Tips on Pouring Large Concrete Slabs
- Start with a firm foundation and plan your transporation and screeding carefully.Jupiterimages/Photos.com/Getty Images
If you are planning a small concrete project, you can probably buy and mix the concrete yourself in a wheelbarrow. For large projects, however, you will need to bring in a cement truck and make more elaborate plans. Always prepare by having the foundation firmly set and measured precisely, with all the necessary supports, so that it can withstand the weight of the concrete. When ready to lay the slab itself, remember to arrange for proper on-site transportation and leveling of the concrete. - Entry routes become complex when a cement truck is involved. For laying a slab in your driveway, you may be able to pour directly from the truck. However, for a patio or garage, you will need to move the concrete from the truck to the site. The most effective method is a cement pump, but these are expensive to rent. A cheaper option is using wheelbarrows.
- For large slabs, steel reinforcements are a good idea. Steel mesh will keep the concrete from cracking as easily, but you will need help to pull the mesh up through the concrete to the center of the slab for maximum stability. If you use steel rods, position them so that the concrete can flow easily underneath and fill in all empty spaces.
- If using a wheelbarrow, try to dump the loads of concrete evenly. Have someone work with a shovel or rake to draw out the concrete as much as possible, so you can fill in the center of the slab as well. You can't do this by yourself, so find friends who have experience laying concrete.
- Screeding is leveling off the concrete slab with a straight edge. Draw the straight edge along the concrete slab so that it rests at the edges and pulls a perfectly level surface as you move forward. Screed more than once: the first time is likely to reveal depressions that need additional concrete.
- Weather is always an important consideration. Hot weather will cause the concrete to dry very fast, so if you are expecting hot conditions add a concrete thinner into the mixture (do not just add more water). If it looks like it rain, arrange for an outdoor slab to be protected from the elements with a tarp.
Plan an Entry Route
Use Reinforcements
Evenly Distribute the Concrete
Screed
Prepare for Weather
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