Pressure washer reviews: FAQs

Patio Cleaner

Patio cleaner attachments often don't clean well between paving slabs

Using a pressure washers is a quick and easy way to get your outdoor space looking fabulous, but getting the best out of your pressure washer can take a bit of know-how.

We've compiled a list of the questions we're often asked to help you choose and use your pressure washer wisely. If you already know how to use a pressure washer safely and effectively, why not visit our list of Best Buy power washers.

How much does a Best Buy pressure washer cost? 

The the cheapest Best Buy pressure washer costs about £75, but is a fairly basic model that is supplied with a lance and nozzle only.

For a Best Buy pressure washer that has a built-in detergent tank (handy when washing cars) or includes a patio cleaner, expect to pay about £200. For more information on potentially useful features and accessories, see the 'features explained' page in our pressure washer review.

Do I need to buy a separate patio cleaning attachment?

Some pressure washers come with a patio cleaner attachment (pictured on the right) but they're often an optional extra, costing around £40-£50. 

Patio cleaners can be useful for large expanses of patio or driveway. They make cleaning easier and less messy, than using a standard jet lance as you're less inclined to stoop when using it and the plastic cover over the nozzle helps to stop dirty water spraying everywhere. They can be particularly useful for cleaning block paving as they're less prone to blasting away the sand. 

Karcher, for example, has a range of patio cleaners - the 'T-racers'. The pricier models have a wider cleaning head so clean quicker, and hand grips so they can be used on vertical surfaces such as fences or walls. Other manufacturers offer their own alternatives - Bosch's Aquasurf, or Nilfisk's Patio Washer Plus. 

However, in our tests, some patio cleaners did not clean between paving slabs very well. Some were uncomfortable to use too because the cleaning head didn't glide over the surface, it juddered, making it difficult to manoeuvre. For a Best Buy pressure washer that has an effective patio cleaner, see our pressure washer reviews.  

Can a pressure washer use water from a water butt?

Some expensive pressure washers can use water from a water butt but most are only designed to use mains water. However, Karcher offer a special suction hose with a filter as an optional extra for many of  their models which enables them to use water from a butt. This costs about £34. For our Best Buy water butts see our water butt review.

Water pouring out the bottom of a pressure washer because of freezing damage

Water is pouring out of the bottom of this Karcher because of freezing damage

Does a pressure washer need to be stored somewhere frost-free?

Yes - in our tests, we've shown that freezing temperatures can cause serious damage to pressure washers. The model shown on the right is now useless. Water is pouring out of the bottom because the internal seals were damaged when we put the machine into a freezer set at -5C for 24 hours without draining it of water. 

Even if you do drain a pressure washer after use (by disconnecting it from your garden hose and then squeezing the nozzle trigger), freezing temperatures can still cause serious damage.

Do you have any tips on how to use a pressure washer?

washing paving

When pressure washing, blast dirt away from you in a sweeping motion

Make sure your hose is firmly attached to the tap and that it has a non-return valve.

If necessary replace worn connectors. All the pressure washers we tested use a standard click-on hose connector and came with a male connector. We found not all were compatible with the female connector on our hose; either they leaked or blasted the hose off. If this happens to you, replace the connector on the hose and/or the machine.

Turn the hose on then release the lance trigger until water runs freely before you switch on the power. Fit the appropriate lance – most have a simple bayonet fitting. The pump will not operate until you squeeze the trigger. Make sure all connectors are tight and there are no leaks.

Work from one edge or corner of the patio, blasting the dirt away from you in a sweeping motion. If necessary use the most powerful setting or the rotary lance to shift ground-in dirt and grime. Rinse off using a lower pressure.

Don't use the most powerful jet setting or the rotary lance when cleaning decking. Hold the nozzle further from the surface or turn the pressure of the jet down. We found a focussed jet could rip up the surface. Test the spray on a non-prominent part of the deck first.

How can I use a pressure washer safely?

Follow these simple safety rules to prevent accidents:


  • Make sure the electrical socket or extension lead you use is protected by an RCD – water and electricity is a potentially dangerous combination.
  • Release pressure before disconnecting attachments.
  • Hold the jet handle firmly and expect kickback when you pull the trigger.
  • Wear safety goggles when using where loose particles could be present.
  • Keep bystanders and pets out of the way.


  • Let children use a power washer.
  • Direct the jet at a person or animal or bring it close to skin.
  • Use any liquid other than water and detergent.
  • Drive over or kink the pressure hose.
  • Use a rotary jet on cars - especially tyres

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