Pro Tip

The Difference Between Cement and Concrete

Many people use the words “cement” and “concrete” interchangeably. While they are related, Pros know they are two very different things. Whether you’re asked to explain the difference to someone else, or just want to make sure you’re using the correct term, here’s what you need to know.

What is Cement?

When most folks talk about “cement” they are usually and incorrectly referring to concrete. This includes things like referring to the “cement” sidewalk, or seeing a “cement” truck driving down the street. The confusion is understandable. It has been forced upon us by Hollywood and the media which clearly doesn’t know the difference. Do you remember Jethro Bodine and the Beverly Hillbillies? If so, you may recall that they didn’t have a swimming pool, they had a “ceeeeement pond.”

Here’s the difference. Cement is a powder that by itself would not work well for pouring a sidewalk or a swimming pool. It’s just one ingredient used in the recipe for concrete.

Cement comes in lots of different flavors but the overwhelming majority of cement is gray and is referred to as portland cement. For any grammarians that happen to be reading this you will notice the word “portland” is not capitalized. That is not a typo. Portland is an adjective that modifies the word cement, not a city. The name portland cement comes from the fact that its inventor (an Englishman in 1824) thought that the hardened product resembled the limestone quarried on the Isle of Portland in the English Channel.

How is Portland Cement Made?

In the interest of space and to avoid causing you to stop reading, I will greatly oversimplify this. Simply put, portland cement is made by combining limestone, sand, bauxite, gypsum and a whole host of other possible raw materials. The materials are heated until they all melt together and then are cooled. This cooled product is called clinker. The clinker is ground into a fine powder that we call portland cement. This process is actually quite fascinating but requires a chemistry degree to make sense.

What is Concrete?

Concrete is a combination of stone (rock, gravel), sand, portland cement and water, in descending order of the amount of each material in the mix. As with cement, a full discussion on all of the types of concrete would bore most to tears, so we will stick with the basic product most people are familiar with. A residential sidewalk is likely to have a compressive strength of about 3,500 psi (pounds per square inch). That is the load in pounds that it can handle. The strength of the mix is determined by the application. For instance, the concrete in a high-rise building may be 6,000 psi or higher.

The properties of concrete can be altered by adding other ingredients in specific proportions. You can make it set faster or you can add air to give extra protection from the damaging freeze/thaw cycles of winter. Many concretes contain recycled materials such as fly ash or slag. Fly ash is the airborne residue left from burning coal and slag is a by-product of blast furnaces used in the making of steel. Using these recycled products not only keeps millions of tons out of landfills but they can improve the performance characteristics of concrete.

Bottom line: Cement is a powdered ingredient used to make concrete. Concrete is the material used to make sidewalks, driveways and buildings.

Sakrete makes a number of different concrete formulations in varying strengths and set times to meet the needs of different job requirements.

Comments (24)

Kathleen Meredith says:

Greetings: I appreciate your explanation of the difference between these two words & two products: concrete & cement.

I have been making decorative stepping stones ( not really intended for anyone to step upon them) for my garden. The original kit had what I believe must have been portland cement; it had no stones mixed in the powder. I did not know what to buy to make more, using the same molds, so I bought a bag of concrete mix. It had too many stones, so I removed some of the larger ones so there was not so much competition at the top where I press shells, stones, glass & other decorative bits into the surface.

Do you recommend that I use reg Sakrete concrete mix, or would it be better to use portland cement? Thanks for any suggestions.

Kathleen

Sakrete says:

Kathleen, how thick are these stepping stones? You might consider using Sand Mix if they’re under 1.5″ deep – no stone in this mix, which would give you a really smooth finish.

Blayre Christian says:

Thanks for the information, I have a pro event coming up and I will certainly use some of this in my presentation

Walter Gilbert says:

I am planning on pouring a 16 inch sonotube 5 ft deep with bolts for a light pole. The maximizer bags seem to be the product to use but I am not certain. Can you advise the quantity of bags of maximizer if appropriate and where I can find it? I 20 minutes above Spartanburg SC. Thanks in advance.

Sakrete says:

Walter, Maximizer would be the way to go if you can get it! 7 bags of Maximizer vs. 12 of standard High-Strength.

Louise Riden says:

Is there any ingredient difference between the products in Sakrete High Strength concrete mix and high strength concrete mix delivered in a concrete truck

Thank you

Sakrete says:

Louise, that’s a loaded question, but in all important ways, no there isn’t much of a difference. They’re going to LOOK very different (bagged mix is significantly “drier” than ready mix), but ultimate strengths will be very similar, and therefore long-term performance will be almost identical.

Lee says:

If I frame up my foundation for a 20’x20’x4” shop floor,so how much concrete or how many yards?thank you for your time.God Bless. Lee Farmer.

Sakrete says:

Lee, that’s about 133 cubic feet, or just shy of 5 yards. Sounds like a ready mix truck is in your future…unless you really want to mix 300 60# bags!

Evan Thornton says:

Whoever wrote this should be given free rein to describe all aggregates, mixes, compounds, and chemical solutions.

*Very* on-point.

Sakrete says:

We do our best. Thanks, Evan!

Linda says:

I am one of those people who always said “cement truck”” and “cement sidewalk” Now I know that our driveway I recently crashed my knee into was concrete. I should know better. My mother worked for Portland Cement in Detroit in the early 40’s. Thanks for the info and good humor.

Sakrete says:

Rose, unfortunately there is no such thing as “no mix” concrete. No way around doing it the hard way!

Raymond says:

thank you for the definition

Rebecca Parsons says:

I filled some very small hairline cracks in the basement blocks and got a good bit of extra sakrete on my blocks. I have tried sanding it off but I am afraid it is going to look like I have big cracks in my wall. also i am planning on painting the blocks and am afraid that these big extra areas will show. how can i clean it off without damaging my blocks. Any advice will be appreciated. Thank you

Sakrete says:

Best bet would be to grind it off, but you could also try Concrete Dissolver…although that might be tricky considering you’re removing concrete from concrete!

Nola says:

Thank you!

Rich Riley says:

Great explanation!

Jack says:

How much does maximizer weigh per cubic foot after curing, excluding any reinforcement material (rebar).
Could you create a calculator to determine weight for both normal and maximizer after curing?

Sakrete says:

Maximizer (like all Lightweight concretes) is going to be about 115 lbs / cu.ft. vs. about 145 lbs / cu.ft for standard concrete.

Good idea to create a calculator for that! We’ll look into that.

steven says:

Is there a way to make a pizza oven using concrete

Sakrete says:

Absolutely, but you’re going to want to cover the interior of the oven with fire brick.

Elaine Fitzgerald says:

Will be filling in holes on bottom of front door cement stump. I have a 10 lb bag of Sakrete Crack Resistant Concrete Mix bought in 2012. Bag is stamped with manufactured date: 4/27/2012. Is this mix still good or should I throw out and buy new bag?

Sakrete says:

Elaine, that’s almost definitely going to be no good. We warranty our mixes for 12 months from the date of manufacture – would recommend getting some new material for this one!

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