Independent comparisons. We may earn from shop links. More info

Block paving weed brush: clear the joint, then refill it

Updated: October 2026

A block-paved drive looks clean in spring and green along the joints by midsummer. Those weeds sit in the sand that locks the blocks, and that sand is also the seedbed. A block paving weed brush lifts moss, seedlings and grit, and it drags some of that sand out with them. This page is about the pavement: which head reaches a narrow joint, when kiln-dried sand goes back, and why a permeable drive takes a different fill. The brushes in this set are on the [weed brush comparison](/hub/weed-control/weed-brush). The top pick and the best value there are the same brush, the TDBS 104278, an angled wire head on a wooden handle with a scraper. This page is the pavement, not that ranking. Prices and listings were checked on 16 October 2026. Products Compared did not run a lab test.

A block-paved drive looks clean in spring and green along the joints by midsummer. Those weeds sit in the sand that locks the blocks, and that sand is also the seedbed.

Our top picks

TDBS TDBS angled weed brush

Best overall

TDBS TDBS angled weed brush
8.7/10about £9.99
View offer
Mitclear Mitclear 53 inch weed brush

Alternative

Mitclear Mitclear 53 inch weed brush
8.0/10about £11.89
View offer
Newthinking Newthinking wide wire broom

Alternative

Newthinking Newthinking wide wire broom
6.9/10about £13.99
View offer
On this page
  1. 1.Why the joints go green
  2. 2.Brush shape on block paving
  3. 3.Put the right fill back
  4. 4.When the drive needs more than a brush

Why the joints go green

The joint is a few millimetres of sand, open to dust, blossom and leaves, while the blocks are dense. Seeds land in that sand after rain and grow along the line you see from the window. These sources do not trace the growth to the sub-base. Moss on a shaded path makes the surface slippery, which is why the Royal Horticultural Society says to clear hard surfaces for safety as well as looks. A brush is for moss, seedlings and loose debris. The RHS gives roots to a weeding knife and an angled wire brush to the rest. Bristles skim a weed with a crown. If a taproot will not leave a narrow joint, cut it again rather than expect the wires to extract it. Brushing only the green tops leaves the plant in the sand, so the line is often back within a fortnight. Pavingexpert treats a half-empty joint as a pavement problem, because that sand stops the blocks shifting. A brush that reaches the crack disturbs sand too, so refill in the same afternoon.

Brush shape on block paving

A converging wire or brass head, the V-shaped joint tools in this set, narrows into the crack. A wide broom stays on the block faces. Newthinking’s amazon.co.uk listing describes an 11.4 inch head, which scrubs an open face and rides across a joint a few millimetres wide. The wires miss the sand, and the green line stays. Steel wire can mark softer stone, so try an unseen corner first. Brass is gentler on the face and still pulls sand once you press in. UK reviews say bristles skim weeds with a crown, so use a scraper or knife as well. The TDBS 104278 brings a built-in scraper and a handheld scraper on wood. Mitclear brings three brass V-heads on a four-part pole. A sectional pole that unwinds mid-drive wastes a head that fits. Length, spares and that joint are in the weed brush buying guide. Scraping and brushing both drag sand out, so put the right fill back while the blocks are still locked.
TDBS TDBS angled weed brush

Testsieger

TDBS TDBS angled weed brush
8.7/10about £9.99
View offer

Put the right fill back

On sand-jointed block paving, clearing the weed and refilling are one job. Paving.org says to brush dry kiln-dried sand into dry joints. Damp sand clumps and does not lock the blocks. Wait until the drive is dry, then sweep diagonally so the sand drops into the joint. Expect another pass after a shower settles it. Trade pages disagree on bag coverage, so no single square-metre figure is reliable. In the first weeks, the June 2023 paving factsheet says not to pressure-wash new paving. Pull or scrape weeds, brush sand back once the blocks are dry, and keep a jet moving so it does not mark the faces. A washer is quicker on a whole drive and empties joints faster, so the factsheet says to use one sparingly. A brush is slower and still disturbs sand. Neither tool is the refill. In one UK review, a hosepipe restriction left the washer unused. That is one household under a local restriction. On permeable paving, kiln-dried sand can seal a joint built to drain. Paving.org points to the manufacturer’s clean stone and mentions a 3–6 mm grade. If you cannot tell which system you have, leave the bag closed. A spray will not fill the gap; see weed brush or weed killer.

