Mould, dust, dirt and grime are common types of muck among many types of flooring; this includes flagstones. Without cleaning them, the stones can start to look old and tarnished, which can be off-putting to those living in, working in or visiting the property. So, how do you make sure your flagstone flooring stays looking brand new? Well, here you can find out how!

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What are flagstones?

Flagstones are great for areas that need protection from pedestrian traffic. Especially in locations where flat roof waterproofing substrates have been used. They come in a variety of finishes, designs and colours. So, you want to make sure they’re still looking good in years to come.

What is the best way to clean flagstone?

How you clean your flagstones will depend on the type of blemish on your flooring. Nonetheless, cleaning the flagstone flooring is not difficult and can be done with a few simple steps. So, once you’ve figured out what you need to clean up, find your process below!

Preparing your flagstones for cleaning

Hold it! You’re going to need to make sure your flagstone floor is ready to be cleaned. Do so using a soft brush broom or vacuum to gently clean away any dust, sand or grit that has found itself on the floor. Your vacuum mustn’t be in poor condition as the wheels and attachments can damage the surface.

If you have slate flagstones or dark stone flagstones, it’s advised you do not use a vacuum on this surface as damages such as scratches and other abrasions can occur more frequently.

In future, sweeping the flagstones can help reduce the build-up of leaves and debris; further helping prevent stains from appearing on your patio.

Another action you might want to take at this time is removing any weeds from the flooring. Sometimes these can be pulled out (making sure you pull up as much of the root along with it) and other times you might need to use a weed killer if the problem is more widespread.

Now onto the methods for cleaning your flagstones!

General cleaning of flagstones

For grease and dirt, you can use some simple tools to clear this right up!

What you will need

  • Washing-up liquid
  • Bucket
  • Soft scrubbing brush
  • Protective gloves

1. Create a bucket of warm, soapy water.

Add at least two tablespoons of washing-up liquid into a bucket, add warm water and dissolve the soap until it lathers up.

2. Get your gloves on, put the brush in the water and start scrubbing!

Make sure there is enough water and soap on your brush and scrub away at your flagstones until complete. If there are any persistent stains, you can opt for a stone floor cleaner specifically made for this situation.

Cleaning mould from flagstones

If your flooring is in an area that is likely to cause mould (pools or excessive rainy locations), then you might be aware of the dreaded mould infestation! Green and grimy, this is not something you want to stick around.

What you will need

  • White vinegar (other vinegars can stain the surface so make sure you use white vinegar)
  • Soft scrubbing brush
  • Hose or bucket of warm water

1. Use the white vinegar across the flagstones.

Cover the affected flagstones in the white vinegar and leave them to sit for a few minutes. Be careful not to cover any plants; it might not be toxic to them, but it can still cause damage to your little vegetation collection.

2. Rinse the vinegar off the patio and start scrubbing!

Rinse off the vinegar with your hose or bucket of warm water and start to scrub away the mould off the flagstones until complete.

Can I clean flagstones with a pressure washer?

Yes. However, you will need to make sure that the pressure is low when doing so. A high-pressure wash is more likely to cause damage to your flagstones.

What you will need

  • Pressure washer
  • Stone-friendly cleaning detergent (optional)

1. Connect the pressure washer to your mains.

To use your pressure washer, you will need a constant water supply. The mains are your best bet for having the most efficient source of water. So, attach it here as necessary.

2. (If possible) Add a stone-friendly cleaning detergent to your washing.

Some modern pressure washers give you the option to add cleaning agents. If you’re able to do so, spray this onto the affected flagstones and leave for a minimum of five minutes. This will give the chemical time to reach into every nook and cranny.

3. Adjust the pressure slightly and clean, clean, clean!

You can now move your pressure washer across the flagstones. Do so in a consistent manner, using a wide fan and a continuous angle of 45°, to ensure maximum coverage.

4. Detach the pressure washer from the mains and enjoy your newly clean flagstones!

You can now empty the pressure water and be proud knowing you cleaned the flagstone surface with ease.

Can I use bleach on flagstones?

Although effective, it can be damaging to your flagstones and risky to use. Not only can it discolour your stones, but bleach is also toxic to plants. Even if diluted with water.

If you do decide to use bleach, heavily dilute it with water and only use it on specific spots where stubborn mould or mildew are present and rinse thoroughly when done. It’s also advised you avoid using it too regularly because of the issues previously mentioned with doing so. Once a year is recommended if you do want to use bleach as a solution for cleaning your flagstones again.

Some bleaches come with specific manufacturer instructions. Make sure to read these instructions carefully before using the bleach.

Can I use ammonia on flagstones?

Stubborn stains (like algae, mildew or moss) can be cleaned away by mixing ammonia in the water. However, this is an industrial chemical for specific situations, so you mustn’t let it touch your skin. Please view the government guidelines for more information about the uses and exposure risks.

Do you need to replace any or all of your existing flagstones? We’ve got a vibrant selection of flagstones for you to choose from on our site, as well as many more solutions for projects ahead. You can also contact our friendly customer service team for advice on your purchase. Don’t hesitate to get in touch with us for answers to your queries.

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