Pssst! We're working on a new design for NACHI.ORG. Take a sneak peek.

Ceramic Tile and Stone Inspection

by Nick Gromicko

Ceramic tile and stone are popular flooring materials, but each is subject to damage if not properly maintained. Natural stone floors are durable, but vulnerable to common acids and dirt

Natural stone floors are durable, but vulnerable to common acids and dirt

Ceramic tile, due to its low required maintenance, ease of cleaning, and resistance to physical damage, is one of the most popular flooring materials available today. Made primarily from clay and other organic, as well as inorganic, materials, the tile is available in both glazed and unglazed finishes. Ceramic tiles are vulnerable to a number of defects, however, that can be inspected for the following issues:

uneven tiles. Examine the tiles to see how level they are in relation to each other. Uneven tiles probably weren’t set correctly in the mortar, and reinstallation may be necessary;
cracks, loose tiles and splitting. Cracks in ceramic tile are the result of movement in the tile underlayment, excessive expansion or contraction of the building during freeze-thaw cycles, abuse, or improper installation. Minor cracks can be repaired with grout that matches the color of the tile, but larger cracks may require replacement of the tile;
crazing. If tiles were cooled too quickly after kiln-firing, they can develop fine surface cracks, most often appearing as a fine, web-like network akin to cracked ice. Crazing is much more common in older, historic tiles than in modern tiles, but it still happens today. Crazing increases the rate at which tiles hold dirt, leading to discoloration; and
cracked or discolored grout lines. Unsealed or improperly sealed grout will readily absorb moisture from the air or standing water, especially around showers and sinks. Some types of porous tiles may actually powder or spall if subjected to constant moisture. Damaged or discolored grout can be removed and replaced.

Natural stone tiles have a beauty that is difficult to recreate. They add an air of elegance and character to any home. Stone is more durable than ceramic tile, too, as it’s less likely to scratch, and holds up well under foot traffic. The unique and complex patterns can appear busy and overwhelming in large, empty rooms, however. Stone is also more difficult to maintain than ceramic tile. The following maintenance and repair tips are recommended:

Apply an impregnating sealant. An oliophobic sealant will repel both oil and water, and it’s especially helpful in the kitchen. Try to use a solvent-based sealant, as they’re generally better than water-based varieties.
Quickly clean up any acids. Some of the more common stone tiles are marble and limestone, which are calcite-based, meaning that they will corrode when exposed to acids, such as vinegar or lemon juice. Unfortunately, sealants cannot protect stone against these substances, which will etch into the stone if left standing. Igneous stones, such as basalt and granite, as well as ceramic tile, are less vulnerable to acid damage.
Lay walk-off mats or area rugs on either side of exterior entrances and instruct people to wipe their feet before they enter the home. The main cause of surface scratching on stone floors is dirt from outside that becomes caught under shoes and scraped across the floor. Scratching can dull the stone’s natural polish and damage its natural crystals, causing it to lose its shine and reflection.
Use a good-quality stone soap, preferably one containing linseed oil, for regular maintenance and cleaning. In most cases, you can simply mop the soap and leave it to dry.

In summary, ceramic and stone can be superb flooring materials, but water, acid, improper installation, and other adverse conditions may create defects.

Acid Rain and Inspectors: Buildings at Risk

International Association of Certified Home Inspectors

Ceramic Tile and Stone Inspection

Popular Sections

All Sections

Inspection News

InterNACHI Membership

Inspection Standards

Inspection Education

InterNACHI Inspectors

Inspection Links