Tile Ghosting

After old VCT (vinyl composition tile) has been removed from a concrete substrate sometimes lines that mirror the former location of the tiles appear during the early grinding steps. These lines or tile marks are called tile ghosting. Tile ghosting comes from moisture vapor transmission within or below the slab, from water and treatments applied on the former VCT above the slab, or both. The most common questions about tile ghosting are:

 

Will we be able to grind through these lines?

If the marks are from the top down as with marking from dirty or gray water, we can often grind off or shave off or at least minimize the presence of the tile marks. But if the marks are caused by vapor transmission up through the slab, then no matter how far down we grind, we will just keep finding the same lines, though perhaps wider and even more pronounced.

Will coloring the concrete hide the marks?

Coloring the concrete may help give the concrete more of an even tone, but although that may be interpreted as masking or covering up the issue, the truth is that the lines are still going to be visible.

Will the marks fade over time or are they permanent?

No, the marks will not fade over time and yes, they are permanent.

If I can’t live with these marks and still want the “look” of polished concrete what are my options?

Short of removing and replacing the current slab you have one option. We can prep-grind the surface, apply an epoxy primer, apply a polish-able concrete topping and finally polish that topping to the desired specifications.

Tile Ghosting Causes

Tile Ghosting
Causes

Tile marks or tile ghosting are caused and affected by moisture intrusion. These lines can (1) come from within or below the slab, or they can develop (2) from processes or treatments applied on the VCT above the slab.

(1) Moisture vapor transmission through a concrete slab is caused by the need for the moisture to reach equilibrium, which is achieved when all parts of the system have the same amount of moisture content. When the ground below the slab is very wet and the concrete above it is not, the water will travel from the ground up into the slab because the slab is drier. Then the water will again seek a drier space. Heating and cooling systems control the temperature and humidity of the air in the rooms, and as moisture is removed from room air, the moisture in the slab will naturally move up through the tile seams toward the dry air. The moisture in question may be from within the slab itself as the normal amount of water needed to place the concrete. It can also come from a source underneath the slab, such as a high water table, a leaky pipe, or a sprinkler system.

Movement of salt-laden water up through the slab is the same phenomenon that causes traditional efflorescence issues with concrete and masonry. Moisture migrates up according to the laws of physics, always seeking equilibrium, while dissolving and carrying along free lime, calcium hydroxide and salts that have not reacted during the curing of the slab. When the salted water evaporates at the slab surface, it leaves the salts behind, which form an ever-widening line. As long as there is a continuous supply of water to the concrete, there will be moisture transmission, and the tile marks will continue to develop.

(2) Topical processes or treatments are the other major source of tile marks. The quality of the tile installation itself is a major factor, as is the janitorial treatment of the area. Are all of the tiles tight against one another or is there visible space? Were multiple coats of floor finish applied prior to opening? Did crews prevent janitorial liquids from puddling on the floor for extended time periods? All of these factors help determine the amount of lines and whitening that occurs during years of routine janitorial maintenance procedures.

Washing, waxing, stripping and re-waxing are processes that can drive a steady stream of water directly into the concrete surface. Puddles of chemicals and dirty or gray water are allowed to dwell on the floor and seep down through the seams into the concrete slab. Gray water with its residual chemicals soon becomes trapped underneath the tile by subsequent applications of wax and high-speed burnishing. When gray water manages to escape through the tiles’ gaps and seams, it will leave behind the insoluble salts at the surface of the slab: our old nemesis, efflorescence.

As the salts are dissolved from within the slab and moved up to the surface, the body of the concrete loses its free salts and becomes even more porous as a result, allowing yet more gray water to penetrate. This repeated cycle of soaking, dissolving salts, movement of salts to the surface, evaporation of water, and deposition of salty residue at and near the surface helps creates the tile mark problem.

