April 19, 2022
ARE STEAM CLEANERS SAFE FOR NATURAL STONE?There are many wrong ways to clean natural stone, which is why we recommend leaving heavy cleaning to an experienced stone restoration professional. As you will see in the following article from Fred M. Hueston, Chief Technical Director for SurpHaces and natural stone troubleshooting expert, steam cleaning should be used with care and sparingly, or better yet, not at all…
SpallingSteam cleaning can cause a condition known as spalling. Since most stone is porous, the high temperature of steam cleaning can cause pressure within the stone, which can lead to pitting and/or flaking of the surface of the stone.
Sealer RemovalNatural stone sealers inhibit staining. Impregnating sealers penetrate the surface of the stone. Color enhancing impregnating sealers intensify the colors in natural stone. Topical sealers form a strippable or permanent coating that covers the surface of stone. If natural stone is sealed, steam cleaning can remove the sealer.
Accelerated Crack DamageAs natural stone is fabricated, transported, and installed, stress on the material can cause cracks to form. Stone may also be cracked after installation because of accidental damage or environmental stresses. If natural stone has any cracks, the heat and pressure from a steam cleaner can cause the cracks to expand and open up, making the cracks more obvious and problematic.
Grout DamageGrout can also be negatively impacted by continuous use of steam cleaning. Damage may include discoloration and the grout cracking and falling apart. Steam cleaning may also remove sealers that were applied to the grout.
Iron OxidationIf the composition of your natural stone includes iron, steam cleaning poses a risk of discoloration. Moisture reacts with the iron, creating rust-like stains on and in the stone. Iron oxidation discoloration can be extremely difficult or even impossible to remove.
Filler DamageIf your stone has fillers (travertine, for example), steam cleaning can cause the fillers to pop loose and fall out.
Residential vs Commercial Steam CleanersHome-type steam cleaners may be safe to sparingly use on natural stone, since these steam cleaners do not reach the same high temperatures as commercial steam cleaners. The maximum temperature of residential steam cleaners is about 250 degrees F, whereas commercial steam cleaners can reach temperature of over 300 degrees F. However, even home-type steam cleaners should not be used often. Steam cleaning every few days, or even every week or two can result in damage. At most, you could use a lower temperature mop-style steam cleaner a few times per year.
Types of Steam CleanersThere are several types of steam cleaners.