How Much Concrete Do I Need?

You’ve drawn your concrete design to scale, you’ve mapped out its location, and you’ve gathered your DIY concrete and masonry tools. You’re ready to get to work. But how much concrete will you actually need? No one wants to have way too much excess; and no one—no one—wants to be partway through a poured concrete project and realize they’ve run out of concrete.

Luckily, BLACK+DECKER™ Complete Guide to Concrete & Masonry 4th Edition has a tried-and-true formula for estimating how much concrete you’ll need for any project.

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BLACK+DECKER The Complete Guide to Concrete & Masonry, 4th Edition

How to Estimate Concrete

Plan drawings are especially valuable when the time comes to estimate materials. With your drawing in hand, calculate the width and length of the project in feet, and then multiply the dimensions to get the square footage. Measure the thickness in feet (four inches thick equals one-third of a foot), and then multiply the square footage times the thickness to the get the cubic footage. For example, 1 foot × 3 feet × 1⁄3 foot = 1 cubic foot. Twenty-seven cubic feet equals one cubic yard.

Coverage rates for poured concrete are determined by the thickness of the slab. The same volume of concrete will yield less surface area if the thickness of the slab is increased.

Unless you need to improve the drainage or the soil stability of your building site, the only other raw material you’ll need for most pours is sub-base material, such as compactable gravel. Gravel is normally sold by the cubic yard. For a slab with a four- to six-inch–thick sub-base, one cubic yard of gravel will cover 60 to 70 square feet of surface.

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Estimate the materials required based on the dimensions of your project. BLACK+DECKER The Complete Guide to Concrete & Masonry, 4th Edition

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This chart shows the relationship between slab thickness, surface area, and volume. BLACK+DECKER The Complete Guide to Concrete & Masonry, 4th Edition

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This chart shows the number of bags of concrete mix a footing requires. BLACK+DECKER The Complete Guide to Concrete & Masonry, 4th Edition


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book2Love all of your masonry and concrete projects–knowing that you did them yourself!–with help from our experts.

No projects offer more aesthetic or financial satisfaction than DIY concrete and masonry projects. Homeowners can routinely save thousands of dollars in labor costs by buying and installing materials that are readily available. This updated 4th edition of  BLACK+DECKER The Complete Guide to Concrete & Masonry includes traditional techniques for laying concrete, adapted to make them easy for ordinary homeowners, and also features completely modern materials and techniques, such as tumbled concrete pavers, acid-etching for colored concrete slabs, and important green paving options, such as rain-garden arroyos and permeable pavers.

Several cutting-edge projects, like polished concrete countertops and stamped concrete walkways, are included in this book. An exposed aggregate patio, a reinforced concrete block wall, and the latest tools and materials for handling new products are featured. A completely new section on foundation walls shows you all the options, including the latest structural insulated panels, that are now more DIY friendly than ever.

No homeowner or do-it-yourselfer will want to miss this chance to master the best methods to create lasting beauty around the house.