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Disclaimer:
Considering the multiple variations from the actual mix, region, finishing and curing methods then multiply this by design specifications.  Then you will agree that concrete is by characteristic artistic in nature, Hence it would be unrealistic to expect otherwise. Therefore Multi Polissage Montreal assumes that concrete was mixed, poured, placed and finished in accordance with standards set by the (ACI) American Concrete institute, (PCA) Portland Cement Association and the (CSA) Canadian Standards Association, as well as the (ASTM) American standards for testing materials. As stated above Multi Polissage Montreal shall not be held liable for circumstances that are beyond our control.

SAMPLES
The importance of a sample work can’t be overstated; as a policy we try to perform samples for each project we agree to. A sample will provide a fair reading for both the intended client and service provider. On occasions samples are just not possible due to schedules, locations and so on.... In such cases we need to work with reliable data and history to determine a reasonable reading. Furthermore a written acceptance form must be signed by architects, designer, owners and the General‘s implemented in such cases. Project will be delayed until final approval has been documented.

Gloss reading:
The combinations of floor flatness, smoothness and concrete treatment yield gloss unless intended otherwise. Because cement finishing has many variables, such as cement mixes, admixes, temperatures, and actual workers. A precise throughout uniform reading is usually impossible unless these factors are properly controlled before the fact and not after.

Uniformity Cream Polish:
Concrete finishing because of curing methods and troweling is never uniform in color or texture, therefore achieving uniformity after diamond polishing can be a very difficult challenge. Is there a solution? Yes! Cement finishing contractor should take measures to distribute curing compounds evenly. Power troweling should be equally burnished throughout; caution should be taken not to over burnish. It is worth noting that humidity can also contribute to different shades on concrete. A good advice on moisture issues is to take preventative measures. (always take this monster seriously)

Uniformity aggregate finishes:
Concrete is a mix of water, cement, and a mix of fine and coarse aggregates once concrete has been poured, floated and troweled, the control of uniformity has already expired. We recommend, should the client desire an "exposed aggregate finish", that proper vibrations is needed after the pour, and a broadcast of aggregates be added and spread evenly at the after screeding stage, this will ensure (but not guarantee) a better uniformity in exposed aggregates finishes. We also recommend that for the case of aggregate finishes, that concrete polishing should be performed before divisions are made.

Edge work:
In general edge work of concrete by default is usually rough and poorly troweled, if compared to main floor areas. We highly recommend that in accordance with the practice of concrete polishing that extra care be taken to prevent such defects. We also recommended that before any framework is done that the first few steps of polishing be performed. This method will yield a much better result at the end.

Cracks, pits, scaling, levels, stains:
Naturally we can't be held responsible for cracks, pits, scaling and levels of concrete or stains. These problems are usually directly related to the cement finishing, other sub-trades on premises or weather conditions can also contribute to damaged concrete.
Concrete treatment (Sodium silicate) or (Lithium)

It is highly recommended that each intended concrete to be polished be treated with a sodium silicate or Lithium, these penetrating sealing will seal the pores, density concrete and prevent dusting or contamination. These treatments have a minimum of life span of 10 years.

Stain Proof:
There are some products that will act as good stain retardants, however no perfect product has been developed as yet. The best remedy for stain proofing is to avoid spills that are below 5 and above 9 on the PH reading. Proper maintenance practices should be incorporated and spills wiped up as soon as possible.

Efflorescence:
Is a natural occurrence in concrete, the question is how to control it? During hydration the mix of water, humidity and cement all contribute to the natural occurrence of efflorescence. The solution to the removal of this white powder substance from appearing on surface is simply by treating or sealing the concrete after 28 days or 7 days for fast curing concrete.

Humidity:
An estimation of 33% water is sufficient for a normal mix (cement water ratio) however as is know in the cement finishing industry each pour has it's unique challenge. A 4% amount of humidity is considered low enough for most of the flooring industry, humidity should not be taken
lightly. Failure to take corrective measures at the start can lead to devastating results. We therefore recommend that either a calcium chloride test be performed or we prefer a RH (relative humidity) reading be taken before any services are performed on concrete.

Alkali silica reactivity: (ASR)
The cement finisher should thoroughly clean the mix of aggregates and use clean water. This will decrease the chances of contamination.

TIPS FOR FRESHLY POURED CONCRETE (for floors that will be polished)
Suggestions for freshly poured concrete (soft) concrete

1) Concrete must be Portland cement and meet ASTM C150 (CSA362)
2) Freshly poured concrete must be cured for at least 28 days and have a minimum PSI of 4000.
3) Burlaps or curing compound that are water based will facilitate the intended polishing procedures
4) Metal fibers should be avoided and if necessary can be replaced with plastic fibres. Metal can distort the
finished product and are visible to the naked eye.
5) Concrete finishing should include strike-off, bull floating followed by steel troweling.
6) Concrete overlays should be at least 2 inches thick (200mils) with a preferred mix of fine aggregates.
Micro topping should be minimum one quarter inch (25 mils)
7) admixtures will not effect the polished floors, however air entrapment can cause miniatures air holes in
concrete surface.