Cement Floor

[GregLaROCHE]

I’m finally getting a concrete pad poured as a floor for the cellar where I do my reloading and other gun related projects. No more searching for tiny screws, primers, etc. that have fallen on the gravel floor.

The contractor doing the work says today there is a machine with blades that spin and it will give a very smooth finish. So smooth that I won’t need to paint it. Is that true?

Maybe I’ll paint it anyway. What do I need to know about painting fresh cement today. Is there a minimum amount of time it has to cure? Does it need a treatment or primer? Can I get away with one coat of paint? I know epoxy based paint is probably the best, but I need to keep things within a budget. What other paints could work?

At last what color would be best? I thinking gray, but not sure if a lighter color to reflect light and make it easier to find small items that find their way to the floor, or a darker color not to show the dirt. Are there other colors or treatments/sealers, that make sense that I should consider?

I’ve waited years for this floor, so I want to do it right, but also as economical as possible. Thanks for all input and advice.

[Evoken]

If your finishers are good, then yes a "whirleybird" makes a very nice smooth finish.
If you want it super smooth and are planning on painting it tell him to burn it in, he will know what that means. Allow the concrete to cure for a MINIMUM of 27 days, longer if you can wait. That is what it takes to come up to strength and release most of the trapped water. I would also suggest putting in a vapor barrier under the slab, it will cost extra but will help the floor not sweat as much.
If I was going to paint a floor, i would use an epoxy paint. Any i have used do not need a primer coat. Spend the extra money on real epoxy, not water based. It is harder to work with and stinks during application but is much more durable. If you want it to last, use the good stuff. Sherwin Williams makes some of the best epoxy paints for industrial floors, they are expensive. I'm sure you know they old saying "buy once, cry once"
When i finished my basement i used water based epoxy because it was left over from the job i was on and was free. I'm glad i did not pay for it, it scratches fairly easy and I would not use it again.
If you don't need to brighten it up with paint, good old concrete sealer is just fine as well and most likely alot cheaper.

[William Yanda]

I do not have personal knowledge in this area. I have seen discussions of the subject on Garage Journal.com. Happy reading, there are a bunch of guys there with a lot of experience in that area with a similar atmosphere to what I have found here.
Regards.

[ascast]

I have a floor like that, smooth as glass. In certain situations it is a slick as dish soap on glass, I live in upstate NY. It gets cold and icey. best wishes

[NyFirefighter357]

I would have them add concrete pigment/dye to the mix as the colorant. Concrete needs a long time to cure at least 30 days before you paint it. If I were to "paint" it I would use a concrete stain over a paint or epoxy that seal the surface as concrete always draws moisture from below. This of course can be minimized by using plastic or rigid foam insulation underneath and good drainage. That trapped moisture will over time push the paint or epoxy surface up causing flaking/peeling or efflorescence. Stain allows the moisture to come through as does pigment/dye. I don't know this product it's more of an example. I know cement plants can get coloring in bulk bags. https://surecretedesign.com/product/fresh-concrete-color/

[Petrol & Powder]

Another vote for the epoxy type paints but I would wait for the concrete to completely cure (which is roughly 28 -30 days depending on who you talk to).

I used the two part epoxy on a car port at a former house and it was tough stuff.

If you can stay completely off that concrete while is cures, you'll reduce the chance of getting any oil or grease on it before painting, but this isn't always practical.

In an outdoor application some people like to add grit (sand) to the paint to get better traction. On an indoor application I would avoid using grit in the paint, I think the smooth finish is better, but that's me.

One advantage of the smooth finish is a squeegee can be used to push water off the floor. That can be handy if you have a drain and want to get water off the floor in a hurry.

You can dye the concrete as NyFirefighter357 suggests but the surface will remain somewhat porous. That is a good thing in terms of letting moisture out (as he correctly points out) but there will be a bit of concrete dust and the surface will be prone to stains from oil/grease/dirt, etc.
The clear concrete sealers will help to keep the dust down but they aren't nearly as durable as the epoxy finishes.

