Concrete Flooring Came Out Mottled

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User offline. Last seen 2 years 33 weeks ago.

Hello - I am hoping someone could offer a suggestion for an issue that came up when I had a concrete floor refinished.  I am a designer and asked a crew to remove old laminate tile, clean the concrete floor exposed, do painted designs and then seal the flooring.  They did as I asked but the floor came out very mottled.  I do want it to have a used, industrial look so some mottling is expected but this seems excessive.  I am wondering if perhaps they didn't clean it enough - they said they scraped it, lightly sanded it, and washed it with water.  Do you think a good chemical cleaner would have helped?  Or should I try a lightly tinted stain to even out the color?  My concern with that is how many samples will I have to do to find the one I want and will it translate to more floors I am doing like this?  Does any one have a suggestion to keep the mottled look to a minimum without losing the used look?  I hope I am not asking too much.

Lindy A.
User offline. Last seen 4 hours 35 min ago.
Am I understanding the

Am I understanding the surface in the photo represents the end result of their cleaning, sanding, coloring, and sealing? This is totally unacceptible IMO. 


You referred to using a paint to achieve colored designs; but, this appears to be more of a concrete dye that was applied over a concrete substrate that was not property cleaned, prepared, profiled, or perhaps even a candidate for what you wanted done. 


So long as professional care is exercised, the concrete floor could have been mechanically grinder to achieve a uniform surface that could be dyed or stained to achieve appealing end results, lasting bond of protective sealer applied over them, and desired degree of longevity/performance/beauty.  IMO (based on 30+ years experience) painting concrete (whether indoors or outdoors) is doomed to a short life to begin with, will wear off quickly,  and is never a good  value; furthermore, paints are by nature topical and doomed to peals/flakes/blisters; resulting in an appearance much like your photo over a very short period of time. 


If you want a solid/uniform color (instead of a translucent or moddeled stain or dye look) then the surface needs to be cleaned, mechanically ground to create acceptible profile in order to assure lasting bond, then a 100% solids Industrial Flooring Epoxy (high build, green safe, solvent free, formulation) should be specified for appliation over the concrete substrate (vailable in a great number of factory colors and/or limitless custom ones that are not translucent or mottled.  Another option would be a fully pigmented Polyaspartic Aliphatic Polyurea (PAP) that is far exceeds the wear/abrasion resistance of a 100% solids Industria Epoxy. 


Please not that not every concrete slab is a canidate for direct application of stains, dyes, coatings, etc (perhaps it has deep gouges, holes with tack strips were removed, ghost images of VCT tile, marks left from other trades or foreign matter staining that could not be removed, pop outs of concrete, spalling, or other defects) ... in such cases the substrate could be thoroughly cleaned of all foreign matter, mechanically profiled, followed by (on interior surfaces) a polymer modified cementitious self-leveling micro-topping (thin, self-leveling); thus, creating a uniform colored surface (much like a blank canvas would be to an artist) that can be stained/dyed/sealed; result being true freedom of design, texture, and color.  If the surface is an exterior one, a polymer modified cementitious overlayment could be applied (again, providing you with a ways/means to achieve a new/uniform substrate ideal for various forms/types of decorative adornment that will increase curb appeal and value of the property.


Lindy A.

User offline. Last seen 2 years 32 weeks ago.
From looking at the picture I

From looking at the picture I see the white lines and numbers that were painted on there.The rest of floor is definately a result of the floor covering glue  and the effects of time.They probably cleaned the floor well enough but to achieve a more consistent look alot more of the surface would have to be removed.With that you risk exposing the aggregate in the concrete.