Inspired by a helpful YouTube guide. This walk-through draws on the video "How to clean block paving", which demonstrates a sensible, step-by-step approach to getting paving looking good again without damaging the joints or the block faces.
1. Clear the surface first
Move any plant pots, furniture, or vehicles off the area. Sweep away loose debris - leaves, grit, and dirt - with a stiff brush. Getting this off before you introduce any moisture saves you chasing mud around the surface later.
If there are obvious weeds in the joints, pull them now. A stiff wire brush or a dedicated joint raking tool makes this quicker. You want nothing in the joints that will hold moisture or interfere with cleaning.
2. Apply a patio cleaner or moss and algae treatment
For green staining from moss and algae - the most common problem on UK driveways - apply a proprietary patio and driveway cleaner. Products such as Jarder Spray and Leave or similar concentrate-based treatments are widely available from garden centres and DIY shops.
Read the dilution instructions and apply with a watering can or pump sprayer. Most need to dwell on the surface for 20 to 30 minutes. Do not let it dry out - if it is a hot day, work in smaller sections.
3. Scrub stubborn areas by hand
Once the treatment has had time to work, use a stiff-bristled deck brush or a hand scrubbing brush to work the loosened moss and algae off the block faces. Pay attention to the area immediately around the joints where build-up tends to be heaviest.
Avoid wire brushes directly on the block faces - they can scratch the surface texture, particularly on smoother reconstituted stone blocks.
4. Pressure wash carefully
A pressure washer speeds things up considerably, but it needs to be used sensibly. Keep the lance moving and do not hold it stationary in one spot. Use a fan jet rather than a pencil jet, and keep the pressure moderate - around 1200 to 1500 psi is usually enough.
Angle the lance slightly to one side as you work rather than straight down. This avoids blasting jointing sand directly out of the joints. Work in strips, letting the water carry the loosened debris to the edges.
5. Rinse thoroughly
Once scrubbed and pressure-washed, rinse the entire area thoroughly with clean water. Chemical treatments left on the surface can continue to react and in some cases leave a white residue as they dry.
Allow the paving to dry fully before assessing the result. Wet paving always looks darker and more patchy than it will once dry.
6. Refill the joints and consider a sealant
After cleaning, check whether the jointing sand needs topping up. Pressure washing inevitably removes some, and thin joints let weeds back in. Brush in new kiln-dried sand or a dry mortar mix (see our guide on stopping weeds in block paving) and compact it lightly.
A block paving sealant applied once the surface is dry and clean will protect against future staining and help the blocks repel water rather than absorb it. It is not essential, but it does make future cleaning significantly easier.
When to call a handyman
If the paving is heavily stained with oil, diesel, or paint, specialist degreasers are needed and the application needs care to avoid spreading the stain further. Call Richard if the job has grown beyond a standard clean, or if the surface needs reseating and re-jointing after cleaning.
Need block paving cleaned?
The Sandwich Handyman can tackle driveway and patio cleaning, weeding, reseating, and general garden maintenance across Sandwich and the surrounding area.
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