Also consider lighting and contrast. Finding a tiny spring or detent pin on a cream colored surface may be easier than finding the same item on a dark grey surface.

Good Luck

[frkelly74]

Vapor barrier under the slab, be sure there is one. We used 6 mill visqueen but I am sure there are more up to date materials available at a higher cost. Even I could finish concrete with a power trowel. make sure there is plenty of ventilation. Some of our guys got a good dose of CO poisoning once in an enclosed space running a power trowel.

[Petrol & Powder]

https://www.youtube.com/watch?v=7KvxOuC7Bhc

[Mk42gunner]

No experience with a power trowel, but I don't think you want a floor finish that is very slick. You still need to be able to sweep it and maybe swab it clean, but slick concrete with a teeny tiny bit of moisture makes for lots of slips and falls.

By the way my experience with slick concrete mostly comes from the Greenhouse, what used to be the US Navy Gun School in Great Lakes, where we actually waxed bare concrete. Yeah it didn't make any sense to me either.

Robert

[Plate plinker]

Power trowel. That is how we make floors super slick and flatter if you know how to use it properly.

[shell70634]

I had a new shop built 2 years ago. Had the floor finished smooth and I stained it myself with a cheap portable sprayer (like insecticide application) and concrete stain. It came out great. I had to wait 3 weeks after pouring and had to clean the floor really well. Throw a few dry leaves down while it's wet. Leaves a nice shadowy image. I put a sealer over the stain. Floor cleans easy and the mottled uneven color looks good.

[abunaitoo]

I'm probably wrong, but years ago, I thought there was something called "self leveling cement".
Is there such a thing????
I have an area that I've wanted to level the cement floor.
Never got around to it.

[John Wayne]

The NY firefighter and Shell have the solution I would use. If you ever have moisture come up you'll regret paint. But if you use paint, buy the paint used on aircraft hangar floors.

[trebor44]

Super smooth is super slick with very little moisture. Cement is meant to be porous. It does 'sweat' and it takes a lot longer to 'cure' than many realize or admit to. Epoxy it if you want but know that it will require careful selection of footwear. Epoxy with sand for traction has some real advantages! Or leave it semi-smooth and get horse trailer mat for comfort.

[Der Gebirgsjager]

Been there and done that. Yes, the blades will give a smooth finish. What kind of surface is the concrete being put onto? If it is dirt, then you'd be wise to put in a moisture barrier and pour it at least 4 inches thick. You would also do well to use rebar installed in a grid pattern to prevent cracking as the concrete dries and shrinks. You'll still be looking for the tiny screws and dropped parts, as that is one of the laws of the universe, but the situation will change from "gone forever" to "might find someday". ;-)

[GregLaROCHE]

Is there a type of sealer I can use that I don’t have to wait very long after the concrete is set to apply it. Say four or five days later.

[Kraschenbirn]

Floor of my workshop/reloading area has a 'troweled' finish and, rather than mess with paint/stain/expoxy, I laid Harbor Freight anti-fatigue mats over the whole surface. No waiting for epoxy cure, no 'slippery when wet', no staining from spills! First set of mats lasted eight years; just pulled those up and laid new mats last winter.

Bill

[GregLaROCHE]

I'm probably wrong, but years ago, I thought there was something called "self leveling cement".
Is there such a thing????
I have an area that I've wanted to level the cement floor.
Never got around to it.

There is such a product and I’ve used it. You can level 1/4-3/8”with the product I used. It’s not meant to be a hard surface you walk on. It is designed to level a floor before putting down tile or other floor coverings.

[GregLaROCHE]

Floor of my workshop/reloading area has a 'troweled' finish and, rather than mess with paint/stain/expoxy, I laid Harbor Freight anti-fatigue mats over the whole surface. No waiting for epoxy cure, no 'slippery when wet', no staining from spills! First set of mats lasted eight years; just pulled those up and laid new mats last winter.

