I devised a way to build landings that is very safe yet much easier to do than digging holes for sonotubes and dragging down buckets of concrete by hand. I use four post spikes per landing - one in each corner.
While any brand of post spike will likely work I discovered a type of post spike (sometimes called a ground spike) where the top swivels. This swiveling capability makes the whole approach work fabulously as it makes up for the inaccuracy of the installation process. Driving the post spikes in to the right location to match the dimensions of the landing is an inexact science at best. Sometimes the spike will just not drive down in the location you need it to because there is a buried stone in the way. At other times it will twist as you drive it in to the ground. All these ills are mitigated by the swiveling action of the post spike. In most cases the direction of the post can be turned and twisted to match up with the superstructure of the landing.
My Process goes something like this:
Step 1: Build the super structure for the landing. Most of my landings were 3x3 feet, 4x4-feet or 6x6-feet square so I would begin by building the superstructure of the landing but NOT install the floor (top) of the landing.
Step 2: Use the landing supper structure to determine where the post spikes need to be placed. I plumb bob is really handy for determining the location.
Step 3: Drive the post spikes in place. I would install one then temporarily install on post and recheck my placement for the next post spike and then drive it home. I would continue this process untill all four post spikes are in place.
Step 4: Install the posts. Starting with the uphill posts, measure, cut and install the posts into their respective post spike. A level comes in real handy during this process to level the posts as well determine the level of the landing so that you can determine the length of each post. When this step is complete, all the posts are cut to size, installed in the post spikes and the landing is lying around the posts.
Step 5: Install the landing. Using a level attach the landing to the top of the posts.
NOTE: Sometimes I just installed the posts in the spike and to the landing and then cut them off afterwards with a Saws-all
Step 6: Secure the posts to the post spikes. This generally requires a wrench and a few nails.
Step 7: Install the flooring on the landing.
Step 8: Get two beers, sit on the landing, and enjoy your handiwork with your helper - yes you will need a second pair of hands to build the landing!
NOTE: The posts usually are secured on the inside of the landing, however, in the landing above they were installed on the outside of the landing superstructure. This is because I removed a previously built landing and reused it. In reusing the landing it was easier to install the posts on the outside.
Reconstructing the Stairs to the Lake: Part 1
Reconstructing the Stairs to the Lake: Part 2
39 Steps... Heck no we have 104!