products will protect your wood from harmful UV rays while allowing it to cast off excess moisture and preventing premature wood decay.

Pressure washing can be a fast and inexpensive way of improving the looks and value. Whether you do it yourself, or contract it out to a professional, a little bit of knowledge can make the process much easier and less expensive.