Joe Simpson writes that with the correct selection of cleaning and maintenance products, caring for natural stone or tiled surfaces should be relatively straightforward. It will extend the life and preserve the value of the investment in these beautiful surfaces.
Enormous care goes into the manufacture and supply of natural stone, porcelain, and ceramic tile. Their individual aesthetics and formats are carefully engineered, along with their performance characteristics. However, when it comes to maintenance, these hugely varied materials are all too often viewed collectively as “tiles” … and treated in the same way.
This is a fundamental mistake. The care and maintenance regimes for “man-made” ceramic and porcelain surfaces – including sintered stone; conglomerates such a quartz solid surfacing; and each and every family of natural stone should be created individually.
In terms of the actual regime, they may follow similar paths, starting with the vitally important initial clean; but the products used in each case should be specific to the material being cleaned and, if necessary, sealed.
An initial post-installation clean, often referred to as a builder’s clean, is the vital first step in any effective maintenance regime. It will remove manufacturing debris and installation dirt, including any excess grout and adhesive.
This very important step should always be carried out before any sealer is applied. If you try to apply a sealer onto a dirty surface, it will not be properly absorbed. This will affect the performance of the sealer, and the overall surface aesthetic. What’s more, subsequent on-going maintenance will be more difficult.
To ensure that the correct cleaning product is used, it is vital to determine the acid sensitivity of the natural stone or other surface finish. If the surface isn’t acid sensitive, and if you have to use an acid detergent, it is generally good practice to choose a safe “buffered” acid-based cleaner, rather than a muriatic acid-based alternative.
Muriatic acid releases fumes that can harm both humans and the environment. They can also cause substantial damage to stainless steel and aluminium profiles. Buffered acids, on the other hand, do not emit fumes or cause erosion.
Certain materials, including polished marble, limestone and travertine, will not withstand an acid wash, and a pH-neutral or alkaline product should always be used. Alkaline products are effective at removing organic dirt and polymers from grouts and adhesives, but they are not suitable for polished stone tiles.
A safe selection, in all cases, is a pH-neutral cleaner. A concentrated product is a great option as it can be used at various dilutions to cater for most cleaning needs. Once the stone tiles have been thoroughly cleaned, the surface is then ready to be sealed.
Prevent, don’t cure
The fundamental maxim is that the best way to prevent stains on natural stone — or, indeed, any porous hard surface — is to treat it with a protective sealer. Sealers can repel spills on the surface, causing them to bead so that they can be wiped away before they have a chance to penetrate the stone.
Sealers generally fall into two basic categories: topical sealers and impregnating sealers. Impregnating sealers line the pores of natural stone, allowing the stone to breathe, while maintaining the natural stone’s strength. Impregnating sealers have a natural look and provide a barrier against oils and other liquid contaminants.
Some manufacturers have taken this impregnation technology a step further; using nano particles to create sealers that penetrate deeply into the treated material, providing what is billed as invisible, long-lasting protection.
Topical sealers, on the other hand, are hard-wearing surface sealers that provide a physical barrier, protecting natural stone or other surfaces from normal wear and tear. These sealers can have either a gloss or a matt finish. They can make the sealed area slippery when wet, and so anti-slip agents can be added, if required, to counteract this effect.
Some sealers can enhance (darken) natural stone, while others retain the stone’s natural hue. As a result, different stone types may require different grades of sealer, depending on the intended use, and the desired aesthetic.
Most natural stone and tile grout are cement-based, and porous. Because of this, sealant companies recommend sealing cement-based grout joints as soon as possible after installation to provide protection against water- and oil-based stains
Selection and application
Most natural stone surfaces will need to be sealed, to protect them from water, oil, and other contaminants. Some very porous stone surfaces may even need to be sealed before grouting. Treatments come in many forms, both water-based and solvent-based.
Water-based products offer a host of advantages and, compared with solvent-based formulations, many manufacturers claim that they perform equally well, or even better, than solvent-based alternatives. Water-based treatments can normally be applied over residual moisture and, somewhat surprisingly, tend to have faster drying times, cutting project time-scales.
What’s more, water-based formulations are now available to meet most required tasks: to protect from stains; to repel water; to enhance surfaces; and even block efflorescence.
As ecological considerations have become more of a priority on the political and social agenda, manufacturers have increasingly promoted water-based sealants. They are better for the environment and the tradespeople who apply them. In particular, they help limit the amount of VOCs (volatile organic compounds) released into the atmosphere.
With solvent-based treatments, application methods are different and drying times are extended. But surfaces have to be completely dry before a solvent is applied. Ventilation may also be required to extract fumes. There are still some heavy-duty sealers, particularly those for external applications, that are solvent-based. These can offer some application advantages, particularly for aerosol sprays.
Vanity tops and food preparation areas may need to have an impregnator applied. If required, users and installers should make sure that it is safe for use on food preparation surfaces. Product manufacturers will able to answer any questions.
Making a choice
Once natural stone or tiled surfaces have been sealed, cleaning is quite simple. Natural stone surfaces should always be cleaned with a product that is specifically manufactured to be sensitive to its unique mineral composition. For everyday cleaning, PH neutral cleaners, with a gentle formula, should be used to remove soiling. These cleaners can reinforce the original protective seal to help prevent future staining.