When the drive needs more than a brush

A brush and the right fill are enough while the blocks sit tight and the edges hold. Call a paving contractor if a block rocks, the edge restraint has failed, or a wide band of mortar has broken out. Half-empty joints can start that shift, and scrubbing a loose block does not rebuild the edge. Ask them too if you cannot tell whether the drive is permeable, because the wrong sand clogs a draining joint. Work at height needs the same handover. A long handle suits a drive you can reach from the ground. Where the blocks are stable and the joints are sand, use a knife on rooted weeds and brush dry kiln-dried sand in once the surface is dry. These points draw on Paving.org, the June 2023 factsheet, Pavingexpert and the Royal Horticultural Society, with amazon.co.uk listings checked on 16 October 2026.

Common questions

Why do weeds grow in the joints and not through the blocks?
The joint is sand, open to dust, leaves and seed, and the blocks are too dense for a plant to break the face. Weeds and moss start there after rain, so you see a green line. These sources do not trace that growth to the sub-base. Refill after you clear a sand-jointed joint, because that sand locks the blocks.
Does a wire brush pull the sand out?
Yes. A wire brush and a scraper both drag jointing sand out of the crack, so the drive can be less stable once it looks clean. The June 2023 paving factsheet says to brush that sand back once the surface is dry. A brush is slower than a washer and still disturbs the joint, so refill on the same visit.
When do I brush kiln-dried sand back in?
On sand-jointed paving, brush dry kiln-dried sand into dry joints and sweep diagonally. Damp sand clumps on top and does not lock the blocks, so wait for a dry surface and expect a second pass. On new paving in the first weeks, scrape weeds instead of pressure-washing, then put sand back when the blocks are dry.
What if the drive is permeable?
Leave ordinary kiln-dried sand in the bag. It can block the drainage a permeable drive is built for. Paving.org points to the manufacturer’s clean stone and mentions a 3–6 mm grade. If you cannot tell which system you have, ask the installer or a paving contractor before you refill.
Is a pressure washer better for a whole drive?
It is faster, and it empties joints more quickly. The June 2023 factsheet says to use a washer sparingly, and not on new paving in the first weeks, because a jet can also mark the blocks. A block paving weed brush is slower and still pulls sand out, so you refill either way. A hosepipe restriction is one household’s limit, not a reason to leave joints empty.
Will weeds come back if I only brush the tops?
They often do. Bristles take moss, seedlings and debris. A rooted weed needs a knife, and the Royal Horticultural Society says to cut again if a taproot will not come out. A half-empty joint is a fresh seedbed, so the green line returns unless you put the right fill back.
When should a paving contractor take over?
Call a contractor if blocks rock, the edge restraint has failed, a wide area of mortar needs repointing, or the work is at height. Call them too if you cannot tell whether the drive is permeable. On a stable sand-jointed drive at ground level, you can do the work with a knife, a joint brush and dry kiln-dried sand.

Related pages

How to use a weed brush

Weed brush

Best patio weed brush for the job in front of you

Weed brush buying guide for the right head and pole

Weed brush or weed killer for joints on a UK patio

Sources

Public UK sources from the research digest, last checked on 16 October 2026. Shelf prices and star lines are the amazon.co.uk figures in the display file. A listed length or weight is a manufacturer claim, not a measurement taken for this page.

  1. RHS: weeds on hard surfaces (retrieved 16 October 2026)
  2. RHS: moss on hard surfaces (retrieved 16 October 2026)
  3. HSE: garden pesticides (retrieved 16 October 2026)
  4. GOV.UK: pesticide approval (retrieved 16 October 2026)
  5. HSE: using the right PPE (retrieved 16 October 2026)
  6. Consumer Rights Act 2015, section 9 (retrieved 16 October 2026)
  7. Paving Factsheet 1 (June 2023) (retrieved 16 October 2026)
  8. Paving.org: kiln-dried sand (retrieved 16 October 2026)