Bill

I’ve wondered if linoleum is still used these days. Probably more effort than I am ready to put in. I’m hoping there’s something simple I can just paint or spray on. I’m not so worried about color as something to seal it if for example used motor oil gets spilled on it. I tinker with more than reloading in my shop.

[Der Gebirgsjager]

Is there a type of sealer I can use that I don’t have to wait very long after the concrete is set to apply it. Say four or five days later.

There are sealers, but it is far better to lay down a "membrane" on the dirt. There are several types, but most of them are a thick plastic type sheeting that prevents the ground moisture from migrating upward into the concrete. Well worth the effort and expenditure.

DG

[GregLaROCHE]

There are sealers, but it is far better to lay down a "membrane" on the dirt. There are several types, but most of them are a thick plastic type sheeting that prevents the ground moisture from migrating upward into the concrete. Well worth the effort and expenditure.

DG

There is already a plastic membrane in place. Thankfully the forum advised it or the contractor was not going to use one. He said the concrete takes longer to dry with one. BS? I thought concrete wasn’t supposed to dry too fast, that’s why sometimes they have to spray water on it.

[BamaNapper]

I work with simulators, think 'robotic' type hydraulic equipment. Our facilities use epoxy paint for the floors. We use the water-based epoxies with no problem and they hold up well to fork lifts, pallet jacks, hydraulic spills, and a fair amount of foot traffic. For a recent job I did my homework to spec the paint and we went water-based even though cost was not a factor. Concerning water-based vs solvent based:


In the past, solvent is the favored carrier agent used for epoxy coatings because of the following reasons:
It can be used even in high humidity and cool temperatures.
It can bear petroleum contaminates in concrete floors.
It produces a much glossier surface.
It is more durable than water-based epoxy systems.

However, solvent-based epoxy contains high content of volatile organic compounds. As such, solvent-based epoxy cannot be used indoors because of the harmful fumes. When used outdoors, you will have to utilize proper respirators and avoid open flames like furnaces and water heaters because the solvent-based epoxy is highly flammable.

If you are looking for solvent-based epoxies, you may have a hard time finding them as some states have banned their use if unless they are produced with low VOCs. They are being used less and less nowadays.

I would not hesitate to use one of the water-based epoxies.

[Elmer Fudd]

I strongly recommend placing at least 4" of fill material over your vapor barrier. This gives a buffer for moisture to migrate out of the concrete and then back in/through the new slab. Nearly every slab I have seen with joints cut in it curls, meaning it isn't flat in the last few inches on both sides of the cut, but sloped up.

Your coating instructions will recommend a cure time - follow those instructions. Concrete has lots of water in it, some is hydrated with the cement, some evaporates or migrates down (if you give it a place to go). Better put, the water needs a place to go. Sealing it below and above will cause problems you don't want to rectify.

[Gtrubicon]

Elmer Fudd is correct, I would broom finish it, my garage floor is so slick I have fallen with wet shoes, and I’m only 44.

[Plate plinker]

Is there a type of sealer I can use that I don’t have to wait very long after the concrete is set to apply it. Say four or five days later.

You can seal it same day right after its finished.

[Plate plinker]

There is already a plastic membrane in place. Thankfully the forum advised it or the contractor was not going to use one. He said the concrete takes longer to dry with one. BS? I thought concrete wasn’t supposed to dry too fast, that’s why sometimes they have to spray water on it.

don't know where you reside but here in the fall and cooler months we use mid range water reducer and non chloride (polarset) accelerator to kick it into high gear so we are not camped out on a job for 6-7 hours. I want 3-4 hours and out.

[abunaitoo]

There is such a product and I’ve used it. You can level 1/4-3/8”with the product I used. It’s not meant to be a hard surface you walk on. It is designed to level a floor before putting down tile or other floor coverings.

