Are you considering pressure washing your property? It's a great way to clean it up and restore its original shine, but it's important to do it the right way. In this post, we'll teach you the basics of pressure washing so you can get the job done safely and effectively. Keep reading for tips on equipment selection, preparation, and execution!
The Basics of Pressure Washing
Pressure washing is the process of using high-pressure water spray to remove dust, dirt, grime, mildew and even old paint from surfaces such as buildings or vehicles.
Pressure washers use a pump to produce a high-pressure water stream. Water flows through the pump and is forced out through a special pipe known as the lance or wand, which is then forced through a nozzle attached to the end of the lance.
Pressure washers have various nozzles that you can use to control the spray with your wand, which allows you to change how concentrated the spray is. The high-pressure water stream dislodges dirt, grime, or paint from surfaces and then washes it away into a drain or onto the ground.
Pressure Washing Technical Jargon
Before we go any further it's important to familiarise yourself with the following terms.
PSI - Pounds Per Square Inch (Imperial measurement). The amount of force applied per square inch. A 2000 psi pressure washer can apply 2000 pounds of pressure per square inch.
BAR - This is a metric unit of pressure. 1 bar is the equivalent to 14.5038 psi. 2000 psi equates to approximately 137.9 bar.
GPM - Gallons Per Minute (Imperial measurement). This refers to the flow rate of a pump, more specifically, how many gallons of water can be pumped out by a pressure washer within a minute.
LPM - Litres Per Minute (Metric measurement). Again, this refers to the flow rate of a pump, more specifically, how many litres of water can be pumped out by a pressure washer within a minute.
Types of Pressure Washer
Pressure washers are powered by Electricity or Fuel (Gas to our friends across the pond). Both have their pros and cons.
Electric pressure washers
Electric pressure washers are often the first choice for homeowners as they are easy to source, acquire, store and operate.
Cheaper to purchase than a petrol pressure washer.
Often provided with multiple accessories and attachments.
Great for light-duty applications such as carrying out regular maintenance on a property.
Often have a built-in reservoir (tank) or connection for easy application of cleaning detergents.
Perfect for washing cars, bikes and garden furniture.
Electric washers are low maintenance.
Must be relatively close to a power source.
A water supply with adequate water pressure must be available.
Limited range of water pressure (equivalent to low power).
Not very portable as you can only use it in one location.
Models that only facilitate applying the manufacturers cleaning detergents and chemicals, only allows you to use their products.
Petrol pressure washers aka gas-powered washers
When you need your pressure washer to do a lot of work, a petrol-powered (gas-powered) machine is the way forward. As they provide more power than their electric counterparts which means they clean surfaces much more efficiently and get the job done quicker! They can be intimidating especially when using for the first time, but don't worry, with practice your confidence will grow.
In most cases, they have a higher PSI and LPM than electric models and are therefore more powerful.
Great for heavy-duty applications such as cleaning heavily soiled surfaces.
Suitable for commercial use.
Produce consistent, quality results.
Do not require a power source.
Fuel needs to be purchased regularly.
They are noisy when in operation.
Often require additional costly purchases to be fully equipped to carry out tasks.
Require regular maintenance.
Harder to operate.
Require tanks to draw water from.
More expensive than electric pressure washers.
Electric or Fuel Powered Pressure Washer?
Your requirements and budget will be the deciding factors that will dictate the answer to this. If you are looking for a pressure washer to clean your bike, car, garden furniture, or to carry out light maintenance on your house and want something easy to use, you may want to purchase an electric pressure washer.
Fuel-powered pressure washers are used by professional pressure washers for a reason. They are the most powerful type and can tackle virtually any job you throw at them. The downside is that they are often more expensive to buy, but if you want to do a top job and achieve the best results, you'll probably want to purchase a fuel-powered pressure washer.
Pressure Washing Equipment & Accessories
When planning your pressure washing project, consider what type of equipment you'll need to get the job done.
Choosing the correct nozzle to complete a given task is essential. If you choose the wrong one you can cause irreparable damage or fail to achieve desired results.
Nozzles come in a variety of sizes, some are color coded for easy reference (red nozzles, black nozzles etc) and typically correspond to the following:
Red nozzles - Zero-degree tip which provides what is known as a pencil jet and is the one that can cause the most damage.
Yellow nozzles - 15-degree tip - Removes paint and other material.
Green nozzles - 25-degree tip - Removes dirt, grime, and algae.
White nozzles - 40-degree tip - Used for washing down after cleaning.
Black nozzles - 65-degree tip - Typically used for applying detergents.
A variable nozzle allows you to adjust how wide of a fan you wish to use and allows you to switch from a jet spray to a wide fan spray instantly without the need to stop and change the nozzle.
A turbo nozzle is a fantastic bit of kit. When used it's like turning your machinery onto turbo mode. Unlike typical nozzles that differentiate by how wide of fan they produce. A turbo nozzle adds a rotational vortex into the mix which significantly assists with removing dirt from surfaces.
Awesome bit of kit. Allows quick application of chemicals and cleaning detergents. This tool is more used by professionals due to its expense and in-depth knowledge required regarding the use of chemicals.
