When installing a new decorative concrete driveway, patio, sidewalk, or floor slab, what you use for reinforcement is as important as the concrete placement itself. There are a number of reinforcing materials available for your project, listed here is an overview of your options along with tips on how to choose the best type of reinforcement for your specific concrete project.

Concrete slabs and walkways are high in compressive strength, which makes them great at resisting compression forces and impact. But when it comes to tensile strength, or the capacity to resist earth movement from moisture or natural forces, concrete will crack. Tensile strength of concrete is only about 15% of its compressive strength.

This is why concrete slabs require some type of reinforcement. It provides the tensile strength that concrete lacks to help it withstand tension forces caused by subgrade settlement, heavy loads, drying shrinkage, and thermal expansion and contraction. Reinforcement doesn’t actually prevent cracks from forming in concrete, but it does help limit the width of movement and severity of any cracking when it does occur, potentially saving you from costly repair work or replacement.

What Are Some Concrete Reinforcement Options?

Reinforcing Bars

Fiberglass rebar rods from 3/8″ to 1″ in diameter are embedded in the center of a slab exactly like steel rebar to create a grid that extends lengthwise and crosswise to help the concrete better resist pulling and bending forces. Ridges or irregular patterns in the surface of the rebar allow the concrete to adhere to it and create one solid structure. Fiberglass is a new great product that will not rust or corrode and has a bit more flexural strengh than steel rebar. As per most manufacturers specifications.

Rebar steel rods from 3/8″ to 1″ in diameter are embedded in the center of the slab or wall to create a grid that extends lengthwise and crosswise to help the concrete better resist pulling and bending forces. Ridges or irregular patterns in the surface of the rebar allow the concrete to adhere to it and create one solid structure. Stainless steel rebar is also available, but is higher in cost and generally reserved for projects where corrosion is a major concern.

Epoxy-Coated Rebar

These are steel rebar completely covered in a coating of epoxy to minimize the chances of corrosion. Higher in cost than simple steel bars are typically used for slabs in marine environments or that are regularly exposed to elements.

Welded Wire Fabric

Also called wire mesh is often used as an alternative to steel rebar in residential and commercial concrete slabs because the wire fabric can be placed more quickly than individual bars, which reduces the overall cost.

Synthetic Fibers

Is a type of secondary reinforcement consisting of small fibers that are mixed right into the concrete as a way to reduce plastic shrinkage but is only an additive rather than an alternative to reinforcement bar. These synthetic fibers will not provide structural reinforcement, like reinforcing steel, they will only improve concrete’s flexural strength and resistance to abrasion and impact.

Synthetic fibers do not rust or corrode, but they are no substitute for steel reinforcement in concrete slabs that will be supporting heavy loads. There’s also the chance that the fibers will be visible on the concrete surface, like fine hairs or fuzz, although proper finishing will usually prevent that

Which reinforcement material is best for our concrete project?

This generally depends on the purpose of the concrete slab, is it vehicular traffic loading or residential foot traffic only. Using steel reinforcement will give your concrete slab additional structural capacity and is especially important for a driveway that will be expected to support large trucks or heavy traffic. But for the typical residential concrete driveway, patio or sidewalk, wire mesh is a great (and less expensive) alternative.

Fiberglass rebar is now readily available nationwide and is lightweight, easily cut to size and placed and will not corrode or rust, is more resilient to tensile stresses caused by settlement, heavy loads, and thermal expansion and contraction making it a great option for many reasons.

Before having any type of decorative concrete slab installed, be sure to discuss reinforcement options with your local licensed concrete contractor.