Thanks
From what I remember of the floor, it will not work.
Way over 3/8 uneven.

[samari46]

Greg, Where are you located?. Do you experience heavy rains or even flooding where you live?. And where is your house located in reference to others in your neighbor hood?. Since you have an unfinished floor in the basement you could have ground water coming up even though you may not be aware of it. This would happen if your house is lower than let's say your neighbor's house. I actually had to put in myself a couple drains from the casement windows to lead the water away from the house into gravel beds I put in to give the water someplace to go. Moisture barrier is definitely a plus. Fresh poured concrete should be left for 27-28 days to completely cure or hydrate. Staining concrete can be down while it's mixing in the concrete truck. All sorts of different colors. Or if you prefer can be done while it's drying. The rotary trowels do a nice job leveling and giving a smooth surface. Not up on surface finishes so cannot help you there. And before I forget a 6mil thick moisture barrier or thicker is definitely called for. 4" thick poured concrete is almost a minimum thickness in many parts of the country. Visqueen is a common brand of sheet plastic and sold in huge rolls. If at all possible should be done so that it's all one sheet and no seams or taped joints. And it should be extended above whatever thickness concrete you have poured. After the concrete is cured than you can trim it. One last thing in closing. is the existing gravel or dirt floor even all the way front to back and side to side?. If not then it will have to be dug up and leveled prior to pouring to assure an even concrete pour. Remember the 4" i mentioned before?. Otherwise you could end up with let's say 3" in one area and possibly more in others. Best to do this before any concrete is poured. Don't ask how I know this. Frank

[David2011]

My shop was just built over the past couple of months. I insisted on a slick floor because I wanted it to be easy to sweep. I’ll be doing wood working and building large RC airplanes so there will be lots of saw and sanding dust. I acid etched the slab and sealed it with Eagle Gloss Coat Clear Wet Look Solvent-Based Acrylic Sealer. Home Depot carries it. It requires xylene, acetone or lacquer thinner for cleanup so good ventilation is a must.

I put down two coats with a roller, giving plenty of drying time between coats. I’m going to try burnishing ir with a floor polisher and rolling another coat because I got some edge marks from the roller. The product is resolvent (dissolves into previous coats) so it’s easily recoated. Sweeping with a soft broom makes cleaning up after making lots of sawdust easy. The finish retains the wet look permanently. Even though it’s only been down for a few weeks I’m very pleased with it.

[GregLaROCHE]

You can seal it same day right after its finished.

What type of sealer are you referring to?

[ascast]

There is already a plastic membrane in place. Thankfully the forum advised it or the contractor was not going to use one. He said the concrete takes longer to dry with one. BS? I thought concrete wasn’t supposed to dry too fast, that’s why sometimes they have to spray water on it.

That is BS. Odd, I was thinking about how that opinion has changed over the past 50 years when I read that comment. Hard to believe any contractor today would not suggest an under moisture barrier.

[William Yanda]

"Another vote for the epoxy type paints but I would wait for the concrete to completely cure (which is roughly 28 -30 days depending on who you talk to)."

I have a vague memory of a formula something like "concrete achieves half of its ultimate strength in 4 weeks, and maxes out in 50 years"

Regards
Bill

[cwtebay]

I am a huge fan of putting the colour in the concrete rather than painting. It won't affect water coming up, and the best part is that it's done when the concrete is done and you'll never have to do it again. As far as "too smooth" - yes it's a thing, but finding things like primers or little screws on it will be as difficult as your current gravel.
And yes, power trowels are amazing. Similar to sanding a hardwood floor though, the corners and tight edges won't be finished the same.

Sent from my Pixel 5 using Tapatalk

[engineer401]

I strongly recommend placing at least 4" of fill material over your vapor barrier. This gives a buffer for moisture to migrate out of the concrete and then back in/through the new slab. Nearly every slab I have seen with joints cut in it curls, meaning it isn't flat in the last few inches on both sides of the cut, but sloped up.

