Thinking of doing a sidewalk or patio project yourself? It can be rewarding and doing it yourself can save you some money. But be prepared—pouring concrete is hard work and you'll need forms, the rights tools and plenty of help.
As you start planning for your project, take into consideration what you will need...
You may have decided by now to hire a concrete contractor to do the job for you. You can contact one of our plants where our dispatcher can recommend qualified, skilled contractors for you to choose from. If you're still interested in doing it yourself, continue reading for some tips and general information about pouring concrete on small jobs.
Dig out the area where the concrete will be poured. Remove tree roots, stones and heavy clay.
Use sturdy 2-by lumber for the straight areas. Use 6 inch strips of hardboard siding for the curved edges. Hammer in stakes and attach lumber to them. Place stakes at frequent intervals to prevent blowouts (every 3 feet). To prevent water from collecting on the pad, slope it by dropping one side of the form _ inch for each foot of concrete.
Apply sub-base materials if needed. Some conditions warrant the use of steel fiber or steel mesh. Put in expansion joint (every 30 feet and where you abut to other masonry surfaces) to prevent heaving, cracking or buckling.
Have on hand the following tools to place and finish the concrete. These can be purchased or rented from your local hardware store or rental company.
Schedule the delivery on a day when rain is not expected. A rainstorm in the middle of an outdoor project could be a disaster. (See our Quality Control section for tips on hot and cold weather pours). For a five-yard pour, you will need between three to six hours to complete the job.
Locate the nearest High Grade plant and call the dispatcher to place your order. To secure a time slot, place the order two to three days ahead of time if possible. We can deliver as quickly as within _ hour notice if our schedule allows. We will need the following information:
Before the truck arrives you should:
As the concrete is unloaded, start with the concrete that was placed first and finish with the concrete that was placed last. (When working on a slope, work upwards on the slope.) Spread the concrete with a square ended shovel, a concrete rake or a come-along. Avoid using a garden rake or other tools that will segregate the concrete. Lightly tap the edges of the forms with a shovel or 2x4 to release air bubbles and consolidate the concrete.
Use the screed (ex: a straight 2x4) to level the concrete by resting it on the top edge of the forms, tilting it forward and drawing it across the concrete with a sawing motion—always keeping a little concrete in front to fill in low spots. Screed (or strike off) the concrete twice - while leveling and grading it also consolidates the fresh concrete.
Begin using the bull float as an area is screeded. Do this before the bleed water comes to the surface in order to ensure the durability of the slab. Draw the bull float over the concrete in the opposite direction of the screeding if possible. Push first then pull back to level the surface. One or two passes with the bull float will smooth the concrete without sealing the surface. [Warning: Over use of the bull float will seal the surface preventing the bleed water from migrating to the surface. It may form blisters underneath the surface which will delaminate and scale as the concrete ages.]
Bleed water will migrate to the surface from the fresh concrete in small pools. It will be reabsorbed or will evaporate. You must wait until the bleed water disappears and the surface becomes dull to begin the finishing process. Finishing while bleed water is present can cause blisters, crazing, dusting and scaling later on.
Use the edger and groover for the first pass when the concrete begins to firm up to form the rough shape. Round out the outside edges with the edger. Cut in joints with the groover (if you haven't put in control joints) Guide the groover with a board on the first pass to achieve a straight line. (See Construct Joints in Concrete Slabs). Use the tools to push the gravel in the concrete mix away from the rounded edges. Repeat this process as the concrete hardens. The last pass polishes the final shape and smooths out inconsistencies. Avoid overworking the concrete—doing so will weaken the concrete.
If texture and a non slip surface is desired, use a concrete broom. Broom the surface by placing a dampened broom on the other side and gently and slowly pulling it toward you. Overlap strokes by six inches. If the texture is too rough or if clumps of concrete start gathering, the concrete is not ready. Smooth with a mag float and try it again in 15 minutes.
Curing should begin when it is possible to walk on it without marring it and consists of keeping the concrete moist by sprinkling or misting with water and covering with burlap or plastic. The concrete must be kept consistently wet. This should be done for 5—7 days depending on the temperature. This allows the concrete to gain strength by a chemical reaction called hydration. Or liquid curing compounds can be applied to seal in the moisture but are not recommended for concrete poured late in the fall.
Sealing compounds can be applied to provide protection from salts and water penetrating the concrete surface. It is recommended to seal exterior concrete such as sidewalks, patios and driveways. Again they are not recommended for concrete poured late in the fall.
The above instructions are only basic instructions for what can be a difficult job. Many variables can impact the success of your job. We strongly recommend that you read our Quality Control Section and visit the website rmca.org/aboutconcrete/cips/CIP14p.pdf for further information and guidance in placing and finishing concrete.