I’d put a handrail on the other side, miter it at the corner and go up to the window trim. That would move your travel path to the widest part of the treads and get you nearly to the top. If that feels unsafe, offset the upper part of the handrail to extend across the window with enough hand clearance at the window trim.

I agree with the handrail. Also, put transparent anti slip treads for wooden stairs. https://www.amazon.com/Transparent-Non-Slip-Carpet-Resistance-Outdoor/dp/B07JL5XNHM/ref=asc_df_B07JL5XNHM/?tag=hyprod-20&linkCode=df0&hvadid=309816949166&hvpos=&hvnetw=g&hvrand=326229178925205246&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1022672&hvtargid=pla-570011675749&psc=1 Another thing you can do is make sure every member of the family wears sneakers each time using the stairs.

In that situation I would not hesitate to put a handrail in from the top to the bottom, going right across the window.

I would put a handrail on the left hand wall (outer) going up, and put it across the window at the top.

A handrail where it seems to want to be so think about how you use the stairs this was an old building I bet where stairs were not onlysteep and narrow but were done to fit the space not a design element I am not sure this was done later I agree the handrail needs to be continuous not and running across the window would probably work best.

I call steps like that ass-busters. Another vote for handrails or grab bars on the opposite wall.

Adding a handrail is not considered to be a stair modification. It’s a much needed improvement but will most likely not be code compliant with the angle and configuration of the stairs. I would hope some common sense will prevail.

The IRC addresses each component of a stairway separately. Just by adding a handrail would not trigger an upgrade to the treads and risers. Most here would agreed this would not be possible in this instance within the given limited space. As a building inspector, I would encourage the addition of a handrail, even if it can’t maintain the required height for the full run of stairs. I still hope some common sense would come into play and allow any upgrade that provides some safety measures. In your personal situation, because you changed the existing handrail, it would then need to meet code. I would have required the continuous handrail too.

Those are common steps in same era rowhouses in downtown Baltimore.

Steps were walled in and there wasn‘t any woodwork. The stairs might have originally not had any handrail, a continous handrail or, very likely, one or two grab-bars at strategic locations on the walls.