Upper Rounded Stair Tread
We attached the same piece we cut for the bottom from 1-1/8 inch
plywood to the top of the upper rounded stair tread. You make one
pattern for the bottom and use that to trace the top piece of rounded
After we have cut the two rounded upper and lower pieces. You will glue the two pieces upper and lower one to the concrete and one to the underneath of the upper tread. You will have to nail or screw the upper pieces of plywood together.
Rounded Stair Riser Base
Round Stair Tread and Riser
The picture you are looking at right now is the start of nailing the plywood riser strips on to the rounded stair tread. Cut some plywood strips 1 1/4 inches wide by the riser measurement height and then you can nail on or screw on the plywood riser strips to the rounded base pieces.
The number of plywood riser strips will depend on how long your round base will be. So cut as many as necessary. You can also space the strips out between a quarter inch and 3/8 of an inch in between each strip.