He is wrong.
Laying down the 2x12 carpet-ready treads is part of framing, not finish.
(At least where I come from).
This should be specified in the contract.
Step in that 4" gap and threaten to sue him if he doesn't come back and finish the job.

And, why would you have him do any more work for you with the past problems?

 

Please don't refer to him as a contractor, it gives good contractors a bad name. Please use the term 'Hack'. Thank you.

 

Hack.

 

How about pics.....I have a feeling you have more problems than just being 'carpet ready'.

I made the stairs for my 2nd floor a couple months ago....2x14" stringers 12" OC...treads are 1 1/8" plywood with 3/4" risers. Here are a couple of pics.

Mine are 'carpet ready' but will not get carpet....I'll be putting down oak with a carpet runner on top.

 

From your pics, it doesn't look like you incorporated an overhang on the front stair treads (nosings).

As long as you are installing finish-treads and finish-landing-sections, that should work, but "carpet ready" includes treads and landing segments with at least a 1" nosing overhang.

Example:

Nose depth of 3/4 inch to 1-1/4 inch is usually acceptable. I typically use a nose depth of one inch when designing stairs.

Example Link: http://www.hammerzone.com/archives/framecarp/technique/stairs/outdoor.htm

 

From your pics, it doesn't look like you incorporated an overhang on the front stair treads (nosings).

As long as you are installing finish-treads and finish-landing-sections, that should work, but "carpet ready" includes treads and landing segments with at least a 1" nosing overhang.

Example:
Example Link: http://www.hammerzone.com/archives/framecarp/technique/stairs/outdoor.htm

You are correct....so technically, my stairs are not carpet ready....but since the 1" overhang will be in the finish treads....I'm good to go...

 

Confusing, why OSB on the wall and not sheetrock?
Stringers tight to the wall so no room for skirts or sheetrock.
Threads tight to the walls.
Seem to be missing a couple of walls where the stairs turn.

 

OSB is there because that is a B shear wall....I had to rip out the floor there and pour a footing under that wall along with anchor bolts and HD5's at each end of the wall.

I have since put in a platform in the space between the stairs and wall....

What is not obvious....this used to be the master bedroom....those stairs are where the closet 'used' to be.....

 

Here's an update. I ended up getting rid of my contractor and finishing the stairs myself. It’s too bad that he did not complete this job as expected. It ended up costing us $200 to finish the stairs. We ended up completing the rest of the work ourselves instead of using the contractor. For $200, he probably lost $10,000. His loss was my gain because I saved a bunch of money on labor. I ended up siding my house myself using hardie board siding. In addition, I renovated the kitchen myself. Normally, I would have contracted this out. I can't imagine how much he would have charged for that. Anyway, here is how I finished them. We removed all of the 2x4 that the contractor used for stair treads. We added a 12" pine board down both sides the stairs. We bought stair treads and attached them to the stringers. We added a handrail down one side. There was a half wall along the other side so the inspector did not require us to install a second handrail. Right now, we just painted the stair treads and added some glue down carpet. Later this year, we plan to buy carpet and have it installed.