How often should I clean my block paving driveway?

A thorough clean once a year is the minimum. If you have trees overhanging the driveway, twice a year (spring and autumn) is better. Regular sweeping throughout the year prevents organic build-up between deep cleans.

Can I use a domestic pressure washer on block paving?

Yes — a domestic pressure washer is fine. Use a fan jet or rotary patio cleaner attachment rather than a pencil jet, and hold the lance at roughly 30cm from the surface. Very high-pressure commercial washers can dislodge jointing sand if used directly into joints.

My block paving has gone green and slippery — what should I do?

Green slippery growth is algae and is very common in damp, shaded driveways. Apply a biocidal patio/path cleaner, allow it to work for 15–30 minutes, then pressure wash off. A wet look sealant applied afterwards reduces algae re-establishment.

Is it worth sealing a block paving driveway?

Generally yes — particularly if you park vehicles on it (oil staining risk) or if the blocks are a premium or pale colour. For dark blocks that are easy to clean, sealing is more optional. The key is to only seal a perfectly clean, dry surface.

How to Maintain Block Paving Driveways | Expert Guide

Block paving is one of the most durable driveway surfaces available — but regular maintenance makes the difference between a drive that looks great at 25 years and one that fails at 10. Here's exactly what to do and when.

Why Block Paving Maintenance Matters

A well-maintained block paving driveway will easily last 25–30 years before any major remedial work is needed. Neglected block paving, by contrast, can start failing within 10 years — with weeds destabilising joints, water penetrating the sub-base, and surface blocks becoming loose and dangerous.

The good news is that maintaining block paving is straightforward and inexpensive if you do it regularly. The key tasks are cleaning, weed control, re-jointing, and sealing — and most of them only need to happen once a year or less. Dalys Driveways has been installing and maintaining block paving driveways across Greater Manchester and Cheshire since 1969, so the advice below is based on decades of real-world experience.

Annual Cleaning

The most important routine maintenance task is an annual thorough clean. This removes the organic matter — algae, moss, lichen, leaf debris — that accumulates in the joints and on the block surface over the course of a year.

How to clean block paving properly: 1. Remove any visible weeds by hand or with a path weedkiller (allow 1–2 weeks for the weedkiller to fully work before cleaning) 2. Apply a suitable path and patio cleaner or diluted bleach solution. Leave for 15–20 minutes 3. Pressure wash thoroughly, working in the direction of the joint lines. Use a rotary attachment if available — it cleans more evenly and reduces streaking 4. Allow to dry completely before re-sanding joints

Important: Avoid pressure washing at very high angles directly into the joints, as this can dislodge jointing sand. A 45-degree angle is ideal. Do not use a pencil jet — it damages the block surface.

Weed Control

Weeds are the most common block paving maintenance problem. They establish from airborne seeds that germinate in the organic matter that accumulates in joints. Left unchecked, their roots can dislodge blocks and compromise the stability of the surface.

Preventing weeds: - Apply a granular or liquid path weedkiller in early spring and again in autumn — treating twice yearly is far more effective than once - Choose a path weedkiller containing residual chemistry (e.g. diflufenican) which provides several months of residual protection after application - Avoid glyphosate-only products on block paving — they kill existing weeds but provide no residual protection, and can cause staining

Polymeric jointing sand is the best long-term defence. Unlike kiln-dried sand, it sets hard when activated with water, creating a firm, weed-resistant joint. If your block paving still has kiln-dried sand joints, re-jointing with polymeric sand (see below) is the single most effective step you can take to reduce weed problems.

Re-jointing

Over time, jointing sand washes out and is displaced by traffic, cleaning and weathering. When joints appear open, shallow or have significant weed establishment, it's time to re-joint.

How to re-joint block paving: 1. Remove all existing weeds and thoroughly clean the surface 2. Allow to dry completely (2–3 days of dry weather minimum) 3. Brush polymeric jointing compound across the surface, working it into all joints with a stiff broom. Ensure joints are fully filled to within 5mm of the block top 4. Compact the surface lightly with a vibrating plate (hire from tool hire shops) — this beds the compound into the joints 5. Remove all surplus compound from the block faces with a blower or dry brush 6. Activate by gentle watering with a fine rose. Allow to cure for 24 hours before use

Re-jointing is typically needed every 5–8 years with kiln-dried sand, or every 10–15 years with polymeric compound. Do not re-joint when rain is forecast — polymeric compound can stain blocks if it gets wet before it is fully swept off the surface.

Sealing

Sealing block paving is optional but offers several benefits: protection against oil and fuel staining, enhanced colour (wet look or natural finish sealants available), reduced weed growth, and easier cleaning.

Types of block paving sealant: - Natural finish / matt sealant: Protects the surface while maintaining the original appearance. The most popular choice - Wet look / gloss sealant: Enhances colour and gives a sheen. Very popular for charcoal and dark blocks but can look artificial if overdone - Impregnating sealant: Penetrates the block rather than coating it, offering protection without changing appearance at all

How often to seal: Every 3–5 years is ideal. Always ensure the surface is completely clean and bone dry before applying — any moisture trapped beneath sealant will cause it to turn milky white. Apply on a warm, dry day with no rain forecast for 24 hours.

Dealing With Common Problems

Efflorescence (white staining): White crystalline deposits on new block paving are caused by soluble salts migrating to the surface. This is normal, harmless and typically diminishes naturally within 1–2 years. An efflorescence remover product accelerates clearance. Do not seal over efflorescence — it will trap the salts.

Oil stains: Treat fresh oil spills immediately with a dedicated traffic film remover or driveway degreaser. Older, set-in oil stains are harder to remove — a poultice cleaner left overnight can help. Sealing the driveway prevents oil from penetrating in the first place.

Sunken or rocking blocks: Individual sunken or loose blocks can be lifted and re-laid. This is a DIY-able repair — carefully lever out the block with a bolster chisel, add or remove sand beneath to correct the level, and re-lay and re-sand. If large areas are sinking, the sub-base may be failing and a professional assessment is needed.

Moss and algae: In damp, shaded areas moss and algae establish readily. Apply a biocidal patio cleaner in autumn — this kills moss and algae and provides residual protection through the winter months.