Lath and plaster is a way of covering the walls and ceilings in old houses. It involves putting thin pieces of wood called lath onto the walls and then covering them up with a special gooey material called plaster.
The lath is kind of like a frame for the plaster. It helps the plaster stick to the wall and stay in place. The lath is put up in a criss-cross pattern so that it is strong enough to hold the plaster.
Once the lath is up, it's time to put on the plaster. The plaster is mixed up with water until it is a creamy consistency. Then it is spread onto the lath with a tool called a trowel. It takes a lot of skill to spread the plaster evenly and smoothly.
After the plaster is on the wall, it needs to dry. This can take a long time because the plaster is thick and needs to dry all the way through. Once the plaster is dry, it can be painted or decorated however the homeowner wants.
Lath and plaster was a popular way to cover walls and ceilings in old houses because it was affordable and durable. However, today many houses use different methods like drywall or plasterboard instead.