Recommended Cleaner

Recommended Cleaner
Mechanically Polished Concrete

A diamond ground & honed concrete floor is durable, functional and easy to maintain. To better clean and maintain your floor Supreme recommends the use of Ameripolish PoliSmart CS Rejuvinating Cleaner. PoliSmart CS is a neutral cleaner that will not damage the surface as do acidic or high alkalinity cleaners. It also contains trace amounts of the ingredients contained in Ameripolish 3D HD, the silicate hardener / densifier that was used to produce your floor. In addition, it also contains stain blocking additives. Each time you clean with PoliSmart CS you will be reinforcing the abrasion and stain resistance of your floor. You may acquire PoliSmart CS from United Surface Preparation.

CONTACT INFORMATION

Mike Heintz
mike.heintz@unitedsurfprep.com
763-315-6730

United Surface Prep
900 Lund Blvd
Anoka, MN 55303

1-800-322-1413
763-424-7400

NOTE

• For best results, add no more than 1-2 ounces of PoliSmart CS per one gallon of water

• For best results, fit cleaning, buffing and burnishing machines with HTC Twister Pads

• For further information, see Care & Maintenance or contact Supreme Systems

Care & Maintenance • Mechanically Honed Concrete

Care & Maintenance
Mechanically Honed Concrete
with Ameripolish™ SR• Stain Protection

A diamond ground & honed concrete floor with Ameripolish SR• Stain Protection is durable, functional and easy to maintain. Your care & maintenance schedule will depend on the flooring environment and individual circumstances.

 

CLEANING

Regular dry and wet cleaning is the basis of your program.

1. Vacuum or dust mop floors daily. A microfiber dry mop works best. Walk-off floor mats placed at exterior entrances help alleviate abrasive dirt, salts, etc. from being introduced onto the surface.

2. Deposits from spills should be removed as soon as possible.

3. Wet clean floors at least once a week. Heavy traffic floors may need to be cleaned more frequently. Use recommended cleaning product for best results. Use loop end wet mops or microfiber wet mops for damp or wet mopping. For better results use automatic floor machines fitted with diamond impregnated pads. Turn off ionizer switch to avoid early deterioration of floor. Never use Pine-Sol or products containing ammonia, bleach, citrus or vinegar. Never use acidic or highly alkaline cleaners. Do not use “Swiffer Wet-Jet” type cleaning equipment.

 

BUFFING & BURNISHING

For better results than a cleaning program only, you can periodically machine your floor with a diamond impregnated pad.

1. Buffing with a (175 rpm) floor machine

2. Burnishing with a (1500 rpm) floor machine

 

EXTENDED MAINTENANCE

At some point, whether because of heavy traffic or neglect, your floor may deteriorate beyond the capabilities of a cleaning program with periodic buffing and burnishing.

1. Chemical – A reapplication of SR• with high-speed burnishing will protect and extend the chemical and water resistance of your floor. SR• does not require mechanical preparation before reapplication.

2. Mechanical – A planetary grinding machines fitted with diamond tooling can be used to restore a visibly worn floor.

Care & Maintenance • Polished Concrete

Care & Maintenance
Polished Concrete

Mechanically ground, honed & polished concrete floors are one of the most beautiful, durable and functional surfaces on the market today. Your care & maintenance schedule will depend on the flooring environment and individual circumstances.

 

CLEANING

Regular dry and wet cleaning is the basis of your program. How well a program is established and followed directly affects how long before buffing, burnishing or extended maintenance is needed.

1. Vacuum or dust mop floors daily. A microfiber dry mop works best.

• Walk-off floor mats placed at exterior entrances help alleviate abrasive dirt, salts, etc. from being introduced onto the surface. Walk-off mats should be maintained and kept clean.
2. Deposits from spills should be removed as soon as possible.

3. Wet clean floors with recommended cleaner at least once a week. Heavy traffic floors will need to be cleaned more frequently.

• Use automatic floor machines if possible, for best results. Only soft bristled brushes, white buffing pads or diamond impregnated pads should be used. Turn off ionizer switch to avoid early deterioration of floor.