Your coating instructions will recommend a cure time - follow those instructions. Concrete has lots of water in it, some is hydrated with the cement, some evaporates or migrates down (if you give it a place to go). Better put, the water needs a place to go. Sealing it below and above will cause problems you don't want to rectify.

Exactly. You can also purchase cans that will absorb humidity so you can have a more accurate estimate of moisture in the concrete before you place sealers or flooring on it. It's been awhile since I needed any of these but they can be found in an internet search.

[GregLaROCHE]

I’m starting to wonder about the the guy doing the work. He’s not a professional mason, more a guy that does a bit of everything. He has done a number of pads for people I know and I haven’t heard any complaints.

What I am starting to wonder about is the need for stress cracks or whatever they are called. The lines you often see in concrete. How necessary are they? I don’t think he is planning on any. It’s 12’x20’. There is a reinforcing bar(grid) of 8-10” squares about 1/8-1/4”. No fibers planned. It should be a minimum of 4” thick. The aggregate is the smallest used for concrete. Max size stones around 1/2”. He says it’s better for a smooth surface with smaller aggregate. It will all be mixed by an electric cement mixer. There is no access for a cement truck.

All advice appreciated. I’m starting to worry about this guy.

[engineer401]

The largest problem I've had with concrete is some of the contractors like to add a lot of water to the mix. It makes it easier to work with but it also makes the concrete softer and less durable. This is especially a problem in northern climates with freeze-thaw cycles for exterior work. Yours sounds interior use therefore, climate controlled. This is a good thing. I'm not sure why there is no access for a concrete truck. There are concrete pumping companies, shuttles that can be rented to carry the concrete from a truck to the site. A lot of friends with wheel barrows may work. I'm not really sure of your situation and what is available to you. It almost sounds like he's planning to use sacked concrete like that from the hardware store. You may want to get more detail from him and possibly more bids.

Control joints are needed to allow for expansion and contraction. a four-inch slab requires a joint no more than ten feet spacing. Thicker concrete allows for greater spacing.

It seems he's proposing the use of wire grid. This works if it's properly placed in the slab. Often times it ends up at the bottom of the slab where is does no good. It's a secondary crack control that reduces smaller cracks. fiber does the same thing and is guaranteed to be in the concrete. All materials have their uses and limitations.

It sounds like you have a lot of questions. Do you have an engineering friend or relative you can talk to? If so, see if you can get some free advice. Construction techniques can vary depending upon location, product availability and climate.

[slim1836]

Rule of thumb on sawcut joint spacing is twice the thickness. For example, if it's a 4" slab then every 8' is sufficient, 5" would be 10' spacing, etc...

Sawcut depth would be 1/4 the slab thickness. Keep in mind that the sawcuts should be filled to prevent moisture from coming up from below. Silicone works best as opposed to hot tar. a foam backer rod can be used to lessen the amount of sealant used.

This is what I used for many years on roadway construction but I realize you are not paving a road. Either way, you are just trying to control where cracking would occur, after all, all concrete cracks sometime.

There are lots of epoxy paints on the market that have various grits in them for a texture if you so choose to go that way for surface finish.

Slim

[Scrounge]

If your finishers are good, then yes a "whirleybird" makes a very nice smooth finish.
If you want it super smooth and are planning on painting it tell him to burn it in, he will know what that means. Allow the concrete to cure for a MINIMUM of 27 days, longer if you can wait. That is what it takes to come up to strength and release most of the trapped water. I would also suggest putting in a vapor barrier under the slab, it will cost extra but will help the floor not sweat as much.
If I was going to paint a floor, i would use an epoxy paint. Any i have used do not need a primer coat. Spend the extra money on real epoxy, not water based. It is harder to work with and stinks during application but is much more durable. If you want it to last, use the good stuff. Sherwin Williams makes some of the best epoxy paints for industrial floors, they are expensive. I'm sure you know they old saying "buy once, cry once"
When i finished my basement i used water based epoxy because it was left over from the job i was on and was free. I'm glad i did not pay for it, it scratches fairly easy and I would not use it again.
If you don't need to brighten it up with paint, good old concrete sealer is just fine as well and most likely alot cheaper.

