Appreciate the info.

Good explanation. I'm interested in a base gray (single color) polished floor for a new home build. Since I know this ahead of time, what advice do you have to help reduce costs? i.e. what decisions - and with who - can be made up front prior to home construction? TIA

You have to let the concrete PEOPLE know what you have in mind for flooring. You have to tell the BUILDER what you have in mind for flooring. You then have to bring in epoxy/concrete flooring SPECIALISTS to consult with the people who are pouring the slab so that the RIGHT things are done BEFORE the "expensive" epoxy people get on the job site.

That has to be done before the slab is poured. Once it is poured, it is the same process as everyone else. If your slab is poured, then you are already too late to "prepare" for the final concrete finish.

No matter what point of the build you are in, make sure you get the epoxy/concrete flooring specialists involved as soon as possible. They can advise the GC on how to go about the build to keep their work/prep to a minimum.

I'm going to finish the concrete flooring in my basement (house is 3 years old). The original plan was to layer flooring on top, but now I want that industrial polished concrete look. The look I am going for is the polished, aggregate look. Does polished concrete look shiny without a seal on it? The concrete guy said since we do not know what color, size or depth the aggregate is at so I need to pay $2000 for a test area. He also says I need to pay $1150 to bridge the 2 control joints (joints need to have stain/dye/sealer/epoxy per him). Does this sound right? Am I right in thinking polished concrete is the lowest maintenance, lowest wear? I want the concrete to be darker than the light gray it is right now, do I need to go and stain it after the polishing?

What do you mean by "aggregate"? Are you talking about the microtopping (the high-quality concrete that is designed to be "finished flooring") or are you talking about a textured finish with different sized rocks in it that will be polished down (terrazzo floors have this look)? These are two different beasts with two different price tags.

If you want a darker gray, you will probably have to stain it or have a coloured mix added. Polished concrete can be shiny, satin or even super gloss. It depends on what you order and how much you want to pay for it. The sealant can add gloss, or it doesn't have to.

Unsealed concrete will stain and etch. Kinda like marble stains and etches. Some polished concrete require WAX or POLISH!!!! Yah! Like 2 per year for 5 years...then you chemically strip them down (remove all that polish you slathered on) and then start again...until you cover the floor with something else.

Control joints are funky. I'm not knowledgeable enough to deal with that. You can ask your questions on www.thefloorpro.com There are a couple of concrete/epoxy guys over there that REALLY know there stuff and will offer "concrete" answers inside of a day or two.

Total costs = it depends, it depends, and it depends. And right after that, it depends on where you live.

True polished concrete floors do not have a topical sealer applied. Meaning, the shine is mostly achieved by the refinement of the concrete with a series of diamond abrasives. The final step is to apply a micro sealer that gets buffed in. This sealer will not peel like a topical sealer can.

There are basically 3 stages in the process.

Grinding is the first step and the most aggressive. This is where aggregate is exposed (what Katie is talking about). The aggregate exposure can either be minimal (small aggregate exposure) or large aggregate exposed. One point about aggregate exposure on an older residential floor is that it will usually not be uniform throughout the whole floor area. This is because residential homes where not built to have the concrete as the finished floor. Homes and commercial floors that are specified to have polished concrete floors are usually poured and finished in a way that the aggregate under the cream (top) layer is in about the same depth. Also, large aggregate exposure may not be attainable in a basement. The concrete grinding machines that do the heavy grinding required are in the 1,200 pound range and will not be able to bring up and down the stairs.

A densifier is usually applied after the grinding stage. This step makes the top surface of the concrete more dense which will allow for a better polish on subsequent steps.

Second and third step is honing and polishing. These steps further refine the concrete with progressively finer grit diamond abrasives.

As for the color, the polishing process will darken the concrete significantly. The micro sealer will darken the floor further. However, if you want the gray even darker, it can be stained in the final stages of the process with a dark gray stain.

True polished concrete is very easy to clean. Attention should be paid to cleaning up spills as soon as possible though because it will stain if left unattended.

Albert Lazo (owner)
Love Your Floors
www.stoneandconcretepolishing.com