Pressure washers are great pieces of kit to have in your home, especially if you have large outdoor areas like patios and concrete driveways.
They can seriously cut down the time that you spend cleaning these areas up and will pretty much always give you a better clean than other more hands-on methods.
There are some items and surfaces that you should never even point a pressure washer at. Really fragile surfaces such as windows can easily be damaged on even some of the lower pressure settings. Often the damage that surfaces are susceptible to is more about water getting under the surface and slowly weakening the object.
So while there are plenty of things that a pressure washer is great for, we’ll be going through a list of things that it’s generally better to avoid with a washer (or if it’s possible to use one, there will be details).
This first one probably goes without saying since mixing water with electricity is pretty much universally a bad idea.
While these meters on the outside of your house will be built in such a way to be waterproof to the elements (thunderstorms, heavy rain), a pressure washer is a much more concentrated stream of water.
This could result in water getting in through the crevices where the panels are fitted and cause some lasting damage.
If you need to clean these, stick to a wipe down!
Air Conditioning Units
It can seem pretty tempting to blast the vent of your AC unit with a jet of water to get rid of all that dust and debris build up, this is not a good idea!
The fins on the unit are actually quite delicate and not as robust as they might look. A forceful stream of water can damage these and bend them out of shape, which will end up restricting the air flow in your AC unit.
A brush (not one with ultra firm bristles though) and vacuum cleaner are your best bet to cleaning these units out without the risk of damage.
Surfaces with Lead Paint
I’ve written in previous articles about using a pressure washer to strip paint from surfaces so that you can clean and repaint them.
This is a great aspect of washers and can mean you can carry out two jobs with one tool.
However, this should never be done on a surface that has been painted using a lead based paint.
Blasting off this paint will mean that there are lead paint particles floating about, which are extremely dangerous to breathe in.
If you really need to get rid of lead paint (which actually is a great idea), then if you’re going to do it yourself, wear some respiratory kit so that you don’t breathe in the paint.
Even better, you can hire a professional to come out and get rid of it for you.
In the same vein as above, maybe you have painted surfaces that you want to clean.
Some places will say to outright never clean a painted surface with a pressure washer because you’ll strip the paint off.
Really, though, if you want to strip paint from something you actually need to be using a pressure washer with a really high pressure output.
You can use a low and/or medium power pressure washer (which is likely the kind you will have in your home) on the lower pressure settings to wash painted surfaces without damaging them.
If the paint has been sealed as well, this will offer some more protection and make it easier to clean.
Wood sidings are prone to build up like mildew and chalking. A pressure washer will certainly wash these away (though mildew will grow back).
However, a pressure washer can cause serious damage if you use it this way.
At sufficiently high pressures, the washer will actually end up forcing water under the outer surface and it will get into the inner workings of your home.
This can damage insulation and electrical wiring, both of which can be a pain and expensive to have fixed.
Water here will also promote mould growth, so if you had a mildew issue before, it will only get worse most likely.
Even aluminium and vinyl siding can be damaged by a higher powered pressure washer, leaving dents and blemishes.
This one is another definite “never”.
A pressure washer is strong enough that the jet of water will strip off the rough granules that give your roof the protection it needs.
Another point to mention here is that using a pressure washer when up in a high place is very dangerous.
Spraying the jet of water can have pretty significant recoil and the knockback can really affect your balance.
If you’re using a pressure washer on a ladder you can be thrown off balance and fall off the ladder.
As with wood siding, the exterior of your house will probably feature some brick work with mortar present.
Again, it can look tempting to spray the wall of your home with the pressure washer for a quick and powerful clean.
With old mortar though, this can be a bad idea and cause a lot more harm than good.
If it is sufficiently old, the jet of water can actually gouge into the mortar, seriously damaging the wall.
Moreover, a high pressure stream of water can cause some material to come loose and this will start flying about, posing a safety risk to anyone nearby.
Bricks themselves are actually brittle enough that a high pressure washer will chip them and lead to debris being lifted into the air.
A regular garden hose is best for this job.
You can wash your car with a pressure washer, provided you use the lowest pressure setting available (this is really important especially for the windows, tyres and lights, which are more fragile than the main body).
A higher pressure setting can start to cause chips and other damage to the paint, which allows rust to start running wild on your car, which quickly becomes very expensive to fix.
This should go without saying, but keep the pressure washer usage to the outside of the car and don’t try and clean under the hood with it!
Finally, the most important (and hopefully obvious) point.
A pressure washer should never be pointed at anything living, be it other people, pets or plants.
The jet of water is nothing to be messed around with as the pressure it produces is high enough to cause injury.
It will look appealing to water your plants while in the middle of your clean, but a lot of plants can’t handle that amount of water that quickly, so a hose or watering can is the best choice.
And there you have it!
Pressure washers are amazing tools when used properly and, with the help of this list, you can wash knowing that you’re less likely to cause damage to anything.
A lot of washers also come with guides on what to wash and not wash so you can also refer to these if you’re unsure.