Triangles, crescents, slivers: Can odd-shaped lots help ease US housing crisis?

The Corvidae Co-op has 10 units on two single-family lots. — Photos: RUTH FREMSON/The New York Times

Triangular plots from old railroad lines. Crescent-shaped parcels that used to be parking lots. And narrow strips of land squeezed between buildings.

For decades, builders ignored irregular lots in the United States, typically smaller and narrower than standard square ones, because of zoning codes and rules.