Grading and concrete forms details, If you are planning to pour a large area, you will find it easier to do if you block it off in smaller squares that you can fill one at a time. Some week-end masons have found that a 5-foot square of 4-inch concrete is just about par for a Saturday afternoon for a man working alone. With help, of course, the area can be increased, but you will still find it convenient to put it down chunk by chunk.
Best way to block off the area is to set either permanent or temporary header hoards in place. For permanent headers, use redwood, cedar, or some other rot-resistant wood ; for temporary forms, any straight-grained wood will do. Use 2x4's for straight lines, double 1x4's or tripled 1/2x4's for curves. Green wood or wet wood will bend more easily than dry.
Coat temporary forms with crankcase draining, or whitewash so they can be removed without sticking to the concrete. If you are going to remove the forms, pour sections alternately. After these have hardened, enough to hold their shape, remove the form cross strips and pour the intervening slabs.
The permanent headers may be locked into the concrete by driving spikes part way into them so they will protrude into the concrete. However, it may be necessary someday to remove the headers —they do wear down, splinter, and discolor—so you may prefer to leave them loose. Concrete will shrink away from them when it sets. Brace all forms and headers firmly with stakes driven deep into the ground. Plastic concrete has a may of bursting its way out of fragile forms.
Set headers so their top surface is flush with the grade you plan for the concrete. Check levelness with a spirit level set on top of a long straight board rested on opposite headers. Adjust height of headers to permit slope away from the house. Plan for a drop of 3-inch per foot.
Level the soil with your shovel and remove weeds, sod, trash. If you have to dig out the soil, overfill the cavities with dirt and tamp solidly in place. To settle the soil, wet it two or three times ahead of pouring day. Night before, wet area thoroughly so the soil will be damp when you pour onto it. Dry soil will suck moisture out of the concrete and weaken it. Thanks for reading this page on Grading and concrete forms. For more basic carpentry tips continue to visit this website