Creating Nice Concrete Floors. Nice basic concrete floor in a house in Sun Valley, Idaho. Achieving Desired Color. The natural color of most concrete is light gray. This is because most portland cement is very gray, and most gravel and sand is gray enough. Though often overlooked, your garage is one of the most important rooms in the house. Its also one of the largest. It gets used several times everyday. It acts as. These are my notes on creating nice residential concrete floors. In my primary residence, I put in about 1. I used a 6 inch slab on crushed stone with 12 inch PEX tubing for hydronic heating. Im pretty happy with these floors, although not wild about the results I got in finishingsealing them. I am in the process of building a second home in which all three levels will have concrete floors. In principle concrete is a very inexpensive, b a wonderful means of installing hydronic heating, and c attractive. Trowel the area with a steel finishing trowel when the patch material has become stiff. This will flatten and smooth the surface, and cause cement paste to rise to. The old garage was made for a lower vehicle than my present one. It was an experiment, using nyloncement nylon fishnet and cement to make a roof without using. Indooroutdoor stone and epoxy flooring systems for pool decks, patios, walkways, showrooms. Free estimates and samples. But, Ive found that there is all kinds of confusing information about how to achieve these aims. Here is what Ive learned based on experience, research, talking to concrete contractors, and my own experiments. Formulation. Concrete is formed by mixing water, portland cement, sand, and gravel. A chemical reaction occurs between the cement and the water that results in a rock like material with very high compressive strength. This material ends up in a mixture with sand and gravel, which forms a very strong, very inexpensive composite material. How strong It depends on the mix, but typically several thousand pounds per square inch compressive strength. Rat Fink Sans Font. In flooring applications, concrete is almost always reinforced with either wire mesh or rebar, which theoretically provides tensile strength as well. Concrete gets stronger with agefor decades. Old concrete is super strong stuff. The corollary is that if you want to cut or drill concrete, do it when it is young. There is something called lightweight concrete which entrains air in the mix. Its not that light. It also has risks of delamination of the top layer if steel troweled. How To Patch A Garage Cement Floor' title='How To Patch A Garage Cement Floor' />I wouldnt bother. Cost. Concrete is an inexpensive raw material. It is sold in units of a cubic yard usually just called a yard. A yard is a lot of concrete. A typical concrete truck holds 5 1. By definition, a yard of concrete is 3ft x 3ft x 3ft 2. So, a yard of concrete is equivalent to these floor areas 5. If your floor is 1. The material itself costs about 1. This is the price for a truck to deliver several yards to the site. Lets assume 1. 30yard. At that price, the raw material for your 1. The cost to place the concrete is about 1. Its about a third less for driveways, walks, etc. This includes getting the concrete from the truck to the floor, leveling it, and steel troweling it to form a smooth surface done several hours after the initial pour. Youll also pay about 7. The pump truck literally pumps the concrete through a large hose to the floor location. Finally, youll pay for the rebar or wire mesh that reinforces the floor. This will cost another 0. So, to get a smooth freshly poured concrete floor in place will cost about 2. All in, a 1. 00. 0 sq ft lower level floor with a 5inch slab will cost about 5. That same area with a 3 inch slab say on an upper level will cost about 4. Both scenarios include 1. This does not include placing any crushed stone under the slab, installing a vapor barrier, or installing insulation, as you will probably do for lower level slabs. It also does not include placing in the slab any plastic tubing for hydronic heating, which youll want to do if you live in a climate requiring heat. These prices are for Park City, Utah, a resort community outside of Salt Lake City. Prices are similar where I live outside of Philadelphia. Prices may be lower in some rural locations. Theyll be a lot higher in Manhattan. On a lower level which will have a slab poured anyway, a finished concrete floor is the cheapest floor you can do. On an upper level, there are less expensive options. Specifically, you can install decent carpet for less money, especially when you consider that the floor framing e. However, if you are certain you will use hydronic i. This is because the alternative ways to get plastic tubing under floors for hydronic heating are all about as expensive as just putting in a concrete floor. Cost can be a primarily motivation, but honestly, I just like the look and feel of warm gray concrete. It looks great with colorful rugs. It is a nice neutral background for almost any decorating style. It is really low maintenance to boot. It feels very nice in bare feet during heating season. Reinforcement. Some argue that rebar and wire mesh are equally effective in reinforcing concrete if properly installed e. Fine Homebuilding article Rebar vs. Welded Wire Mesh, 2. However, one respected contractor declared to me wire mesh does nothing. Ive demolished a few concrete floors for other projects, and have found the mesh at the bottom of the slab, nowhere near the center of the slab where it belongs. My opinion is that either mesh or rebar can work as reinforcement, but that wire mesh is more easily installed incorrectly, and so rebar is the safer method. I also believe that in most upper floor residential slab applications, it pretty much doesnt even matter if the concrete is reinforced. Generally, the structural engineer does not assume any strength or stiffness from the concrete floorits basically just a layer of concrete sitting on the subfloor. In my opinion, cracks will form no matter what you doso that isnt the issue. So, in sum, I would use rebar for slab on grade e. Slab thickness. In lower levels e. Mine will be 5 inches thick just because thats the minimum my flat work contractor recommends. When  you use concrete in an upper level you have to support it with the floor structure. Its heavy, about 4. So, you cant generally make it 5 inches thick. Probably the thinnest feasible slab is 1. Probably the thickest you would make it is 3 inches thick due to weight considerations. My brother, who is also an obsessive engineer, has determined that 2. My architects argue that 3 inches is the right thickness to minimize cracking. I doubt anyone has studied cracking as function of slab thickness in any controlled way, and I personally doubt it matters much on that dimension. Im going with 3 inches based on the preferences of the architect, the contractor, and to be absolutely sure Ive got plenty of coverage over the heating tubing. You also need to think about what happens at the edges of the floor. In general, you pour the floor after the walls have been framed, but before the drywall has been installed. You pour it right over the sub floor, usually oriented strand board OSB or plywood. In most cases you need to add additional  layers to the plate the 2 by lumber that supports your walls. This is because you need something to attach the bottom of the dry wall to after you pour the floor. So the wall plate has to stick up above the concrete at least an inch or so. So, if your slab is 1. In my case, since Im using a 3 inch slab, Im going to use a triple plate i. The slab will cover the first two, and the top one will be the nailer for the baseboard and dry wall. Note that the wall plate is super cheapdont worry about that. Protecting the Surface. In most residential construction, a concrete floor will be covered by carpet, tile, or wood. Thus, the trades usually make a mess of the floors without any concerns. Paint will splatter, drywall mud will cake surfaces, there will be chips and dings from dropped objects, etc. This is all bad if the concrete will be the finished floor. I spent a couple of days scraping and scrubbing with a scotchbrite pad on my first floor, and thus learned my lesson the hard way.