Cleaning, repointing or relaying?
These are three different jobs, and knowing which one you need is the first step to a sensible price. Cleaning deals with the surface: dirt, moss, algae and staining. Repointing deals with the joints between the slabs, raking out what has failed and filling them again. Relaying deals with the base, lifting the slabs and rebuilding what is underneath. Most tired patios need the first two together. Only a patio that has sunk or rocks across a wide area needs the third.
Patio size and layout
A larger patio takes longer, but the shape matters as well. A simple rectangle of large slabs has fewer joints to rake out and fill than the same area laid in small modules or a mixed pattern. Steps, edges, curved sections and areas around drains and walls all add detail work. Getting equipment into the garden and the waste out again also plays a part.
Stone type and how it reacts to cleaning
Different stones need different handling. Porcelain and dense concrete slabs are hard wearing and take a firmer clean. Sandstone and other natural stone have a softer face that a harsh jet can mark, so they need a gentler, slower approach to come up well without damage. That extra care takes time, which is reflected in the work involved.
Patio cleaning and repointing
- Slabs cleaned to suit the stone, not blasted
- Old, cracked or missing joints raked out
- Loose or rocking slabs lifted and re-bedded
Joint condition
How much of the old pointing has to come out is often the deciding factor. A patio with a few cracked joints is a quick job. One where the mortar has crumbled or washed out everywhere needs every joint raking out to a sound depth before it can be refilled, and that is slow, careful work. Wide joints take more material than narrow ones. The choice of new jointing, mortar or a brush in compound, is discussed on site; our jointing guide compares the two.
Moss, algae and weeds
A patio in shade, under trees or against a north facing wall usually has heavier growth than one in full sun. Thick moss and established weeds in the joints take longer to clear, and the roots need removing from the joints before repointing, otherwise they grow straight back through. Our guide to weeds in patio joints explains why they appear in the first place.
Loose or rocking slabs
A few slabs that click or move underfoot can usually be lifted, given a fresh bed and set back to level as part of the restoration. Each one adds time. If, once lifted, the ground underneath is soft or wet across a wide area, that points to a problem with the base rather than the surface, and it changes the job.
When relaying is better value
Cleaning and repointing a patio that is failing underneath spends money on a surface that will move again. If the patio holds water against the house, has dipped in the middle, or rocks across most of its area, relaying is usually the better spend over time. Good slabs can often be cleaned and reused, keeping the look. Ashley visits, checks the levels and drainage, and writes up which job the patio actually needs before any work starts.