There are several things you must do to the concrete after it's in the footing and before it hardens. First, move your wheelbarrow or mixer as close to the footing as you can before mixing the concrete. Second, always pour a complete footing. If you need to mix another batch of concrete to finish filling a hole, do so before the first batch dries. Pouring fresh concrete over dry concrete creates a so-called cold joint in the hole where the new concrete won't adhere to the old. This situation will compromise the footing strength.
There are 6 steps to completing this project:
Guide concrete into the footing hole with a shovel. This type of power mixer allows you to mix at the footing and pour directly from the mixer into the hole. You also can pour from a wheelbarrow, but it's better to use a round-nosed shovel and scoop the concrete from the wheelbarrow. Some concrete may slope outside the form, but don't scrape it and put it into the footing—dirt weakens the mix.
Plunge a length of scrap wood into the concrete when the footing is almost full. Work it up and down to eliminate air pockets. On footings deeper than 2 feet, do this when the footing is half full and again when completely full. Remove excess concrete with a length of 2x4 and level the top of the footing after overfilling the form slightly. Push the 2x4 back and forth in a sawing motion as you pull it across the tube form.
Either reset the layout lines or use a story pole to mark the centre of the footings. Insert the hooked end of a J-bolt into the wet concrete at the centre of the footing. (The J-bolt can be off just a little — you'll position the post base precisely because it's adjustable.) Leave 1 inch of the threads showing above the surface concrete. Square the J-bolt to the footing. Add concrete and smooth. Let the concrete cure for 48 hours. In hot weather, mist the concrete occasionally so it doesn't cure too quickly, which may make it brittle. If it is hot, cover the footings with clear plastic sheeting after misting.
Set an adjustable post base over the threads of the J-bolt and tighten each nut so the base can still be adjusted.
Line up the post bases parallel to the house by setting a straight 2x4 or other long straightedge across the footings and against the flanges of the post bases. Measure from the house to the edge of the 2x4 and adjust the post bases until they are equal distance from the rear wall. Mark each base position on its footing with a pencil. These marks will help you gauge anchor position adjustments as well as provide a reference point if a post base is knocked out of alignment. Then line up the post bases on the sides of the site, restringing the layout lines if necessary to keep the bases in the same plane.
Measure the diagonals after aligning all the post anchors. Make adjustments as necessary until the measurements are equal. (You may have to readjust the other post bases, too.) This makes the post positions square to each other and to the house. Tighten each nut with a socket wrench to secure the post bases. The anchor should not move, and do not over tighten the nut.