I'm with Evoken on this, use the good epoxy from Sherwin Williams. My former employer had to do their floors three times in the nearly 8 years I worked there. Big industrial laundry, LOTS of traffic, heavy loads on marginal wheels, spilled chemicals, dirt, and grunge ground in. I'd go with a light gray, it will be some easier to find parts on. Or you could do a nice Safety Red. ;) Enough to do our plant, including the red safety areas, was about $4K a couple years or so ago. I'm thinking around 45,000 square feet. With the kind of loads and such we put over it, it's good for a couple of years with a bit of touch-up, or about 3 years and then it really needs a complete cleaning and re-coating. Even if you have a giant house, your basement won't be that bad. The Armorseal 650 that I think is what we used is about $262/gallon, covers 50-160sqft per gallon. A three-gallon bucket is about $900. Takes about 24 hours to harden properly. Ain't cheap, but you are unlikely to need to do it again in your lifetime.

[Scrounge]

If you get 80lb bags of concrete, you need about 40 bags for a 12'x20'x4" slab per the Home Depot website. The high strength concrete I'd want is sold in 50lb bags, so you'd need closer to 65 bags. $5.25 a bag when I looked at them just now. $341.25 without the taxes. He's gonna be busy as a one-legged man in a butt-kicking contest. And none of that includes allowance for mishaps, and Mr. Murphy paying a visit. My paranoia and home improvement experience says add about 10% more of everything. I'm no professional mason either. I just have a fairly good library, and a bump of curiosity. Last time I did any concrete work I think I was helping my grandpa, and he passed in 1977, so it's been quite a while ago. (Yes, helping. That's what I'm gonna call it. :) Concrete wire panels are 3.5'x7', so you're gonna need about 23 of them. Plus "wire chairs" to hold them off the bottom, and the panels are about $10 each. I have no idea how many of the "chairs" you'd need, but they range from $0.75/each to about $30 each, depending on how fancy you want to go. At least you'll only need a gallon of the epoxy. Check out the Home Depot site for prices and such.

[SweetMk]

I had my shop floor (over 2,000 square feet) poured in 1999.
(we used 4" tall house numbers to emboss 1 - 9 - 9 - 9 into the corner so I would know when it was poured,, I only needed to buy a one, and a nine,, am I cheap or what!! :mrgreen:)
If you pour this year, you would only need to buy a two and a zero house number to emboss the year,, wait two months, you will need to buy a one also,,

Anyways, when they poured it, the finisher guy said to go to a building supply in town, and buy several 5 gallon buckets of some sealer,,
I was to spray it on with a garden sprayer,,

Well, I bought the buckets, and the new garden sprayer,, and I sprayed it the way they told me to,,
When I was doing it, I thought, "What a waste!! This looks like I am spraying water on!"
the product was water thin, and clear.

Well, here it is, over 20 years later, the shop has had HARD use,, and still I get zero concrete dust.

There is only one way I can tell the sealer is there rather than bare concrete,,
if I spray some brake cleaner,, and the overspray hits the floor, it will soften the sealer, and for an hour, the spot will be "sticky"
but, then the spot hardens up, just as it was before.
I have spilled gas and diesel on the floor, only the brake cleaner seems to soften the coating.

I still have the partial bucket of the product,, stored in the shed,,, somewhere,,

[GregLaROCHE]

I’d like to know the name of that product and what type of base it has.