General spray-and-wipe style household cleaning products — that are not specifically formulated for natural stone or tile — should not be used. These formulations can break down the sealer, undermining its protective properties, and making the natural stone or grout joints susceptible to staining.
Many common cleaning products — including those that contain abrasives, lemon, vinegar, bleach, or ammonia — can actually etch away the polish, degrade the sealer, and discolour, or even scratch, the surface. Avoid using these products, and select alternatives that are scientifically formulated for use on natural stone and ceramic tile.
Of course, accidents do happen, and so most suppliers offer powerful formulations to cope with specific problems. For instance, professional-strength acidic cleaners can remove hard water deposits, grout haze, efflorescence, and soap scum. They are particularly suitable for use on ceramic and porcelain tiles. There are also professional strength, alkaline-based formulas that can remove even the most stubborn grease stains.
There are specific products designed to remove deep-set oil stains from natural stone surfaces, and formulas that can remove mould and mildew stains without degrading stone or grout. They are supplemented by polishes that add a brilliant shine to polished stone without leaving a greasy film, enhancers that can deepen the natural colour of stone while providing stain protection, and topical gloss finishing sealers that provide shine and deepen the colour of natural stone. These are particularly recommended for textured or tumbled natural stone.
Etch marks or water stains
Many common household items have the power to degrade a natural stone or tiled surface. One of the most vexatious is etching, which is the result of a chemical reaction that occurs when acid comes in contact with a susceptible surface. Etch marks on stone surfaces generally resemble water spots or a worn polish. These can be caused by orange juice, coffee, vinegar, wine, tomato products, mustard, and many common soft drinks.
All these liquids are highly acidic and can etch, dull, or discolour most marble, limestone, travertine, and cement-based grout. It is less well known that common toiletries such as perfume, mouthwash, and toothpaste can also damage a stone’s surface. Ceramic and porcelain tile, and acid-resistant stones such as granite, slate and sandstone are not usually affected.
Sealing can provide a vital window in which to wipe up a spill, but sealers may not stop the chemical reaction entirely, so it is best to provide a physical barrier for acid-sensitive stones.
While on-going maintenance tackles everyday dirt, grime, and atmospheric agents, some installations may also need a periodic deep clean to remove dirt build-up. Unsuitable maintenance products can undo everything achieved to this point. They will affect the performance of the sealer and can also damage the surface. For example, if an acidic cleaning product is used on an acid-sensitive stone, it will etch the surface. Likewise, an alkaline cleaning product used on a polished limestone will, over time, dull the surface.
Inferior products often leave residues behind, and many flooring treatments contain a “maintainer” that creates a surface shine. Over time, this builds up and becomes a key to dirt. If not addressed, the floor will become stained and, in extreme cases, a slip hazard can be created.
Just cleaning a natural stone surface with pure water is not a realistic option. However this is quite common, because fear of using the wrong detergent puts many people off using any detergent at all. If a surface is “cleaned” by mopping with water; this just mixes and spreads the dirt, which builds up and becomes trapped in the porosity of the stone. This creates a key for further dirt and the stone tiles become steadily harder to clean.
Once again, the safe option is a pH-neutral cleaner. Many products do not need rinsing at low concentrations and will not leave a residue.
Care and maintenance
Porcelain and ceramics are both man-made products and their care regimes are similar. Once again, an initial post installation clean should be carried out to remove and debris and installation dirt. Generally, buffered acid and alkaline detergents will be suitable.
When it comes to sealing ceramic and porcelain tiles, there are a host of conflicting views. Many people think that all porcelain and ceramic tiles don’t need sealing. However, with polished porcelain, micro-pores are opened up during the polishing process. As a result, many polished porcelains are factory sealed but this may be only sufficient to protect the surface during installation.
A further seal — after a thorough initial clean — is recommended, to protect the tile and grout joint. In addition, some very porous man-made tiles, like cement-based encaustics, will require sealing before and after grout is applied.
There are now water-based sealers that can be used on all stone and polished porcelain surfaces, and which offer other benefits including “food-safe” certification.
Many quartz surface manufacturers report that worktop discolouration often turns out to be stains held on the surface of the worktop by unnecessary topical sealants. Unable to penetrate the non-absorbent surface, they simply dry on top and provide a key for staining.
It is essential with quartz and other solid surfaces, as well as fully-vitrified porcelain and sintered stone, to always follow the surface manufacturer’s instructions when it comes to surface sealing.
On-going maintenance of porcelain and ceramics tackles the same issues seen in stone installations. Alkaline and pH-neutral detergents may be suitable, but pH-neutral cleaners are the safest option.
Inferior cleaning products which contain “maintainers” can be a big issue with porcelains and ceramics, especially those with textured finishes. They will leave a waxy shine on the surface and this will build up, attracting dirt. Very quickly, tiles will become stained by organic foot traffic and, in some cases, a slip hazard will be created. Also, on polished porcelain, the maintainer build up can cause the surface to dull, rather than enhance the polished finish.