A step by step GUIDE

How to clean your patio slabs

Ensure your patio stands the test of time by following this handy cleaning guide. With hust a little TLC, your paving slabs will be looking as good as the day they were laid. 

We've pulled together our top tips for general maintenance, particular problems and common complaints so you can learn how to clean your patio slabs according to your needs.

Explore our blog for further inspiration and advice on how you can help your garden shine.

Tools you need

Having the right tools and materials before you start mixing cement for your patio will simplify the whole process. Here we recommend making mortar by using a mixer to speed up the job. You can still make mortar by hand however it’ll be a more arduous process. The things you will need to mix your mortar are:

  • Cement
  • Sharp sand
  • Water
  • Wheelbarrow
  • Shovel
  • Buckets for measuring ratios
  • Protective clothing such as work gloves
  • Powered mixer

Cement can be corrosive, so wearing protective gear whilst cement mixing is essential. Before starting the project we recommend discussing the materials with your builder's merchant or installer. 

Best practices for cleaning a patio

STEP 1 Periodic cleaning


When done little and often, washing and brushing should be enough to keep your patio pristine: 

  • Regularly: Sweep with a stiff broom and water.
  • Quarterly: Check for loose or damaged paving stones and ensure all jointing material is intact. Look for stains that need special attention like barbecue fat and bird droppings.
  • Occasionally: Clean your patio or driveway using a suitable patio wash. This can enhance its appearance, but may affect long-term durability so should be used sparingly (two or three times during the lifetime of the paving). Consult our team for cleaning product tips.

STEP 2 Specialist cleaning


Are you trying to tackle a specific problem? Find the correct cleaning solution for your patio slabs below:

  • Algae and fungal growth:
    Apply a proprietary fungicide according to the manufacturer’s instructions.
  • Beverage spills:
    Scrub with hot soapy water and a stiff bristle brush then rinse thoroughly with clean water.
  • Chewing gum:
    For the best results, freeze the area with an ice cube before scraping off the gum.
  • Fresh oil stains:
    Soak up oil with an absorbent cloth or paper towels – don't wipe! Cover the affected area with a dry absorbent powder and leave for 24 hours. Repeat until the powder has absorbed all or as much of the oil as possible. A proprietary cleaner may be needed for persistent stains: apply according to the manufacturer's instructions.
  • Paint, woodstain and varnish:
  • Wet stains: Soak up the spillage with an absorbent cloth or paper towels – don't wipe! Afterwards, immediately scrub the stained area. For paint, use scouring powder and water. Woodstain/varnish should be scrubbed with detergent and water. Paint removers or solvents should not be used on stains less than a week old as this will increase penetration into the concrete.
  • Dried stains: Scrape off as far as possible. Apply an appropriate proprietary paint remover, preferably a thick gel. Follow the manufacturer's instructions or contact the paint manufacturer.

STEP 3 Patio maintenance

Reduce how often you have to clean your patio by taking steps to protect the paving: 

  • Sealing your paving: Make your patio more water-resistant with a sealant suitable for sealing paving. This will make it harder for algae, lichens and weeds to grow and will protect against sun damage. Having sealant on the surface also means easier cleaning and a matte or gloss finish.


Please note: Applying sealant may affect the colour. Use sealant specific to your paving material e.g. concrete, granite etc. It's not necessary to seal porcelain. Sealants shouldn't be applied until after the paving has been laid for at least six months, except for Smooth Natural Sandstone that should be sealed before being laid. Use quality sealant and apply it according to the manufacturer’s instructions. Remember, once applied it can’t be removed.

  • Weeding: Weed seedlings are generally airborne, so it's almost impossible for them to grow through a subbase and laying course. They tend to take root in small joints, especially block paving. For block paving products, we recommend kiln-dried sand or polymeric resin jointing sand, such as brush-in compound, to fill voids and reduce the moisture that weeds need to grow.
  • If weeds do start to grow, pull them up from the root. Grab or pinch the base of the weed to remove as much as possible, or, if space allows, dig out the roots with a small shovel.
  • Efflorescence: Efflorescence is a natural chemical reaction that can occur in all paving products, most commonly in concrete. It looks like a random pattern of white blooms that vanishes when the patio is wet and returns once the paving dries. Efflorescence has no detrimental effect on the performance of the paving and will generally disappear naturally with time. It is difficult to predict how long it will last, but once efflorescence disappears, it usually doesn't reoccur. You don't need to replace the slabs or take other measures against efflorescence.

Cleaning patio slabs FAQs

Can I use an acid-based cleaner? 

Jointing materials may stain/change colour when directly exposed to acid-based cleaners. We recommend testing on a small discreet area first. Limestone, slate and granite are especially sensitive to cleaners so we don't recommend acid-based products for natural stone slabs.

Can I use a pressure washer to clean my paving? 

We don't recommend the regular use of jet/power washers as this may harm the surface of the product over time.

Can I use salt to de-ice my patio? 

No. During freezing and thawing conditions, the use of salt can affect both the durability and the look of the paving. You should use a plastic shovel or stiff brush to remove snow and ice.

Why do paving stones have darker patches? 

This is due to differential weathering, where the surface of the paving has cured at different rates, causing darker colour variation. 

Generally, this is exaggerated by the presence of efflorescence which, once removed, will reduce the effect of the dark patches. As with efflorescence, the dark patches will gradually disappear with time.

Browse our blog for expert tips on paving maintenance beyond how to clean your patio.

Get in touch with Bradstone

For over 65 years, Bradstone has been supplying homeowners with patio slabs and aftercare advice from cleaning to repair. We're proud to give you guidance that you can trust and quality products that ensure attractive and long-lasting results. 

Wherever you are in your garden renovation project, we can help. Browse our products online or at your nearest stockist and order free samples to compare at home. When you're ready, find an installer through us and get extra peace of mind with the Bradstone Assured Guarantee.

 STEP 5 Add The Rest Of Your Sand

The ingredients used for mortar mixing must be combined to create the adhesive. It’s recommended to add a little water as you go depending on the consistency of the cement you need; ideally, your mortar should be wet enough to pour but not too runny that it loses its shape. 

It’s best to start off small as you can always add more, so gradually add a small amount of water and mix it with the dry materials. Keep adding water until you’ve reached the consistency you are looking for. You’ll be looking to achieve a fairly dry but pliable mixture.

 STEP 6 Apply The Mixture With A Slurry Primer

Once you’ve mixed your cement and sand to reach the right consistency, you can use the mortar mixture to lay your patio! Remember all paving needs an application of slurry primer to the underside of the paving slab prior to laying on your mortar bed. For more advice on laying different kinds of paving stones, take a look at our advice section.

If you want high-quality paving stones to improve your home and landscape your garden, your local Bradstone stockist can help. Please click here to find yours. Alternatively, visit our to order up to three free samples today!

STEP 7 Pointing the joints

Use a pointing trowel to smooth off the mortar that has been squeezed out as well as filling the gaps

STEP 8 Adding coping stones

If you're adding coping stones to the top of the wall, then plan the joints you need to avoid vertical joints coinciding, allowing a 10mm joint gap between each coping stone.
If you're using flat coping stones, ensure there is an overhang both along the long face and the short end.
Then lay following the same steps as the walling blocks.