"Jim" wrote in message
om...
We had a PT deck, with steps leading from the lower level
(basement/ground) to the upper deck (1st floor). The steps were 3'
wide, and we had a series of 2, 2x6 on each riser, for a total of 11
risers. We had two stringers for the steps.

We had the PT flooring on our deck replaced with TimberTech. On our
steps, we used 5/4" planks. The 5/4" planks have a 16" spam
requirement, which means we now need to add a 3rd stringer in the
center of our steps. Unfrotunately, the steps were put up before we
realized the spam requirement.

Is it possible to add a 3rd stringer (down the middle) of 2x12 without
taking off the steps?

Yes. If there is room to get in there. You need to consider how you support
it at the bottom and how it attaches at the top. If you can figure that out
then it should be no problem to fit a new one. If you "had it replaced" then
it seems that the problem lies with the person who did the replacement. They
should have noticed this at the time. Depending on the deal you had with
them, I'd consider having them come out and pull the planks off and then add
the stringer. They would have to be pretty clueless to put that stuff down
with a 3 foot span. You would notice a problem after you installed the first
board.

If yes (or even if no), what is the easiest way to make another
stringer to match the current two?

Get some cardboard. Fit a square into each angle formed by each step.
Tack them on to the existing stringer.
Tape them together.
Cut along the bottom of the stringer.
Untack.
Place on new 2x12.
Mark
Cut.

THANKS in Advance...

-- Jim