4 x 12 Stair Stringer In Concrete
In the picture above the concrete was poured around the wood stair stringer. This can cause the wood to rot from moisture.
A good fix for this would be to cut the stringer and install a metal bracket underneath separating the wood from the concrete.
Here's an illustration of what the
4 x 12 stair stringer would have
looked like originally after it was built and actually sitting on top of the
concrete walkway. This would be better than having it sit below the concrete
walkway, but isn't the best way to build this type stairway.
I like to install a spacer under the stringers to provide some type of barrier or separation from moisture that can be absorbed through the concrete and into the wood, eventually causing it to rot or worse yet, attract termites.
Here's a side view illustration of what the stair stringer actually looks
like right now, after they removed the concrete walkway and re-poured it
around the existing stair stringer. In other words, the existing walkway
must've been damaged and needed to be replaced, yet wasn't poured exactly in
the same spot.
Another problem with a situation like this is that concrete and wood both tend to expand and contract and eventually there will be a gap between the concrete and wood, only adding insult to injury. These gaps will allow water to accumulate and form a pool around the bottom of the wood stair stringer.
This would be a bigger problem in areas where it rained often or where water was sprayed on a regular basis from sprinklers or cleaning the concrete walkway with a garden hose than it would in drier climates.