How do you transition from stair tread to landing? The stairs have two landings halfway up the stairs. The all-in-one stair tread is about 12+ inches deep so they cover an entire step. What do you do when you come to a landing or the very top step? (Top step will transition into a wood floor.) Do you cut the tread short and put planks behind it? Do you leave it at 12+ inches and then put planks behind it? I assume you should router a groove on the plank side regardless if you cut it short?
Related article: Installation Tips for Stair Treads
(Cabinet and Millwork Installation Forum)
From contributor B:
All you have to do is use a piece of landing tread. If the area is going to be floored with hardwood, then you put the tread down and the hardwood guys, usually the stair guys, run the hardwood up and butt to the tread, same with carpet.
I liked to keep the top tread the same width if possible, even though the top newel generally interrupted. But I would narrow it if it would project beyond the adjacent wall on the other side of the stairs (presuming there was one). And, yes, I do dado both the balcony bullnose and the landing bullnose. I would also rip splines and tape them to something close by so the laborers wouldn't shitcan them. Most of the flooring guys used them. Some didn't. Make sure you check your rises if you are switching tread thicknesses.
Also, you mention that your treads are 12" wide. Treads generally need to be ripped to the right width, as max overhang by code is 1 1/4". And by code, max difference in tread width is 3/8" overall and in my state, no more than 3/16" between 2 adjoining treads. This also applies to riser.
Contributor R, your statement, "Many times on framer built stair carriages, adjustments must be made to be in code" has to be the understatement of the year! Adjustments? Yeah right! Rebuilding would be more like it. I swear, I get so frustrated and angry I could spit nails every time I have to re-build some hack framer's excuse for stringers! I wish the builders would call me to rough in the stairs. Would save me a lot of frustration later on down the road.