Every concrete contractor must have a complete set of tools to get the job done. Since concrete waits for no one, the right tools can make the difference between a successful pour and a potential disaster. Most of the essential tools are basic and do not require a significant investment. Owning these eliminates the cost of rental fees and the lost time picking up and returning the equipment. Some specialty equipment is more expensive and is worth the investment only if the tools are needed on a regular basis. Otherwise, it may be most cost-effective to rent specific items when they're needed.
Screeds are long, straight, stiff tubing or boards used to smooth and roughly level wet concrete shortly after it is poured. Screeds are available in different sizes and can even be project-specific, such as those used for building concrete bridges. For hand-screeding, the screed must be longer than the width of the concrete form so that it can ride along the top edges of the form as the concrete is flattened.
For many smaller jobs, such as sidewalks, garage and driveway slabs, and patios, a simple straight piece of dimension lumber, usually a 2 x 4, suffices as a screed. There are also commercial screeds available, which are often aluminum "boards" with a shape similar to a 2 x 4. They are sold in commonly used lengths, such as 6 ft., 8, ft, 10 ft, etc. Some commercial screeds come with leveling vials attached to them to make it easy to level slabs as the screeding is done.
Concrete work can be physically demanding and sometimes dangerous, and proper worksite safety practice requires the use of protective gear:
- Eye protection is essential for any worker handling concrete mixing and pouring. The Portland cement in concrete is highly caustic and can burn eyes.
- Hearing protection should always be worn when power saws, plate compactors, power mixers, or other power tools are operating.
- Breathing protection must be used during demolition or when pouring gravel or sand to prevent inhalation of cement lime and dust particles.
Rubber gloves are always needed when handling concrete. Concrete contains chemicals and admixtures that can irritate the skin. Cement in concrete draws moisture from the skin and can cause extensive damage over time. There are even cases of lifetime workers requiring amputation after many years of handling concrete with unprotected skin. According to OSHA, skin problems are a leading cause of lost work time for concrete workers.
Contractor-grade gloves for concrete work come in many types, with some offering maximum flexibility and others designed for maximum puncture resistance. Materials range from solid natural latex or synthetic latex (neoprene) to blends of rubberized cotton or nylon fabric. For work in cold weather, you can even purchase fleece-lined rubber gloves.
Rubber boots ensure you are prepared to step into concrete at any time. They allow you to work while standing in the concrete and at the same time protect you from skin irritation.
It is important for concrete workers to choose footwear that is not only waterproof and resistant to chemicals, but that is also comfortable to wear. Concrete workers often spend hours each day in their boots, so selection needs to be just as careful as with quality leather work boots. Pros suggest that rubber boots should have steel toes for safety and drawstring tops that seal the boot around your calves to prevent concrete from entering.
Wheelbarrows are needed to move small amounts of concrete or to carry tools around the site. They are also useful for taking concrete samples for slump tests or other assessment.
Wheelbarrows for concrete work should be heavy-duty tools with sturdy pneumatic tires that will hold up to the heavy loads and constant duty required on job sites. Trays made of steel or heavy poly are typical, with a capacity of 6 to 8 cubic feet.
A portable mixer allows you to mix small amounts of concrete at the job site. Mixers come in handy for pours that are too small to warrant an order of ready-mix, but larger than what you can conveniently mix in a wheelbarrow or mixing tub.
Portable mixers come in a range of sizes, from units that fit in the back of a pickup truck to those that can be towed to the job site. Both electric and gas-powered models are available.
Shovels are essential for moving small amounts of concrete around a pour to fill voids or depressions and to get to hard-to-reach areas. Shovels also are needed on-hand to remove excess concrete from overfilled forms. Most concrete contractors use square-ended shovels rather than rounded, garden-type versions.
A bucket or pail for water is handy for pours in very dry or humid conditions. A small amount of water added during the finishing process makes the concrete more manageable.
A laser level is now the standard (and preferred) tool for leveling forms and setting their elevation. They're also useful for establishing or checking the height of embedded pieces, such as bolts and other anchors. Laser levels send a beam of light to provide a straight level or plumb line. Unlike a traditional string line, the laser line never gets in the way, and it can remain true over a long distance.
