How long can thin pressure treated wood last in soil? (Lowes, building)

[rhbj03]

I am building a trail on a hill. There will be sections of stairs. My neighbor has built stairs out of wood; if this is viable I can do the same, but I want to understand how long this design might last.

Neighbor's stairs look like is made of solid wood and plywood, and held in place by wooden stakes driven into soil. I can use all pressure treated douglas fir 2x6 boards, I think that's more durable than any plywood. But for the wood stakes, if I cut PT boards into 1/2" thick strips to be used as stakes, just like in the picture, how long do you think these stakes can last in soil before they rot away?

[wit-nit]

Hard to say without knowing soil conditions. But if it's consistently wet then 1-2 years probably.

[rhbj03]

Originally Posted by wit-nit

Hard to say without knowing soil conditions. But if it's consistently wet then 1-2 years probably.

Yes it is consistently wet; the area gets about 40" of rain a year.

1-2 years, even 4-5 years, seems too short-lasting for me to spend the effort.... What might be a longer-lasting option, besides going to concrete?

[K'ledgeBldr]

6X6 PT (rated for ground contact)- it will last your lifetime


https://m.youtube.com/watch?v=CLIXGZI49zc

[LIcenter]

As K'ledgeBldr says above. Just make sure it is CCA treated, and not ACA. You will need to go to a good lumber supply to find it. Stay away from the big box stores, unless you want to re-do it in the not too distant future.

[cdelena]

It does depend upon the weather but I have found water is usually good as it displaces the air so deterioration is reduced. My stairs are framed with 4x8 PT lumber and filled with gravel for the steps themselves. I have seen no deterioration in ten years and expect they will last much longer than I will.

[ChessieMom]

Originally Posted by rhbj03

Yes it is consistently wet; the area gets about 40" of rain a year.

1-2 years, even 4-5 years, seems too short-lasting for me to spend the effort.... What might be a longer-lasting option, besides going to concrete?

Use rebar instead of wood stakes.

[rhbj03]

Originally Posted by ChessieMom

Use rebar instead of wood stakes.

if using rebar, does it have to be any special type with special protective coating?

Also, how do i secure the wood boards to the rebar?

[thecoalman]

The rebar would last a very long time, certainly more than the wood.

If you are using 4*4's or 4*6's you drill holes through the center, preferably a half inch drill with auger bit that is sized for the rebar. Careful it will bite you. Lowes has fairly cheap hammer drill I purchased a while ago, it does the job for the homeowner and if you ever need to drill through masonry you now have the tool for the job.

https://www.lowes.com/pd/Skil-7-Amp-...vs0BoCwtrw_wcB

[Ghengis]

I used 1" green treated boards cut into stakes to secure 8", green-treated boards as edging, that are going on 20 years in a fairly wet area of the yard.