• Loop end wet mops are excellent for damp or wet mopping. Microfiber wet mops also work well.

• Use recommended cleaning product for best results. Never use Pine-Sol or products containing ammonia, bleach, citrus or vinegar. Never use acidic or highly alkaline cleaners on your polished floor. Do not use “Swiffer Wet-Jet” type cleaning equipment.

 

BUFFING & BURNISHING

For better results than a cleaning program only, you can periodically buff or burnish your floor.

1. Buffing with a (175 rpm) floor machine fitted with a white or diamond impregnated pad can be used to prevent early deterioration and maintain the gloss.

2., Burnishing with a (1500 rpm) floor machine fitted with a diamond impregnated pad can be used on the floor to remove microscopic scratches and improve the gloss.

 

EXTENDED MAINTENANCE – CHEMICAL & MECHANICAL

At some point because of neglect or heavy traffic your polished concrete floor may dull and abrade beyond the capabilities of a cleaning program with periodic buffing and burnishing.

1. Chemical – Reapplication of protective treatments will prevent early deterioration and the need for mechanical refinement.

2. Mechanical – A planetary grinding machine fitted with diamond-bonded polishing tools can be used to restore a visibly worn floor that is in need of mechanical refinement.

Expectations

Expectations for a crafted concrete floor

If you are looking for a unique floor that is beautiful, functional and durable, polished concrete by Supreme Systems is a good choice for you. However, it is not factory produced. It is a site crafted floor with imperfections, inconsistencies and variations that should be expected and enjoyed. If you want or need uniformity a processed polished concrete floor may not be for you.

All concrete reacts differently. Due to the many variables involved, including age, natural materials and previous service of the concrete each slab will have unique characteristics. A polished concrete floor will not be aesthetically uniform throughout the surface, along edges, in corners or underneath objects. For example, aggregate exposure may vary from areas with large aggregate exposed to areas with small to no aggregate exposed depending on the flatness and hardness of the floor.

Final results of a polished concrete floor are largely dependent on the concrete we are given to work with. Therefore, when there is an opportunity to specify mix, placement, finishing, curing, joint placement and surface protection the final product can turn out significantly different than if only the processing procedures are specified. On an existing floor removal of adhesives, coatings may need to be performed before final design and specification of process and materials is possible. If repairs are necessary patching & filling materials cannot be made invisible and will be noticeable in the finished floor No sample can be exactly matched and should be considered merely representative of color, finish level and aggregate exposure. An onsite mock-up will better represent the final product although variations may still be found throughout the floor.

Step One

To be done well, a processed & polished concrete floor requires a lot of time and effort. The first step being the slowest of all steps can account for anywhere from 20% to 80% of the total time spent on crafting a finish. On average, step one will account for 40% to 60% of the time to complete a polished finish.

 

Five operations that can make up step one

• Plane Grinding of extreme uneven areas to achieve a relatively flat and level surface capable of being processed with a planetary machine.

• Removal of material such as adhesives, coatings and toppings

• Repair – Patching & Filling of joints, cracks, spalls, etc.

• First Grit Grinding – The starting grit is the foundation for an attractive and durable finish. Multiple grinds/passes are performed to properly flatten and prepare the floor for further process grinding

• Hardening & Densification – Application of chemical treatment(s) for increased wear, water & chemical resistance and a superior looking finish

 

Factors that determine how long it will take to complete step one 

• The amount of plane grinding required

• The type and amount of surface material to be removed

• The type and amount of repair required

• The smoothness and flatness of the slab from casting

• The hardness/softness of the slab

• The amount of edges and corners

• The size of the grinding machine and type of tooling that is used

The Supreme Way

“Art is not a mirror to reflect the world, but a hammer with which to shape it”

Bertolt Brecht

The Supreme Way

Supreme Concrete Floors
Supreme Systems, Inc.
Minneapolis, MN
612-382-4448

 

Polished Concrete or Processed Concrete?

