Unless your patio is going to be the size of your driveway, you can pour concrete you mix yourself. Buy your favorite brand and follow the instructions on how to mix. Once you have your concrete mixed, start pouring in the frame over the leveled and flattened ground.
It's not too difficult to DIY a concrete slab. And, if you mix it yourself, it's the cheapest way to make your slab. For most do-it-yourselfers, the best material for building a concrete slab is a ready-mix, crack-resistant concrete product. The wet mix is poured into a prepared wood form, then left to cure.
Is it cheaper to pour concrete yourself? Yes. In general, you can save up to 40% or more if you pour a concrete slab yourself. If you decide to mix your own concrete, you can save even more.
It's easy to pour and build a backyard patio made of concrete in this How To article. On a small scale, concrete is fairly easy to work with, but installing an entire patio can be a challenge. It is possible to build an attractive concrete patio yourself, but careful planning and preparation is necessary.
Doing the Work Alone. Trying to pour and finish a concrete slab by yourself is the surest way to fail. Since you really don't want to do it over, find as many friends and family members as possible to help you do the job. Do not start the job until you know for sure you've got people present to help.
If the weight of the concrete deforms the dirt base in any way, the entire concrete structure will be flawed. All of that is not to say that it is impossible to pour concrete over dirt. You can absolutely do it successfully, but you need to follow a specific process.
Standard concrete floor slab thickness in residential construction is 4 inches. Five to six inches is recommended if the concrete will receive occasional heavy loads, such as motor homes or garbage trucks. To prepare the base, cut the ground level to the proper depth to allow for the slab thickness.
Most driveways require at least 6 inches of stone crushed or gravel. Medium gravel, which is 1.8 cm (3/4 inch) in diameter, is the best material for a concrete base. To cover a 4 inch thick concrete slab, you'll need 3 inches of gravel.
It is cheaper to mix concrete by hand, but it will become less cost-effective as your project size increases.
The general rule of thumb is that concrete takes about 28 days to dry for every inch of slab thickness. Within 24 to 48 hours, the concrete will be ready for foot traffic.
Although dry pouring of concrete might be fine for filling fence-post holes, it should be avoided as a placement method for concrete slabs if you want the concrete to look good and last for the long term.
Most concrete contractors want a mix of coarse and fine aggregate to create a compactable base that is going to be safe for settlement and drainage. Crusher run (a mix of crushed stone and stone dust) and #57 coarse aggregate are two of the best base materials for concrete slabs.
one 20kg bag will cover an area of 1.1m2 to a depth of approximately 10mm. or 108 x 20kg bags equates to one cubic metre of mixed concrete.
In general, however, you can expect that concrete needs to be at least four inches thick in order to avoid cracking. Of course, the best way to ensure that your concrete doesn't crack is to hire a professional contractor who has experience working with concrete in your area.
No, you do not need rebar for a 4-inch slab of concrete on grade. A 4-inch-thick slab cast on the ground and in permanent contact with it will float and rebar is not required. Rebar is recommended on concrete measuring 5 – 6 inches thick.
As a general rule, stay away from using sand as a subbase. You're better off using gravel; your concrete will last longer and have less of a chance of cracking over time.
Rebar is not necessary for every concrete project. The general rule of thumb is that if you are pouring concrete that is more than 5 inches in depth, you are probably going to want to add in some rebar to help reinforce the entire structure.
Technically you can, but you really shouldn't pour concrete over grass. To maintain its tensile strength, concrete needs to be laid on a firm, even, and dry foundation. Grass and soil will naturally channel moisture into the concrete from below, which will likely result in it cracking over time.
Concrete that is not moist-cured at all dries too rapidly, and reaches less than half its potential design strength. It will also have a greater number of shrinkage cracks.
Many construction specialists recommend watering it down five to ten times per day, for the first week, starting 2-4 hours after it has been poured. The first two to four hours lets the concrete “finish”, which refers to the setting process.
Plan to pour concrete before 10 a.m. or after 8 p.m. in order to avoid the hottest part of the day. If you are concerned about the temperature while working on a summer project, consider pouring concrete at night to give the mixture the best chance to harden and cure before the sun comes up.