Fast-Setting or Standard Concrete: How to Decide

Whether you’re setting a mailbox post or pouring a patio, how fast the concrete needs to set is a critical factor when buying concrete at a home center.  A bag of standard concrete and a bag of fast-setting concrete may look similar, but understanding the differences in how they work will help determine which mix is the best for your project.  Luckily, Home Improvement expert Danny Lipford breaks it down for you.

Fast-Setting Concrete

The best thing about Fast-Setting Concrete is how easy it is to use.  All you do is just add water — and it sets in 20 to 40 minutes. It’s the most efficient option for setting posts for things like mailboxes, fences and lamps. You just have to dig a hole for the post, pour in the dry mix and then soak with water. Best of all, you can hang fence and other heavy loads on a post set with fast-setting concrete in just four hours. But speed and ease doesn’t mean you sacrifice durability.  Fast-setting concrete is really strong, reaching 4000 psi — or pounds of force per square inch —after a month. That’s stronger than the concrete used for foundations on most homes.

Standard Concrete

Is also easy to use and can be mixed in a wheelbarrow or tub, or a mixing machine. Simply add 2.8 liters of fresh water to one 80-pound bag of Standard Concrete and mix thoroughly. Standard concrete is great for general work, but it’s especially effective for large projects over 2 inches thick — like patios, sidewalks curbs and steps. Standard concrete sets in 24 to 48 hours and curing takes about five days in warm weather (70 degrees Fahrenheit or higher) or seven days in colder weather (50 to 70 degrees Fahrenheit).  So that is one big thing about Standard Concrete – it  does require time to cure, so keep that in mind when making your decision. After curing, regular concrete also can withstand 4000 psi.

Remember: While the tendency is to use more water when mixing concrete to make it easier to pour and finish, the more water added to the mixture, the weaker the finished concrete will be. So it’s really important to follow the bag’s instructions to achieve the right balance.

Things to Consider

While you can use fast-setting concrete or standard concrete for many applications, some projects are better suited for one product or the other. And convenience comes at a cost. A bag of fast-setting concrete costs about a dollar more than regular concrete, though prices vary by store and location. So, if your project is small, the difference may not seem like much. But if the project’s big, you might be better served to use standard concrete. Imagine that you’re building a privacy fence that requires 60 bags of concrete mix, and the fast-setting option is $1 more. Going with standard concrete could save you $60! So, the decision is yours.

But remember: Whether you use fast-setting or standard concrete mix, stay safe — always wear protective glasses and rubber gloves.

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Photo Credit:  Stacy Ellen / Shutterstock.com