Polished Concrete

The possibilities of concrete are endless.

You can choose the stone, the colour and the finish making polished concrete a versatile material to use in residential, commercial and industrial settings. Just let us know what your requirements are and we will craft a unique space that will come alive and awaken your senses.

Q: How is it done?
A: Diamond discs are mounted to a grinder. These rough grits remove imperfections while flattening the floor and or exposing the stones. Then finer grits are used to create a marble like shine. The process is usually an 8- 12 step process beginning with 25 grit diamonds and ending with 3000 grit diamonds and a high speed buffing.

Q: How long will it last?
A: This is a permanent process. There’s no wax, epoxy, acrylic, or any other shiny coverings applied that will eventually fail. When our company is finished the result is a bare concrete floor that has been permanently polished. In heavy industrial, commercial or institutional use, an inexpensive re-polish may be needed years down the road (depending on your maintenance).

Q: What maintenance is required?
A: Just routine mopping or a “walk behind” scrubber…nothing unusual.

Q: Is it slippery?
A: Yes and NO Depending on the degree of “shine” we that we attain. In wet and exterior areas we prefer to stop at CGS 100 which gives a “MATT” finish but has nice grip even when wet. We then do a CGS 3000 “Super shine” for interior use.

Q: What is the cost?
A: Price varies on size and condition of the concrete. Here are 3 typical examples where the concrete has been placed already:

a) Residential R240-00/m2

b) Warehouse, new construction, wide open area, good concrete job. R180-00/m2

c) Warehouse, 20-year-old concrete, cracks, pitting, paint and epoxy, just plain horrible. R300-00/m2

Q: Are there any harmful VOC’s?
A: No. This process is completely eco-friendly and perfect for green construction projects.

Q: Where are people using it?
A: Warehouses, Restaurants, Schools, Retail Stores, Manufacturing, Residential, Auto Showroom and Service Areas, etc.

Q: What about stains?
A: Cleaning is easy. Just mop up the mess. Some oily stains if ignored will soak into the pores but will come back out over time.

Q: Do forklift tires mess it up?
A: No. Marks wipe off easily.

Q: What about 75-year-old concrete that is pitted, well worn, or has had coatings applied?
A: No problem. When we’re finished, your floor will be gorgeous.

Q: Can the shine be destroyed?

A: Yes, but it is not easy. If you pour muriatic acid on the floor, it will etch. Strong acids will destroy the shine. Etched areas are easily repaired…we can show you how to do it yourself.

Q: At what stage of the construction process should it be done?
A: It depends. Edgework costs money. Sometimes it pays to do 6 of the 8 steps before the “build out” and then do the final 2 steps just before completion. Edgework controls the timing of our service.

Q: Is it good in schools?
A: It’s the perfect solution. It’s beautiful yet it’s durable and easily maintained.

Q: Where do you not recommend it in a school?
A: Offices and music rooms because of acoustics, and bathrooms because of the potential of urine etching.

Q: If a re-polish is needed in 5 or 10 years, what is the cost?
A: Typically R60-00/m2

Q: Is it dusty or messy?
A: We run our machine “wet” makes the process almost dust free, but we have the waste to remove of site.

Q: What’s the #1 reason people polish concrete?
A: Residential…for its beauty.
Commercial & Retail…for its trendy upscale look.
Institutional…for its reduced maintenance.
Green Construction…because it is eco-friendly.

Q: Are all concrete polishers the same?
A: Absolutely not. If corners are cut, your floor will not look good 5 to 10 years from now. “Fly by Nights” are entering this business every day and damaging the industry by taking shortcuts and delivering disappointment.

Q: Can rain-damaged or carbonated concrete be polished?
A: Yes

Q: Do you apply a sealer?
A: No and Yes. We don’t apply an encapsulating sealer but we do apply a hardener that stops concrete dusting and helps the floor shine last longer.

Q: Are concrete floors cold and damp?

A: Concrete floors appear no more cold than ceramic or porcelain tiles. In winter concrete has the ability to absorb solar radiation coming in through the windows and thereby warm the air in the house. In summer concrete floors keep the house cool therefore producing a saving in the use of air conditioning.