[Evoken]

A few more thing, and like others this us what I do for a living.
Control joints are necessary, the question is not "if" the concrete will crack it is "where" it will crack. You can almost not stop it from cracking. At 12'x20' I would do at least 2 down each center, 1/4" deep.
Mesh is fine for an interior floor as long as it is suspended in the slap. They sell products called chairs for this, they come in various heights and keep the mesh off the ground. They are 4' pieces of heavy gauge wire formed to look like a triangle when looked at on end. I would recommend 1" tall. This will place the mesh below center thickness and you wont have to worry about any poking out.
Seal the control joints with sikaflex, it is made for concrete. I believe you can get it at home Depot, lowes, etc. We use it in sausage tubes, but I think you can get it in regular caulking tubes.
Your slab calls for 2.7 yards, while it is not economical to get a "short load" from a concrete company, I would do it. Bag mix sucks, I dont care what anyone says. There is to much inconsistency in it. Different lots, this bag gets to much water the next not enough, you get the idea.
Tell him to get a power buggy, if he's got power trowels he has access to a buggy.

[Plate plinker]

What type of sealer are you referring to?

TK (thats my favorite brand) its from Minnetonka minnesota. 5 gallons is about $125 here, unfortunately you only need like 1 gallon.
AS-1

cut depth 25% of slab thinkness
4" concrete the control joints are a max 10 feet. In your case I would do 72"X80" because its closest to actually square which is good and looks more square. I like squares.

As Evoken says the concrete should be from a plant not that crappy bag stuff and he should have a buggy to get it to the site or just wheelbarrow it in, after all 3 yards is nothing. Concrete should be placed as dry as possible within reason for better strength (water is the enemy) never let your concrete guy add water to the surface (EVER!) if they try that they have lost it because they are inept and well....... they can try again at their expense.
For myself I would pour on foam, that helps with sweating and add in floor pex heat pipes if at all possible (radiant in floor heat is so nice).
If the base is questionable 3/8" rebar in a 5' grid is what I would do.
Also I doubt he will use a trowler because its inside (CORRECT?) unless they have access to a electric machine. At that dimension I would just hand trowel it and be done a experienced finisher can handle that singlehandedly.
I have been in the concrete game almost 20 years now.

[Lloyd Smale]

little bit of advice. I went from a dirt floor to a new shop with a concrete floor. Figured id be in heaven because everything that fell of the dirt floor went into a black hole. Well i wanted my concrete to look good so i expoy painted it. Dont make my mistake and use those color flecks that come with it. They make it just as hard to find dropped small parts as dirt is.

[slim1836]

Also, he should vibrate the concrete for consolidation of the aggregate. A jitterbug (old school) can be used in lieu of a vibrator and works well for small projects. Vibrate just enough for moisture to come to the surface and move to the next area. The moisture helps in finishing the surface. Over vibration will segregate the aggregate causing the larger rocks to sink and finer rocks to come to the surface. Do not over vibrate.

As previously stated, water is you enemy. You do not want self leveling concrete, easy to work with but weakens the concrete. Once the water has left the concrete (evaporates) the concrete has achieved it's strength, so the longer it cures the harder it gets. Once the surface has gotten hard enough to walk on you can put plastic on the top of the slab to retain moisture which will aid in keeping the moisture in which will increase the strength of the slab.

Slim

[gwpercle]

I hope the contractor put down a vapor barrier , in Louisiana we use Visqueen Membrane . under the slab between the dirt or fill sand . This keeps ground moisture from passing from the ground into the and through the slab onto the floor . A smooth finished concrete floor when it gets damp from ground moisture get icy slippery . You want a little texture to the concrete floor . Many good masonry paint/sealants ... some are made for commercial Kitchens , epoxy and slip resistant because kitchens tend to have wet floors and a lot of people traffic .
The most important thing is the ground vapor barrier ... the basement will have rusting problems without it ... at least in Louisiana it will !
Gary

[wmitty]

Suggest finding a contractor who actually understands Portland cement concrete and the importance of water/cement ratio and use of admixtures in obtaining desired results.