Skewed walls are a major challenge in rebuilding stairs. For example, in Project 2,  the wall sloped more than 3/4" in an 8 foot rise! That meant that wall had to be rebuilt. In Project 1,  we had to determine if the wall on the left was weight bearing or not, without bringing the house down.

Even in the best cases, each tread must be cut with care, and to fit its specific location. Rises inevitably have to be adjusted to fit the house. And it all has to be done so it looks right to the eye. It takes more math than you'd think, and a good sense of style. There is as much art involved  as there is  skill, and there's quite a bit of skill.

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