or "plaster and lath" is an old fashioned technique for finishing interior walls. It consists of horizontal strips of wood (the laths) nailed to the stud work and then that is plastered.

This technique for plastering interior stud walls and ceilings has been virtually replaced by or plasterboard.

The plaster was often mixed with a binding agent - usually horsehair - to ensure that it was sufficiently stiff to cover the laths.