 

Q: Are concrete floors pet friendly?

A: Yes, concrete floors resist pet stains and odours. They are easy to clean and scratch resistant. Contrary to synthetic carpets, floors or coatings concrete is non-toxic and does not release harmful VOCs

 

Q: Can concrete floors be heated?
A: If the climate requires it under floor heating systems can be installed under the concrete. Concrete’s heat absorption allows the floor to retain heat and stay warm long after the heating has been turned off resulting in savings in electricity.

 

Q: How do concrete floors perform in medical facilities and hospitals?
A: Concrete floors are ideal for these types of facilities due to their high resistance to abrasion and chemicals and low maintenance. They are perfect for labs, pharmacies and other areas requiring an easy to clean and maintain surface.

Q: Do concrete floors crack?

A: Yes, Expansion joins and strips are used to minimize the chance of cracks appearing through the concrete. Recommended size of panels will vary slightly depending on the shape and size of the room but most commonly the floor should be divided into sections of +/-4sqm @ a 100m thick. Some people also find slight hairline cracks attractive as it adds to the rustic look of the floor and gives it that unique “handmade” feel. If the cracks are severe special fillers can be used to make them less noticeable.

Q: What about colours?

A: The concrete itself can be tinted to a variety of colours. Different types of aggregates available in a multitude of sizes and colours provide a wide pallette of concrete/aggregate combinations to choose from. You can easily find the right combination to best fit the style and look of your home. Using a natural concrete colour coupled with aggregates of similar hue can also create a very “industrial” look if desired. Concrete is also a natural “live” product which when mixed and placed will always create a difference in aggregate concentration and dispersion as well as differences in colors.

Q: What is the impact on the environment when manufacturing/placing concrete floors?

A: Concrete is made from natural materials and in some cases from recycled products. It’s made locally thereby reducing transport times and fuel consumption. Its manufacturing creates jobs and gives a boost to local economies as opposed to imported tiles and other types of coatings made outside the country.

Q: What concrete finish works best in driveways?

A: CGS XP is a process by which a thin layer of concrete is removed from the top of the surface thereby exposing the stones added to the floor mix. Theses aggregates provide excellent grip even on steep driveways making them safe to use in any weather conditions. When applied and sealed by an experienced contractor concrete driveways can last for many years without suffering the buckling, cracking and breaking typical of asphalt of pavers.

Concrete requirements and polishing procedures;

Please note that the concrete needs to pass strength test before the polishing stages can proceed.

There are two tests which we use.

Using a schmidt hammer: http://en.wikipedia.org/wiki/Schmidt_hammer

This will give us an indication on the compression strength of the concrete with out damaging the concrete. The concrete should have a strength of 25Mpa or higher.

The second test is a pull test:

http://en.wikipedia.org/wiki/Pull_off_test

This test needs a minimum of 2Mpa or higher.

Please note:The higher the results in the above testing will in turn provide a stronger and superior finish. Polishing concrete that does not pass the test can be done but you don’t get a smooth shiny surface and there will be additional charges as the wear on the diamond pads dramatically increase.

Polishing procedures

Polishing Process
The process begins with the use of coarse diamond segments bonded in a metallic matrix. These segments are coarse enough to remove minor pits, blemishes, stains, or light coatings from the floor in preparation for final smoothing. Depending on the condition of the concrete, this initial rough grinding is generally a three- to four-step process.

The next steps involve fine grinding of the concrete surface using diamond abrasives embedded in a plastic or resin matrix. Crews use ever-finer grits of polishing disks (a process called lapping) until the floor has the desired sheen. For an extremely high-gloss finish, a final grit of 1500 or finer may be used. Experienced polishing crews know when to switch to the next-finer grit by observing the floor surface and the amount of material being removed.

