Not clear on what you are asking. If you have an existing open back stair and are interested in putting concrete or plaster treads on, you should think twice. the unsupported span between the two sides (stringers) will allow the tread to deflect and cause concrete and plaster to crack and maybe even snap in two. TO do this well, it will require a well reinforced base to then put a veneer on.Good luck!

Thank you for responding - I have attached a picture of the existing staircase. I want to remove carpet - underneath there are two wood beams that make up one riser/tread. Also, want to remove the banister and replace with cable. Do you have any suggestions? Going for a modern look.

Picture=1,000words.. Find a pre finished laminate or even a cork and glue right on to the treads. Make sure you do all sides. Take all the pickets out and leave the rail and newel post. Cover the newel with 1 x or even purchase a pre made newel (will require removing rail. then put your cable in and there you have it.

The prefinished laminate will work on the front and underneath the riser with the glue? So, no on cement?

Cement? do you mean concrete? or do you mean a cement to bind?

Originally I was asking if you could do a decorative sleek cement/concrete over the wood risers, but it sounds like that will no work. Correct? For the laminate, will the glue be sturdy enough to hold on the underside of the riser? Are you suggesting regular laminate, or do they make laminate for risers?

One of my friends used rebar for the spindles and it looks very industrial cool. Definitely made the place edgier and no one misses the old oak spindles. :) Good luck.

Sounds cool - What about the risers? See previous post. Thanks again.

The Concrete needs a thickness just to old itself together. Causes a problem when you build up stair treads because it makes the first stem really high and the last step (going up) really short. Better to stick with lam. Also like the rebar idea. Remember to keep with in code. Space between cable or rebar needs to be less than 4".

Risers are the vertical pieces that run up the back of the stair. Yours are riser-less... Here's a trick for the glue on the underside. Use PL (Panel Adhesive). pre cut the wood and make sure it fits. Apply the glue and stick the piece in place and then immediately pull it off and let it sit for five minutes. Then the glue will act like contact cement and once applied will stick great. Good Luck