Every good deck starts with a firm foundation. When building your deck, you’ll need several bags of concrete to create the footings, walls, and piers to support your deck. This concrete calculator gives you the built-in formulas you’ll need to help you calculate how many bags of concrete you will need for deck footings, supports, walls, pads and/or patios. From there, you’ll be able to plug in your specific project measurements to find out just how much concrete you’ll need to get the job done.
In addition to calculating how much concrete you’ll need, you can also use this page to learn more about the basics of working with concrete, cost, and some simple calculations. Ready? Let’s get started!
The words “concrete” and “cement” are often used interchangeably, however, they are two very different things. Concrete is a mixture of cement and other items, such as sand or gravel. Cement is an ingredient in concrete and is the “glue” that helps hold the mixture together. Once concrete hardens, it can be used to create stairs, sidewalks, landing pads, or other solid surfaces, as well as footers for decks.
Typically, concrete is sold in pre-mixed 60-lb. and 80-lb. bags. Most 60-lb. bags of concrete have a retail value of between $3.10 and $3.50, although you may be able to buy it cheaper in-bulk. An 80-lb. bag of concrete can cost between $3.50 and $4.00 per bag. However, you may be able to find it on sale for $3.00 or under, or get a discount if you purchase it in-bulk.
When trying to calculate how much concrete you’ll need, think of your project in terms of cubic feet and cubic yards:
With this formula in mind, you’ll be able to calculate just how much concrete or cement you’ll need for your project:
Still planning your deck? Check out our deck planning resources to make sure you have everything you need.