These walls are typically called "lath and plaster." A lath is a narrow slat of wood. https://en.wikipedia.org/wiki/Lath_and_plaster https://en.wikipedia.org/w

These walls are typically called "lath and plaster." A lath is a narrow slat of wood. https://en.wikipedia.org/wiki/Lath_and_plaster https://en.wikipedia.org/wiki/Lath_and_plaster