How To Pressure Wash Your Home’s Sidings
By David P Lee
Whether you are cleaning or preparing your home's exterior for a repainting or refinishing job, pressure washing is an excellent way to get the job done. You can clean sidings and trims that are grimy, dirty and have
powdery residue from paint that is corroding by spraying high velocity water. You can pressure wash your home's sidings with or without cleaning solution mixed in the water. If you are planning on applying a new coat of paint on your sidings , pressure washing will ensure that the new paint will last longer.
When Not to Power Wash - Pressure washing, also referred to as power washing, is not intended for the removal of paint from sidings even though it is capable of doing this if sprayed long enough in one spot. Training the forceful jet of water this way will erode soft wood sidings and dislodge mortar from brickwork.
Sidings made of vinyl, metal, wood and specific masonry types can be cleaned using pressure washing. However, siding that is made of hardboard and stucco should never be power washed. Moisture can damage the hard word and water can easily deface stucco. If your house was painted prior to 1987, be aware that the paint used is likely to contain lead. It is important that you do not power wash the siding coated with lead-based paint. If your house has two or more stories or if it the area to be pressure washed is rather large, it may be a good idea to hand the job over to a professional who can perform the job better and more safely.
Equipment Used for Pressure Washing - There are places where you can rent pressure washers for $50 to $75 per day. Pressure washers come in varying sizes and pressures. They range between 1200 and 3000 psi (pounds per square inch). If your sidings are wood, aluminum and steel, use a pressure washer that is between 1200 and 1500 psi. For unpainted surfaces, a power washer that is between 2500 and 3000 psi will do the
job. If y you want shorter cleaning times, go with a pressure washer that has a stronger jet. It is best that you go for a pressure washer that will let you mix in detergent to the water. When you do pressure wash with detergent, though, use trisodium
phosphate (TSP). Mix a pound of TSP to four gallons of water. You can rinse the sidings with plain water.
Safely Using Pressure Washers - Before you start pressure washing, clear the surface of any mildew. Hold on to the power washer with both hands and never use it while you are on a ladder. If you are pressure washing high areas, use an adjustable extension shaft to elevate you. If you don't have an extension shaft, there are places where you can rent one. If you have not used an extension shaft before, spend time familiarizing yourself with this contraption, learning how to operate it safely. Point the pressure washer's nozzle approximately three feet from the siding. You can either move closer or farther depending on how forceful the spray is. Make sure that the spray impact is just enough that it is able to get rid of the dirt and grime without damaging the siding. You should never be less than one foot from the siding. Because the water is coming out of the pressure washer at a high velocity and force, never point the sprayer at the windows. It is not safe to point the sprayer at someone else, as doing so can cause injury. When pressure washing, wear safety googles. Make sure that while you are operating the pressure washer, you are far from
electrical wiring or devices.
Outlined below is a general procedure for a do-it-yourself pressure wash of your home’s exterior:
1) Protect plants, lamps and other lighting fixtures, and anything breakable around the house with drop cloths, plastic bags and duct tape. Remove obstacles, and temporarily place outdoor furniture away from the edifice.
2. Use a garden hose to connect the pressure washer to the water source. If the power washer comes with a detergent dispenser, put in TSP and water.
3. Pressure wash from the top of the siding and down. Hold the pressure washing wand at 45 degrees, directing the water jet at soffits, overhangs, gutters and downspouts. Use a side-to-side sweeping motion to spray brush the sidings. Make sure that the nozzle is approximately two feet from the surface of the wall. You can move forward or backward to adjust the cleaning action. When pressure washing underneath the horizontal lap joints of the sidings, aim the nozzle slightly downward. When pressure washing the areas around the windows, aim the nozzle slightly away from the window so that water won't seep into the frame.
4) With a garden hose, rinse the cleaning solution off the sidings with clear water, again working from the top down. If you intend to apply a fresh coat of paint, give the sidings no less than two days to dry up completely.