During the polishing process an internal impregnating sealer is applied. The sealer sinks into the concrete and is invisible to the naked eye. It not only protects the concrete from the inside out, it also hardens and densifies the concrete. This eliminates the need for a topical coating, which reduces maintenance significantly (versus if you had a coating on it). Some contractors spread a commercial polishing compound onto the surface during the final polishing step, to give the floor a bit more sheen. These compounds also help clean any residue remaining on the surface from the polishing process and leave a dirt-resistant finish.

You can polish concrete using wet or dry methods. Although each has its advantages, dry polishing is the method most commonly used in the industry today because it’s faster, more convenient, and environmentally friendly. Wet polishing uses water to cool the diamond abrasives and eliminate grinding dust. Because the water reduces friction and acts as a lubricant, it increases the life of the polishing abrasives. The chief disadvantage of this method is the cleanup. Wet polishing creates a tremendous amount of slurry that crews must collect and dispose of in an environmentally sound manner. With dry polishing, no water is required. Instead, the floor polisher is hooked up to a dust-containment system that vacuums up virtually all of the mess.

Many contractors use a combination of both the wet and dry polishing methods. Typically, dry polishing is used for the initial grinding steps, when more concrete is being removed. As the surface becomes smoother, and crews switch from the metal-bonded to the finer resin-bonded diamond abrasives, they generally change to wet polishing.

Step-by-Step:

  • Remove existing coatings (for thick coatings, use a 16- or 20-grit diamond abrasive or more aggressive tool specifically for coating removal)
  • Seal cracks and joints with a filler.
  • Grind with a 25- or 40-grit metal-bonded diamond.
  • Grind with an 80-grit metal-bonded diamond.
  • Grind with a 150-grit metal-bonded diamond.
  • Apply a chemical hardener to densify the concrete.
  • Polish with a 100- or 200-grit resin-bond diamond, or a combination of the two.
  • Polish with a 400-grit resin-bond diamond.
  • Polish with an 800-grit resin-bond diamond.
  • Finish with a 1500- or 3000-grit resin-bond diamond (depending on the desired sheen level).
  • Optional: Apply a stain guard to help protect the polished surface and make it easier to maintain.

Although polished concrete floors are extremely durable through the densifying and polishing process, they will eventually lose their beautiful shine if not properly maintained, especially if they are located in high-traffic commercial or retail facilities. The good news is that while polished concrete floors are not maintenance-free, they generally are easier to maintain than other types of decorative concrete floors, since they require no waxing or sealers.

Routine maintenance for polished floors consists of daily dust mopping to remove dirt and grime accumulation that can abrade the surface of polished concrete. Frequent wet mopping is also needed. Although only clean water can be used, you’ll have greater success using a floor cleaner to suspend the dirt particles so they can be more easily removed.

We recommend using only neutral-ph cleaners on polished concrete, since a cleaner that is too acidic or too alkaline will deteriorate the concrete and dull the shine of the floor. The correct type of floor pad also needs to be used to prevent concrete surface damage. We recommend using very soft pads on polished floors to clean the surface without scratching or etching.

The exact maintenance regimen needed and the frequency of cleaning is largely dictated by amount of traffic the floors receives. High-traffic areas will require more frequent cleaning.

Checklist for maintaining polished floors:

  • Dust mop the floor daily with a microfiber pad to keep dirt particles off the floor. Soils act as an abrasive and can ruin the clarity and shine of polished concrete.
  • If wet mopping the floor, always use clean water and clean mops. Use an automatic floor scrubber equipped with a non-abrasive pad to clean large square meterage areas. Mop and bucket cleaning can be used in smaller areas.
  • When wet mopping, use a neutral floor cleaner formulated to suspend the dirt particles so they can be more easily removed. Using water only leaves much of the dirt on the floor, where it will eventually abrade and discolor the surface.
  • Try to clean spills and stains from the floor as quickly as possible so they don’t absorb into the surface.
  • Give the cleaner enough time to start breaking down the grime, such grease and other contaminants, and then suspend the particles. If you apply a cleaning agent and then immediately vacuum it or mop it from the surface, the cleaner will not have sufficient time to work.
  • Make sure the cleaning solution does not dry on the surface. This can be accomplished by cleaning small areas and making sure the entire process is complete before moving on to other areas.