According to Decksgo,
"It certainly is possible to use screw piles or helical piers as they are also called, to support the various stair stringers. Helical piers usually have the U shaped post bracket somewhat elevated above grade and if you adapted the bracket to accept a 2x stringer then the stringer would be forever above grade and should also stay dry for its lifetime.
Keep in mind helical piers are quite expensive and are generally an engineered solution which means a contractor must install them using special hydraulic equipment and they can sign off on its performance level based on torque ratings achieved. They can also drive the piers well below frost levels and so the piers will never move relative to the stringers."
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What is a helipier?
Used here in building cliff hanger homes with caissons.
Wealthy people that want their hillside or beach front homes at any price . . .
Bob, I couldn't find any info for using piers on stairs, but here are some videos that might help you construct a staircase.
What does your local Building code say? That's where you should start. Typically used for deep foundation issues to secure to foundation. It will help, could you provide more info on your project? Is this a remodel or repair? Soil conditions?
I have a steep incline to get from our dock to the cottage. I’m not certain what the soil conditions are yet, but in the event heli piers would be suitable, I was curious about their load-bearing capabilities. Thanks for getting back to me.
Great! Now I know what you are doing! First thing I would do is get a soil compaction survey. Hire a soils enginner for an analysis. If you do it right the first time, it will last generations. If this is an area that receives a lot of rain or snow, I would not skip this step.
Another option would be to terrace the area and do it in a switchback pattern to get from point A to point B. Could be wider in spots to have a bench for viewing or resting.
Some valuable suggestions. Thanks a ton