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How to Clean Limestone Paving Slabs [Restore Just Laid Look]

If you’re lucky enough to have a limestone patio, then you’ll know how beautiful and impressive it can be. However, with all that natural beauty comes the need for constant care and attention, mainly with keeping it looking its best. The cost of installing limestone paving is expensive, so we want it to weather well.

In this blog post, we’ll show you how to clean limestone paving using a few simple steps and some handy sprucing options.

Read on to find out more!

What You Will Need To Clean Limestone Paving

In order to clean effectively, you’ll need to prepare a few things first. Make sure you have a bucket of clean, warm water, non-acidic soap, a spray bottle and a sponge mop to help work the soap into the surface.

For particularly stubborn dirt and stains, you may need to use a stiff brush to clean the slab thoroughly, but always be cautious of scratching the surface of your paving. Most general wear and common stains shouldn’t require too much elbow grease to clean, provided you use the right products.

Using The Right Cleaner

All natural stone paving is different and will require a different cleaning process to avoid damage or discolouration. Acid-based products are particularly harmful to limestone and can result in colour loss or staining if used.

If you’re in doubt about the solution you’re using, we suggest applying a small amount to an inconspicuous area of the stone; use this to test for any discolouration or staining before continuing.

Will soap and water do?

Using warm soapy water as a paving cleaner is both effective and non-damaging to the stone slab. Although it is hard work.

Make sure you’re using non-acidic soap and dilute a small amount with warm water; this solution should remove most dirt and grime from your paving slabs.

You may need to use specialist products for tough stains, black limestone, or discoloured stones, your washing powder patio cleaning won’t cut it, but we’ll cover that later in this guide.

Pressure Washing Limestone patio slabs

Cleaning limestone pavers with a pressure washer can damage the stone’s surface. Unless your paving suffers from serious scratching or stains that cannot be removed by any other method, we don’t recommend using a pressure washer when cleaning the patio. Certainly not as the first option. It may well not be needed.

If your limestone has been treated, high pressure may be less damaging to the stone. However, we still don’t advise pressure washing natural paving unless the other methods mentioned in this guide have been unsuccessful.

Using bleach

Bleach can effectively remove the moss and algae that often build up on the outdoor stone, but you should be careful.

To avoid any loss of colour or damage to the surface of the stone, you should always dilute this chemical heavily with water. Avoid mixing the solution with ammonia, or other chemicals, as the reaction can be toxic.

Apply the mixture to the stone, scrub with a wire brush until the stain has been lifted, and then wash the area down with water.

Using Professional Cleaners

Professional limestone cleaners can be beneficial when cleaning black limestone paving affected by mineral stains from slightly acidic rainfall. This type of rain can soak into the stone and cause white and grey marks to appear due to a chemical reaction that produces mineral salts.

To keep your black limestone paving clean and help retain its original colour, a specialist product may be necessary with a tested formulation, specifically designed for your black limestone patio.

How to Clean Limestone Slabs Like a Pro

1. Remove dirt and debris

You should always remove any loose dirt and other debris to avoid scratching or damaging the stone. Use a soft broom to sweep, and take care to rid the surface of your paving from any loose materials.

Any small stones, grit or sands present on your paving can cause etching and marks that will be hard to cover or remove in the future.

2. Mix the solution in a bucket

Once you’ve prepped the area for cleaning, take a bucket or other large container, and fill it with clean, warm water. Pour a few drops of non-acidic soap into the water and mix the solution until fine foam forms.

Remember to test the mixture first. Behind the bins or shed is always ideal.

3. Apply the mixture

Once you’re satisfied with the solution, transfer your soap and water into a spray bottle and apply the mixture to the paving. Make sure to cover the whole area and work the soap into any cracks or crevices that you may have missed in the initial application.

Use a sponge mop to clean your patio and be sure to cover every slab. For tough spots that require a little more elbow grease, you may need to apply more pressure or use a brush, but be cautious of scratching the stone.

4. Rinse off the area

Next, you’ll need to wash away the soapy residue. Take your hose and rinse off with clean water, check for any remaining stain that may need more attention and reapply your cleaning product if necessary.

Repeat the process until you’re confident with the results and allow your patio to dry before moving on to the next optional step.

5. Allow time for drying before applying sealant

To help keep your patio clean in the future, we recommend applying a sealant. Although this step is unnecessary, it will protect your patio from future staining and other general wear.

Depending on the product used, the seal can also provide a colour restoration to slabs that has been exposed to direct sunlight, such as black limestone that has faded. This is particularly useful for black limestone, but always check that the product is intended for the stone you’re sealing.

To guarantee a strong seal, you must allow your patio to dry for several hours. Cover your patio evenly and take care to treat the joints around each slab, as this is where mineral salt is likely to build up.

Here are our latest Limestone sealer reviews.

Removing Tough Stains

There are several further options for particularly stubborn stains that prove difficult to remove.

If regular cleaning has left your patio stained with soap scum, you can try applying a small amount of baking soda to the area and rubbing it into the slabs using a sponge soaked with warm water. Work the baking soda into the stain in a circular motion and wash the area clean with water.

For black limestone or steel grey slabs marked by mineral stains, we recommend applying a wet commercial poultice that can remove deep-set stains and provide added protection against future discolouration. Apply the poultice to the affected area and leave for 48-72 hours to dry. The substance can then be washed away with water.

FAQ’s for Cleaning Limestone Paving

Does black limestone require special treatment?

Black limestone is particularly susceptible to colour loss and the white and grey marks left by acid rain. We recommend cleaning black limestone with non-acidic soap.

Can you clean limestone pavers with vinegar?

Although vinegar can be a cheap and easy way to clean many surfaces in your home and garden, it should never be used to clean limestone. The acidity of vinegar can damage your paving and should be avoided when cleaning a limestone patio.

How long should I wait before sealing my patio?

If you’re sealing your patio after cleaning or wet weather, wait at least 24 hours for the patio to completely dry. Any moisture that’s soaked can affect the quality of the seal, so it’s worth waiting to avoid a wasted job.

Last Word 

With these tips and tricks, you’ll be able to clean your limestone patio slabs with ease. We hope that this article has helped introduce some new ideas on keeping your patio looking great and we hope the next time you need a good cleaning for any outdoor surface, you revisit us!