Much of Boston's housing is decades old, and so is a lot of the tile inside it. Add a long snow season and you get two kinds of grout trouble: tired joints in bathrooms that were tiled generations ago, and entry floors that take a beating every winter. This page explains both, and what cleaning, sealing and color sealing can do for each.
A city of older homes
The Census Bureau counts 310,625 housing units in Boston, with a median year built of 1947. Only 12 percent of them are detached single-family houses. The rest are attached homes, apartment buildings and condos, where one building can hold many bathrooms of very different ages.
In ZIP 02108 the numbers are starker still. The median home there was built in 1939 or earlier, and just 1 percent of its 2,568 housing units are detached houses. Tile in buildings of that age has usually been patched, partly redone or covered over at least once.
Bathrooms from the first half of the last century were often tiled with small hexagon or square mosaics on the floor and subway tile on the walls. Small tile means far more grout than a modern large-format floor of the same size. More grout means more surface for dirt, and a floor that looks dingy even when the tile itself is fine.
Old grout is also uneven. Repairs over the years leave patches in slightly different colors, and some joints have worn below the tile edge. Cleaning lifts the dirt from all of it. If the patchwork still shows after cleaning, Grout Color Sealing puts the whole floor back to one shade, which suits a classic white or gray mosaic well.
Snow, slush and the entry floor
The NOAA normals station at Boston Logan Intl AP, MA, about 3 miles away, records 49.2 inches of snowfall in an average year, on top of 43.6 inches of total precipitation. The first fall freeze comes around November 9 and the last spring freeze around April 4, so the winter season is long.
Through those months, boots carry slush, grit and the salt spread on winter sidewalks straight onto vestibule and hallway tile. When the slush dries, it leaves a white crust on the floor. That crust is salt, and it soaks into unsealed grout along with the dirty water it came in.
Salt left in grout pulls in moisture and keeps the joints damp. It can also slowly break down the cement surface, so the grout turns rough and sandy at the busiest spot inside the door. Mopping with plain water moves the salt around rather than removing it.
A spring clean after the last freeze is the right timing for most entry floors. The crew dissolves the salt residue, scrubs each joint and extracts the rinse water so the salt leaves the floor. A sealer applied afterwards makes next winter's residue easier to wipe up before it soaks in.
Spring mud and fine silt
The USDA soil survey describes the top soil layer at the center of ZIP 02108 as silt loam, in the well drained class, with the ground there at about 80 feet of elevation. Silt is a very fine soil. When it is wet it sticks to shoes and stroller wheels, and when it dries it turns to a dust that settles into every low joint on a tile floor.
Snowmelt in early spring brings the most of it indoors. Thawing yards and tree pits along the sidewalk turn soft, and fine mud rides in on the same boots that carried salt all winter. On unsealed grout the silt soaks in with the water and dries as a brown tint that a mop will not shift.
A deep clean loosens that tint and lifts it out with extraction. For floors right inside an entry, sealing is the step that changes the most, because sealed grout keeps silt and water at the surface. A dry mop or vacuum after a wet day then picks most of it up before it has time to settle in.
Soft water, but soap still builds up
Boston gets its water from the Massachusetts Water Resources Authority (MWRA), supplier to Boston Water and Sewer Commission. The supply has a hardness of approximately 16 mg/L, or 1 grain per gallon as calcium carbonate, which is in the soft class.
With water that soft, soap residue darkens shower grout far more than mineral scale does. Soft water makes soap lather well and rinse slowly, so a film of soap and body oil stays on the walls and settles in the joints. Dust and skin cells stick to the film, and the grout goes gray.
Our cleaner for that film is alkaline, which is what breaks down soap and oil. It goes on, sits for a few minutes, and then every joint gets brushed by hand before the extraction rinse. A shower that looked like it needed regrouting often comes back close to its first color.
Kitchen grout gets a different mix. Cooking oil drifts onto backsplash and floor tile and hardens into a sticky layer, and in an older apartment with a small kitchen that layer reaches every surface near the stove. The crew pre-treats grease with a degreaser before the general clean, since a standard grout cleaner slides over oil without cutting it. Backsplash joints are brushed by hand and wiped rather than flooded, so water does not run down behind the counter.
Heated rooms and hairline cracks
The Logan station counts 92 days a year with a low of 32 F or colder. Through those days the heat runs, and indoor air dries out. Tile and grout expand and shrink a little as the building warms and cools, and old buildings move more than new ones as their framing settles.
The result shows up as hairline cracks in grout, most often along the edge of a tub, at the base of a wall and over the joints in a wood subfloor. A crack needs a repair. Cleaning will make the area look better, but water can still get through the crack and reach the materials under the tile.
The crew will point out cracked or loose joints during the visit. A few cracked lines can be cut out and refilled as part of Regrouting and Tile Repair, which we quote after seeing the work. The corners where a tub meets the wall should be caulk rather than grout, since caulk flexes with the movement and grout does not.
Marble thresholds, stone vanities and other care
Bathrooms from that era often pair ceramic tile with a marble threshold, a marble sill or a stone vanity top. Stone needs a stone-safe method. Acid cleaners and vinegar etch marble, leaving dull spots that no amount of polishing at home will fix, so we never use them near stone.
When we clean a floor that meets a marble threshold, the crew protects the stone or switches to a neutral cleaner along that edge. Tell us about any stone when you book, including on walls, so the right products come with the crew.
For condo owners and landlords, Shower and Tub Grout Cleaning before a move-in or a sale is a quick way to make an older bath look cared for. Pair it with Grout Sealing and the next tenant or owner starts with grout that resists stains from day one.