Marble and natural stone floor care for commercial buildings

What marble and other natural stone floors are

A natural stone floor is quarried rock, sawn into tiles or slabs, set in mortar over the slab, and finished at the factory or on site. Nothing is printed, poured or pressed. The pattern and color are the rock itself, which is why two pieces from one block never look quite the same.

For cleaning purposes, the stones on this page fall into two families. The family decides which chemicals are safe and how the shine is kept.

• Calcareous stone is built mostly from calcium carbonate. Marble is limestone recrystallized by heat and pressure, dense enough to take a mirror polish. Limestone is the softer, more porous sedimentary parent, usually laid with a honed (matte) face. Travertine is a limestone formed at mineral springs, full of natural holes that are filled with cement or resin before the face is honed or polished. Acids dissolve all three.
• Siliceous stone is built mostly from silica minerals such as quartz and feldspar. Granite is the hard, crystalline example and shrugs off most household acids. Slate splits into thin layers and usually goes down with a textured cleft face rather than a polish.

The surface that daily care protects is the stone’s own face. A polished marble shine is not a coating; it is rock ground and buffed until it is smooth enough to reflect light. Honed stone is ground to a smooth matte instead. Many floors also carry an impregnating sealer, which soaks into the pores to slow staining but leaves nothing on top. Older lobbies sometimes still wear a layer of wax or acrylic that someone added years ago, and that film, not the marble, is what turns yellow and dull.

Where stone floors are used

Stone goes where a building wants to look permanent on the first step inside. In Northern and Central California these are the usual places:

• Hotels: lobbies, front desk areas, ballroom prefunction spaces and guest bathrooms, often polished marble with granite at the doors. Stone in guest areas is part of hotel and managed property floor care.
• Banks and office towers: street lobbies, elevator halls, executive floors and restrooms. Lobby stone sits inside a wider office floor care plan.
• Churches: narthexes, aisles, chancels and baptistries, where the marble or limestone is often decades old. Service timing around worship is in church and religious facility floor care.
• Event venues and clubs: foyers, grand stairs and bar fronts. Turnarounds between bookings are covered by event venue floor care.
• Medical buildings: main lobbies and the public corridors of newer hospitals and surgery centers. Clinical areas around them follow medical facility floor care.
• Retail and dining: jewelry and luxury stores, mall entries, and slate or granite in restaurant dining rooms and patios. Stone near storefronts and tables fits shopping center and retail floor care and restaurant floor care.

Inside the building, stone is concentrated at the entrance, the elevator core and the restrooms, with carpet or resilient tile taking over in the offices and rooms beyond. Slate and flamed granite also run outdoors onto plazas and covered entries, which means the same tiles see rain, leaves and sidewalk grit.

The stone care schedule, interval by interval

These lists suit a stone floor with moderate traffic, such as an office elevator hall, a hotel’s upper-floor landing or a church aisle used through the week. Adjustments for busier and quieter floors follow.

Daily

• Dust mop with a clean, untreated microfiber or cotton mop. Oil-treated mops leave a film that darkens stone and makes polish slippery.
• Damp mop traffic areas with a neutral cleaner labeled safe for stone, changing the water often so dirty solution is not spread back over the floor.
• Wipe spills right away, starting with coffee, juice, soda and wine on marble, limestone and travertine, before the acid has time to etch.
• Vacuum the entrance mats and lift them to clear the sand that collects underneath.
• Check restrooms around toilets and urinals, where acidic restroom products and urine attack marble first.

Weekly

• Machine scrub the lanes with a soft pad and neutral solution, picking it up with a wet vacuum or a small auto scrubber so water does not sit in grout joints or travertine holes.
• Clean the edges and corners by hand, where dust mops and machines leave a dark band.
• Dry buff polished marble with a white pad on a floor machine to keep the reflection between polishings.
• Scrub slate and flamed granite at the entries with a brush, since their texture holds soil that mopping skips.

Monthly

• Scrub the full floor wall to wall, including under movable furniture and planters.
• Walk the floor with a light at a low angle and note etch rings, scratched paths, chipped edges and darkened grout.
• Clean grout lines in restrooms and entries; the grout cleaning guide explains why joints darken first.
• Check felt pads under chairs, stanchions and planters, since metal feet scratch and rust on stone.

Quarterly or twice a year

• Polish marble traffic lanes with a marble polishing compound or fine polishing pads under a slow machine, bringing back the reflection in the paths before wear spreads.
• Deep clean slate, granite and honed limestone with a stone-safe cleaner suited to the soil, followed by a full rinse and extraction.
• Water-test the busiest lanes. A spot that darkens quickly has lost its sealer, so resealing goes onto a stone restoration specialist’s calendar.

Yearly or restorative

• Polish the whole marble floor edge to edge, including the quiet rooms that skipped the quarterly cycle.
• Deep clean every stone area and its grout, then photograph the result so next year’s walkthrough has a baseline.
• Call a stone restoration specialist for scratches a fingernail catches, deep etching, lippage between tiles, cracked or hollow tiles, lost travertine fill and resealing. Honing and grinding remove stone, so they are planned years apart rather than every year.

How traffic changes the intervals

• Heavy (hotel and bank street lobbies, hospital front doors, transit-facing entries): dust mop at least twice a day and more often in the rainy months, damp mop daily, buff two or three times a week and polish marble lanes every quarter.
• Moderate: follow the lists above, with lane polishing twice a year.
• Light (a chancel, a boardroom foyer, a guest bathroom): dust mop daily, damp mop two or three times a week, buff monthly and polish once a year.

Rain, loading docks and a door that opens onto a parking lot move a floor up one level, because each of them brings in more grit. To fit stone into a building-wide plan, see how often to clean commercial floors.

Signs the floor needs more than routine care

• The traffic lanes stay flat and grey after buffing, while the marble along the walls still reflects.
• Clear rings or dull spots show under a raking light where drinks, plants or cleaners sat.
• A yellow or cloudy film builds up in corners, a sign of an old coating rather than the stone.
• Water dropped on the floor soaks in and darkens the stone within a few minutes.
• Grout is visibly darker than the tile, or the joints are cracked and low.
• Travertine holes have opened up, slate layers are flaking, or tiles sound hollow when tapped.
• Edges of neighboring tiles stand at different heights and catch heels and carts.

The first two signs are the usual call for marble polishing. Coating buildup, worn sealer, open fills, hollow tiles and uneven edges are work for a stone restoration specialist, who hones, grinds, fills and seals.