Stone grinding and lippage removal

Why grinding and lippage removal is needed

Grinding is the stage nobody asks for on a quote but that plenty of London floors genuinely need. When tiles have been laid with visible height variation between them, walking across the floor feels uneven, cleaning cloths catch on the raised edges, and no polish, hone or deep clean will give a consistent finish until the high points are brought down to the plane of the surrounding tiles. That process is lippage removal, and it is done with metal-bond diamond grinding pads, working through a sequence that flattens the whole floor to a single even level.

The underlying cause of lippage is usually either a tile installation that never achieved a proper setting bed, a floor that has moved and settled over decades (common on period properties in London where ground conditions have shifted), or more recently the increasing use of large-format porcelain in new-build apartments, where the sheer tile size makes factory-tolerance variation visually obvious. Whatever the cause, the result is the same: a floor that trips the eye, collects dirt along every raised edge, and cannot be finished evenly without grinding. Left untreated, lippage also accelerates grout damage, because the raised tile edges take all the foot-traffic wear that the grout should share.

Signs your stone may need grinding

• You can feel raised edges between tiles when walking in socks or bare feet
• Dust and dirt visibly collect along the grout lines even after cleaning
• Raking light across the floor shows a clearly uneven surface, like small ridges
• Adjacent tiles reflect light at different angles
• Grout is cracking or failing along specific tile edges
• Large-format porcelain tiles (600mm and above) look visibly uneven at the joints
• A previous contractor has honed or polished the floor but the finish still looks patchy
• A period terrazzo installation has lost its flatness and the aggregate sits at different levels across the room

Suitable stone types and settings

We grind and level terrazzo (period Italian terrazzo almost always needs a grinding stage during restoration because the aggregate has settled over decades), marble (where tiles have lifted, shifted, or been badly installed), limestone (flagstone floors with uneven riven surfaces that the client wants flattened), large-format porcelain (increasingly common in new London kitchens and reception rooms, where lippage between 1200mm tiles is near-impossible to hone out), and granite (rare, because granite is too hard for quick grinding, but possible for specific damage). Sandstone and slate riven flagstones are not suitable candidates for grinding because their original texture is the point of the specification.

There is a limit to what grinding can do. Every tile has a finite thickness, and once the top four or five millimetres have been ground off, you are into the body of the stone where polishing response changes. We measure tile thickness at multiple points before quoting. If the lippage exceeds what grinding can safely remove, the honest answer is tile replacement, not grinding, and we will tell you that in writing before any work starts.

Results and expectations

A properly ground floor is flat, even, and visually calm for the first time since it was installed. The grout lines read as intentional detailing rather than as raised ridges. The finish that sits on top (honed or polished) is consistent across the whole room. Two honest caveats. First, grinding is a one-off intervention. It cannot be repeated many times on the same tiles without running out of stone. Second, grinding always flows into honing in the same visit. There is no point flattening a floor to 50 grit and leaving it, it will look worse than before. The sequence is always: grind flat, hone to close the surface, hone to final grit, seal.

When to choose a lighter service instead

If your floor is not genuinely uneven (no lippage you can feel, no raised grout edges), grinding is heavier than you need. Stone polishing or stone honing will correct dullness, etching and surface wear without touching the underlying plane of the floor. If the problem is appearance rather than flatness, deep cleaning is usually the correct first stage. Grinding is specifically for floors where the tiles themselves do not sit at the same level, and should not be used as a default restoration method on floors that do not need it.

Why choose us for stone grinding

Grinding is the highest-risk stage of stone restoration. Over-grind, and the tile is permanently thinned and compromised. Under-grind, and the lippage remains and the honing stage cannot finish evenly. The skill is in measuring before cutting, taking light passes across the whole floor rather than deep passes in one zone, and knowing when to stop. Marius is on every grinding job personally, we do not subcontract any part of the grinding stage, and full negative-pressure dust extraction is fitted on every grinding visit without exception. We document tile thickness before and after grinding on file. We are fully insured for residential, heritage and commercial work, and we routinely write method statements and programme paperwork suitable for main contractors, architects and conservation officers.

Areas we cover

Our grinding work in London covers Bloomsbury, Marylebone, Mayfair, Belgravia, Kensington, Chelsea, Islington, Holland Park and the wider centre of the city, plus new-build apartments in King's Cross, Paddington, Battersea and selected projects in the Home Counties. See areas we cover for the full list.