Flat surface cleaner
A flat surface cleaner is a great tool for cleaning large areas efficiently. It contains 2 to 4 nozzles that rotate during operation which allows cleaning to be conducted significantly quicker than using a lance.
Water brooms are great for removing debris from surfaces post-cleaning. They contain multiple nozzles and provide an efficient and effective method for washing down surfaces due to their ability to shift debris on a surface, which subsequently speeds up the entire process significantly.
Telescopic lances can be extended out and offer greater reach from a single location. They are commonly used for cleaning the sidings of buildings and roofs, as sidings can be cleaned from the ground without the use of ladders or towers and roofs can be cleaned without walking on them. Subsequently, safety for all, is also improved. Again, these are not cheap.
What are the steps to pressure washing?
If you've read this far you may want to know how to clean your driveway, patio or pathway, so we've provided you with a step-by-step guide in the following:
Remove any weeds present - try to remove as much of the root as possible to prevent re-growth.
Sweep the area with a broom - It doesn't have to be immaculate, but it will make cleaning easier and save you time and effort in the end.
Pre-Treat surfaces with a cleaning detergent. (Optional)
Pressure wash surfaces.
Rinse down. If your pressure washer struggles to move the debris (sand, mud, moss etc) use a stiff broom to sweep sludge into piles, remove it with a shovel and continue rinsing down.
Post-treat surfaces - Not completely necessary but post-treating with something like Hypo (Sodium Hypochlorite) has significant benefits.
It enhances the end result.
As it is a biocide it will kill any remaining spores where organic growth was previously present.
If you want to take it to the next level, seal surfaces with an appropriate sealant to prevent staining and make maintenance easier.
Some surfaces are more robust than others. Therefore, a good technique to adopt is overlapping strokes to prevent leaving lines.
Pressure Washing Safety Tips
Ensure correct protective clothing is worn for example Eye and Hearing protection.
Always keep both hands on the lance and ensure you have a secure grip.
Never pull the trigger if the lance is pointing at you or someone else.
Never point the lance at something that could be damaged when the trigger is initially pulled e.g. windows or the bodywork of a vehicle. An incorrectly seated nozzle will be ejected at high velocity and could potentially smash a window or damage the bodywork of a vehicle.
Always follow the manufacturer's instructions.
Always work safely and be mindful of potential hazards.
Do not attempt to clean asbestos, as it is extremely dangerous to your health.
Be careful when cleaning paint as old paint contains lead (pre 1977) and any lead paint chips will have to be disposed of at a waste disposal facility that accepts hazardous waste.
If unsure leave it to the professionals.
Pressure washing is a great way to clean surfaces, whether it be your house, driveway, patio, pathway, car, boat, bike, or garden furniture. It's effective and efficient for tackling tough jobs because they have many features that make them more versatile than traditional methods such as using soapy water and a brush.
Depending on what kind of dirt your object needs cleaning off, combining the power of the pressure from the water, selecting the correct nozzle, and utilising the correct accessories all the dirt will break down, so you can get rid of them without too much trouble!
If the object you are cleaning is suffering from stains, you may want to consider purchasing a power washer. Power washing more effective at removing stains and restoring surfaces to their former glory. If you want to take things even further you can investigate using a steam cleaner as it will also sanitise surfaces as well.
The following covers some of the most frequently asked questions regarding pressure washing.
What should I spray before pressure washing?
If you're using a chemical such as Sodium Hypochlorite you should spray water onto any surface that may be damaged by any overspray and spray them with water after application.
What is the difference between power washing and pressure washing?
Power washing incorporates heat whereas pressure washing only uses cold water. Both use high pressure to clean a surface but cleaning with hot water allows pressures to be reduced as the hot water helps to soften and remove any dirt or grime residing on the surfaces. Surfaces cleaned using hot water and less pressure, benefit from a more delicate clean as well. The use of hot water also provides a more hygienic clean.
What do you spray on concrete before pressure washing?
Before firing up your pressure washer apply a degreaser. This will aid in removing any greasy contaminants from the surface and help to ensure best results are achieved.
Do you sand before pressure washing?
If you are preparing old paint for re-painting such as wood, pressure washing the surface prior to sanding will loosen any paint and make removing it easier. It will also remove any grime which will save you money. Grime clogs up abrasive pads (sanding pads or sand paper), so by removing it prior to sanding you won't use as many, and will save money due to using less of them.
If you pressure wash before sanding, ensure surfaces are left to dry completely as wet timber or paint will also clog up your sanding pads/paper.
Also, be careful not to use too much pressure and don't hold the lance too close to the surface.
What Size Pressure Washer is Best?
The amount of pressure a pressure washer can produce varies with design but, the pressure determines how well it will clean surfaces. The greater the PSI or BAR and the higher the GPM or LPM rate is, the more powerful the pressure washer is, and usually better results can be expected.
If you've concluded that it's all too much for you, live in Kent and would rather leave it to the professionals, your in the right place, get in touch, we'll be happy to take care of your cleaning requirements for you.
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