Floating is an essential part of concrete work. It involves tooling the surface of the damp concrete with a variety of smooth metal or wooden surfaces with the aim of slightly raising liquid cement to the surface to create a smooth finish. Most metal floats are now made of magnesium.
A bull float is a large float used to smooth and level the surface of the concrete immediately after it is screeded. It typically includes a long pole for reaching across the form. Smaller floats are useful for filling small voids and smoothing areas close to the form edges.
Vapor barriers or retarders are used to stop moisture from evaporating from concrete surfaces, which weakens the concrete. Barriers also can be placed below the concrete before it is poured to prevent surface water from mixing with the concrete or to prevent dry base materials from pulling water out of the concrete.
Standard 6 mil plastic sheeting does not really work very well as a concrete vapor barrier. This thin plastic, more properly called a vapor retarder, does not stop moisture movement beneath slabs, though it works well enough when laid over concrete as it dries to help it cure. For a true vapor barrier beneath the concrete, a better material is sheet plastic that conforms to the requirements of ASTM E-1745, "Standard Specification for Water Vapor Retarders Used in Contact with Soil or Granular Fill under Concrete Slabs."
Groove Cutters and Edgers
Groove cutters, also called groovers, are used to create control joints on sidewalks, walkways, driveways, and residential slabs, where a concrete saw typically is not used. Many groovers have a horizontal plate with a vertical fin for cutting the groove. The plate often has rounded sides for shaping the edges of the groove.
A similar tool is an edger, which has one rounded edge that serves to mold a slightly rounded-over edge along the sides of a slab or sidewalk.
Curing Compound and Hand Sprayer
Curing compound is applied directly to a wet concrete surface to reduce cracks and help the concrete set at the desired rate. For residential and small commercial projects, the compound is typically sprayed onto the concrete with a hand sprayer.
A variety of power saws is common on a concrete job site.
- Concrete saws are used in demolition and removal of old concrete and sometimes are used to cut control joints the concrete is hardening. Essential when using a concrete saw is a good-quality diamond blade designed for cutting concrete.
- Standard portable woodworking saws, such as circular saws and miter saws, are needed to cut parts for wood forms.
- Reciprocating saws or chop saws with metal-cutting blades are used to cut rebar or other metal reinforcement materials.
A plate compactor is a large motorized tool that is used to compact granular surfaces, such as a gravel or sand sub-base, to create a dense, tightly packed surface for a concrete slab to rest on. They are most useful on uneven or unstable soils, where it is essential to achieve a stable base upon which to pour the concrete.
Vibrators are used to settle and compact concrete during pours or as concrete is being finished. The goal is to shake the wet concrete and eliminate air pockets so that the slab or foundation becomes more solid. There are four basic types of concrete vibrators:
- Internal (also called needle or poker): includes a vibrating probe that is immersed in the wet concrete
- Form: attaches to the outside of the concrete form to create vibrations that eliminate voids along the edges of the form
- Surface: attaches to a screed to vibrate the concrete surface during screeding
- Table: has a vibrating metal table for vibrating concrete inside a mold
Rain, snow, or drainage can lead to concrete forms full of water. Bailing out water by hand can use up precious time before a pour. A motorized water pump can get rid of the water much faster and with very little manpower.
Power Hammers and Drills
A great many jobs will require the use of contractor-grade power drills and rotary hammers. Both corded and battery-powered tools are now available. They are essential for many finishing tasks, such as mounting posts and railings to poured steps, or attaching sill plates and ledgers to foundations.
Contractors that offer specialty services or who accommodate very large jobs may need additional specialty tools, including:
- Polishers and grinders: Contractors who offer countertop fabrication or floor polishing will make use of a variety of walk-behind and hand-held tools for polishing and grinding concrete surfaces.
- Walk-behind trowels: While troweling by hand is still the norm, for very large surfaces, walk-behind trowels are becoming highly popular.
- Power screeds: Contractors who install pervious concrete (which allows water to seep through) now make use of motor-powered roller screeds that mechanically spread out and compress the concrete mixture to precise compaction.