When referring to polished concrete floors much of the terminology used is incorrect. Polished concrete is often used to describe an exposed concrete floor with a “shiny” finish. While a “shiny” exposed concrete floor may or may not be polished concrete a better and more precise definition would be mechanically processed & polished concrete.

A polished finish is one of the end results of a processed concrete floor. The act of producing a mechanically-processed polished-finish involves three stages: grinding, honing and polishing. Each step is broken down into multiple steps, consisting of consecutively finer grit abrasives. Not all mechanically processed concrete can be called polished concrete. Ground concrete consists of steps using 100 grit resins or below. A ground finish has a flat appearance with no or very little reflection. Honed concrete consists of steps using 100 grit, 200 grit or 400 grit resins. A honed finish has a matte appearance with a slight clarity of reflection.

Semi-polished or highly-polished concrete consists of steps using 800 grit, 1500 grit or 3000 grit diamond tooling. A polished finish has a gloss appearance with mirror-like clarity of reflection and is achieved by using one of three mechanically processed & polished concrete classifications; bonded abrasive, burnished or hybrid.

♦ Processed concrete is the act of changing a concrete floor surface by means of a multi-step mechanical operation that involves cutting and or refining the surface with an abrasive where each step cuts progressively finer microscopic peaks and valleys until the desired finish is achieved.

 

Mechanically Processed & Polished Concrete
Classifications

Bonded Abrasive – A mechanical grinding process using large industrial equipment where each step is performed using bonded-abrasive diamond-tooling.

Burnished – A mechanical friction-rubbing process using high-speed burnishing equipment where each step is performed using abrasive pads which may or may not contain industrial diamonds.

Hybrid – An operation using large industrial equipment, lightweight equipment, high-speed burnishing equipment or a combination of where steps are performed using bonded diamond-abrasives, abrasive pads or a combination of.

♦ Of these classifications, bonded abrasive produces the most beautiful and durable mechanically processed & polished concrete floors. They are easier to maintain and have lower long term costs than the other classifications. It is the classification Supreme Systems almost always recommends to our customers and most often installs.

∗ Note – Mechanically ground/honed and clear-coated concrete does not conform to a classification of mechanically-processed & polished concrete. It is the operation of applying a film-forming coating to a concrete floor surface to achieve a level of finished gloss. Typical film formers are acrylics, epoxies, polyurethanes and polyuria.

 

The Supreme Way
A commitment to excellence

Processed & polished concrete using bonded abrasives is one of the best bargains in the flooring industry today and has been called the “greatest floor on earth”. However, proper installation is truly an artisan craft, not simply a formulaic procedure. Becoming a master concrete processor requires years of experience and extensive training in concrete characteristics, nuances and conditions. It involves paying attention to how the grinder sounds, vibrates and moves. Awareness of techniques such as looking behind the grinder to evaluate whether the diamonds are cutting, whether the diamonds are cutting a complete scratch pattern, and recognizing an incorrect tooling bond are keys to a quality floor. We must monitor how the hardness, flatness and finish of the concrete effects the grinding. We must use sight, sound and touch to determine how the concrete is reacting to the diamonds, and we must decide how to prevent glazing, random scratches or other surface blemishes. We must understand what the concrete is telling us and discern which diamonds, chemicals or methods to use next in order to produce a beautiful, functional and durable floor. Experience and a commitment to excellence make the difference between a mediocre floor and the “greatest floor on earth”.

There is no shortcut to a successfully installed mechanically processed & polished floor. Incorrect specifications, substandard equipment and insufficient or improper chemical protection will mean that the floors longevity and low maintenance benefits cannot be delivered.

HTC is the leading manufacturer and supplier of concrete grinding equipment in the world. We use HTC machines, HTC diamond tooling, Ameripolish colorants, Ameripolish protective treatments and our methods and specifications to produce three bonded-abrasive polished finish concepts. A fourth concept leaves a mechanically honed finish and is not considered polished concrete.