Today work started on the stairs. And that involves each tread coming off, being sanded and put back on again. As we're still living here and still need to get up the stairs that means every other tread has been removed, on both flights. Here's looking up from the first floor:
And looking back down to the ground floor:
From the bottom you can see the "step" we have to take:
Already I've discovered going up I lead with my right leg and coming down with my left. I assume that's so my foot is on the wider part of the tread, but it was something I did without thinking about. It does mean going up the stairs (or down them) in a hurry isn't going to happen until they're back in place.
Now we have random piles of treads around the place: