Full details on maintaining pavers can be found in BS 7533 Part 11:2003 in section 5.

One of the common causes of failure in the public realm is maintenance.

The increased use of street sweepers and pressure washers can remove joints in paving and allow the pavement to move.

As with any paving schemes, maintenance is a key part of longevity. Initial maintenance should see joints being topped up with jointing sand.

During the first 28 days, avoid the use of mechanical sweepers, in particular high suction sweepers, until the joints have become semi-impervious from the sealing effects of detritus.

Surface sealants and sand stabilisers are available, but it is good practice to always refer to manufacturer’s guidelines before application.

General dirt and detritus should be removed with regular brushing.

Clay pavers are generally easier to maintain than other paving products. Here are some examples of specific situations that may occur and how to deal with them.

Moss and algae
This is rarely found on clay pavers unless they are situated in heavily shaded areas. It can be treated with a proprietary cleaner once any thick build up is scraped off.

Oil
Oils do not penetrate easily into clay pavers but it is recommended to remove them promptly with an absorbent material, paper towel, cloth or granules. Wiping is not advised as this will spread the substance over the surface. Steam cleaning can also be used in more demanding circumstances and if this is unsuccessful an emulsifying degreaser should be applied.

Bitumen
When dealing with bitumen it is recommended to wait until it has fully cooled and then scrape it off.

Graffitti and Paint
If the graffitti or paint is still wet when cleaning, soaking it up with absorbent material is advised. Depending on composition, it is possible to treat some paints with white spirit, turpentine or similar solutions and then wash with a degreasing agent. It is highly recommended to be cautious when using this approach and to test on a small area to begin with.

Epoxy or Polyester Stains
These will need burning off with a blowtorch and care must be to taken to ensure the fumes are not in inhaled.

Smoke, Fire, Tabacco or Beverages
Using hot soapy water should remove any residue formed from smoke, fire, tabacco or beverages.

Chewing Gum
This should be addressed by either scraping off or employing a special cleaning provider.

Efflorescence
Clay has a very low soluble salt content so when efflorescence occurs it is usually due to the associated sands. The recommended course of action is to allow the pavers to naturally weather. Chemical cleaners are not advocated.

Lime Staining & Cement Staining
This usually occurs as a result from contamination from an alternative source such as concrete street furniture. The recommended treatment is to pre-soak the effected area and then use a 10% hydrochloric acid concentration.

There are specialist cleaners on the market for various situations. Whatever treatment is used it is always advisable to test a small area first and refer to manufacturers guidelines.