Why block paving loses its sand when it is cleaned
Conventional sand-jointed block paving is not one solid surface. It is a lot of individual blocks held in place by the fine sand packed into the joints between them. Over the years that sand settles, washes down in heavy rain and drops below the top of the blocks.
Any proper clean removes what is left of it, because the dirt, moss and weed growth you want gone are living in those same joints. So refilling the joints is part of the work, not an upsell afterwards.
What happens on the day
- A look over first — sunken blocks, loose edging, oil marks and drainage are noted.
- Loose debris is cleared and deeper weed growth is dealt with.
- The paving is cleaned evenly, with edges and corners finished by hand where appropriate.
- The surface is rinsed down and left to dry.
- Fresh kiln-dried sand is worked into every joint and the surplus brushed off.
Why it sometimes takes two visits
Kiln-dried sand only flows into a narrow joint if both the sand and the paving are dry. Force it into damp joints and it bridges near the top, leaving the joint hollow underneath. If the paving cannot dry enough on the day, I return on a suitable dry day and complete the re-sanding then, at no extra charge.
What re-sanding does and does not do
Refilled joints lock the blocks back together and leave far less open joint for moss and seed to take hold in. What re-sanding will not do is level sunken paving, fix a failed sub-base or stop weeds forever. If blocks have dropped or rocked, that is a laying issue for a paving contractor rather than a cleaner.
Surfaces this does not apply to
Permeable block paving uses a specified jointing aggregate rather than ordinary kiln-dried sand. I check the paving type before agreeing the cleaning and joint-replenishment work. Kiln-dried jointing sand is for suitable conventional sand-jointed block paving only — not concrete, tarmac, resin, porcelain, sandstone, slabs or any paving with mortar pointing. See patio cleaning and path cleaning for how those are handled.
Before you book
A wide shot of the whole area plus a close-up of the joints helps me assess the work. Photos help me assess the work. If the material, height, condition, access or drainage is uncertain, a visit may be needed before I confirm the scope and price in writing. More detail is on the driveway cleaning page and the block paving information page, and you can see results in our work.