Most grout should be sealed. There are various types of sealers that offer different benefits. This article will help clear up any confusion you have and help you to make an informed decision for your own grout sealing needs.
First, when I say most grout should be sealed, what does that mean exactly? I mean all grout except epoxy grout and grout that is already sufficiently sealed needs to be sealed. How do you know if you have epoxy grout or if your grout is sufficiently grout? There is an easy test you can do. Spill a few drops of water on the grout. If it goes into the grout rather than beads up on the surface, your grout needs to be sealed.
In order to keep your new grout or newly cleaned grout clean, it should be sealed to help keep it clean. There are so many sealers on the market today. Which ones are best? Which ones really work?
It can be very confusing trying to choose a sealer to protect grout. In the past several years the janitorial industry have bombarded the market with hundreds of products to seal and protect grout. Fortunately, all of these products fall into only three major categories:
- Impregnators or penetrating sealers
- Color Sealers
Coatings are sealers that place a sacrificial coating on the surface of the grout. This is a film that lays on top of the grout acting as a barrier to prevent water, oil and dirt from entering the pores.
Coatings can be classified into two general types:
Strippable coatings are coatings that are designed to be easily stripped or removed from the surface of the grout. These coatings are made of polymers consisting of
acrylics, styrene, polyethylene and others. They are usually water based. Many of the janitorial products are water based polymer type coatings. To identify these
coatings look for terms on the label such as “metal cross link,” “high solids,” “high speed,” “acrylic”, “thermoplastic”, etc. When in doubt, ask. There are hundreds of different formulas of strippable coatings.
Permanent coatings are coatings that are very difficult to remove. They are made of solvent-based polymers such as polyurethane, epoxies, etc. These are not
recommended for grout.
Impregnators or penetrating sealers
Impregnators are designed to penetrate below the surface of the grout and deposit solid particles in the pores or to coat the individual minerals below the surface.
Water, oil and dirt are restricted from entering. Impregnators can be solvent or water based and usually contain silicone, siloxane, silane, methyl silicate or other similar silicon derivatives as well as Fluro alphatic polymers.
Impregnators can also be classified into two types:
- hydrophobic (water repelling)
- oilophopic (oil repelling)
Hydrophobic impregnators are designed to repel only water and water based chemicals. A hydrophobic impregnator would repel fruit drinks, coffee, tea, soda,
Oilophobic impregnators are designed to repel water and oil based liquids. Cooking oil, grease, body oils, etc. would be repelled by a oilophobic impregnator.
An oilophobic impregnator will always be hydrophobic, but a hydrophobic impregnator may not be oilophobic. Be sure to read product labels carefully to
determine if they are hydrophobic or oilophobic. Some products are listed as oil resistant. Oil resistant and oil repellant are entirely different. Oil resistant will
only slow down the absorption of oil into the grout. Oil repellant will prevent oil from entering the grout. Again, read product labels carefully. Be sure you are
buying the right product for your particular situation.
COATING OR IMPREGNATOR?
How do you make the determination between a coating or an impregnator? They both have their advantages and their disadvantages. The following summary
should be studied carefully when choosing the proper product:
Coatings are sealers that place a protective, sacrificial layer on the surface of the grout.
1. Coatings are generally economical. The initial application is relatively low.
2. Coatings are difficult to apply since you must apply them with a brush or
applicator, which can be very tedious.
3. Coatings generally will provide a sacrificial coating. This layer will take most
of the wear, preventing wear of the grout.
1. Since most coatings are typically softer than the grout itself, they will usually scratch, mar and scuff very easily, showing traffic patterns soon after application.
This will require re-application.
2. Coatings can build up and can cause an unsightly appearance, producing an unnatural look.
3. Poor quality coatings can turn yellow. This is especially true if the grout is exposed to UV light.
4. Coatings require frequent stripping and reapplication. The chemicals and abrasives used in the stripping process may cause damage to the grout. Typically,
certain stripping pads and stripping brushes can also cause damage.
5. Certain coatings may block the breathing capability of the grout. Moisture can become trapped below the surface and may lead to the grout falling apart
1. Most impregnators will not change the appearance of the grout.
2. Most impregnators do not require frequent applications. Since the impregnator
is below the surface, it will generally last several years before reapplication is
3. Most impregnators are not affected by UV light since they are below the surface where UV light cannot penetrate. For this reason they can be used outdoors.
4. Impregnators are typically hydrophobic, while some are oiliophobic.
1. Impregnators that are solvent-based produce noxious and flammable vapors
2. Solvent-based impregnators are harmful to the environment producing high
VOC (volatile organic compounds). For this reason, some are restricted in certain states. Always check the MSDS sheet.
3. The initial cost of most impregnators is relatively high.
5. Impregnators in general cannot be used below grade to resist hydrostatic
When choosing the proper product for protection, the above guidelines should
help. Always talk with the manufacture or distributor, and let them know where
you plan to use their product. They can be very helpful if you tell them all the
conditions that apply.
Color sealing is another process which not only seals your grout but also colors it. This option is the optimal choice if the grout is so soiled it wont come clean or you
wish to change the color of your grout.
While cleaning and sealing can be a do it yourself project, it can get tricky and if you use the wrong cleaner or sealer you take the chance of not only damaging your
grout but also your tile. I would highly recommend that you contact a pro. This way the process will be done correctly and will last a lot longer.