Get Help With Pouring Concrete
Photo of pouring concrete by Gregs Landscaping/Flickr.
For those who plan to do it themselves, getting help with pouring concrete is recommended, because the process involves a lot of physical labor and it can be complex. A second pair of hands (or more) will help it go much faster, and ensure that it’s done properly, preventing the need for costly fixes to address problems like an uneven pour or cracking caused by poorly-cured concrete. Numerous detailed guides are available help people prepare for concrete projects, and it is advisable to consult these as well as the local building code to plan the details before initiating a concrete project.
Before any concrete can be poured, it’s necessary to prepare a substrate. Concrete needs to be poured on a properly prepared surface so it will last without cracking, subsiding, or developing other problems. Typically, this starts with digging out the area of the pour and compacting the soil to even it out. Next, a layer of gravel or a similar material will need to be added and compacted to create drainage and a level surface for the pour. It’s especially important to add a gravel substrate in regions where it freezes in the winter and concrete pads can be prone to ice damage.
Once the substrate is complete, it’s necessary to set up for the pour. At a minimum, this requires forms, made from wood, plastic, or composite material, which contain the concrete while it’s wet. Premade forms are available at some hardware and home supply stores, and it’s also possible to build them from scratch; this is another area where help with pouring concrete can be useful, because building and setting up forms can be time consuming.
It is advisable to use levels and string to make sure the forms are set up and marked off evenly. For large projects or when the building code requires it, the concrete will need to be reinforced with rebar or a similar material, which must be set up before the pour. Cross-pieces as well as perpendicular bars add strength to the concrete and reduce the risk of buckling, cracking, or subsiding. Typically the building code provides precise specifications for the amount of reinforcement needed.
Once everything is in place, it’s time to pour the concrete; and incidentally, cool, humid days are good ones for concrete pouring, as high heat or extreme cold can interfere with the process. It’s possible to order it pre-mixed, in which case it will be delivered in a concrete truck, or it can be mixed on-site with water and the desired aggregate material. The best options for mixing materials depend on how the finished concrete will be used; an ornamental retaining wall for a flower bed, for example, doesn’t need to be as strong as a foundation pad. Help with pouring concrete is critical during this stage, as it needs to be handled and spread quickly.
For large projects, it may be necessary to use a tool called a concrete vibrator to shake the concrete, eliminating air bubbles and pockets that could weaken it. On smaller projects, the concrete needs to be pushed with shovels or other tools into every corner to make sure it’s thoroughly distributed. As the water starts to wick away from the surface, it can be screeded, a technique involving the use of a flat trowel, board, or similar tool to smooth the surface. If a textured finish is desired, a broom can be run across the surface to make it rough; this can be useful on walkways and driveways to make them less slippery in the winter. Expansion joints can also be added to allow the concrete to expand and contract with the weather, preventing cracking.
After concrete is poured and smoothed, the work isn’t done. It still needs to cure, a process which takes around a month; and technically, concrete keeps curing even after this point. This is a critical phase in the project, as poor curing can weaken concrete and cause problems in the future. If the weather is going to be extremely cold or hot, the concrete should be covered to keep it at a more regulated temperature, and it may need to be sprinkled with water in dry weather so it doesn’t dry out too quickly.
For two to three days after pouring, the concrete will not be able to wear weight. Once it’s firmed up, it can technically be walked or driven on, but it’s a good idea to let it cure in the open for as long as possible, especially with projects where the concrete is just the beginning, like a house or extension.
As concrete cures, it’s also a good idea to think about sealing. While concrete is an extremely durable building material (remains of Roman buildings over 2,000 years old can testify to that), sealing helps it last longer and stay in good shape. Concrete sealants can limit seepage and stains to keep a surface clean and in good condition, and an assistant can help apply a sealant quickly and efficiently.
s.e. smith writes for Networx.com.