Clay walls can be found in both old and new buildings. Clay is an environmentally friendly material, and its properties help keep the interior warm in the winter and cool in the summer. I've read that adobe walls can be finished with mixtures that are lighter in dry weight than clay, otherwise they will peel. My experience plastering clay is in this video. I believe this clay wall plastering technique is applicable to adobe, adobe, and clay-plastered walls. The video also shows how to attach reinforcing mesh to the wall. This is the resulting plastering of an old clay house.

0:08 Types of Clay Houses
0:22 How to Remove Whitewash from a Clay Wall
2:05 How to Patchy Large Cracks in a Clay Wall
2:50 How to Patchy a Clay Wall
3:32 What Mesh to Use for Plastering Clay Walls
4:13 How to Attach Plaster Mesh to a Clay Wall
4:29 How Many Dowels Are Needed to Attach Plaster Mesh
4:48 How to Attach Plaster Mesh with Dowels
5:07 How a Dowel Works for Attaching Plaster Mesh
6:06 What to Do if the Dowel Doesn't Hold in the Wall
7:24 Plastering a Clay Wall on Mesh
7:29 What Layer of Plaster to Apply to the Mesh
8:12 What Size of Grouting Mesh to Use
8:17 Troweling Tool
9:13 Why Prime a Wall Before Plastering
10:03 What Mesh to Use for the Finish rubbing
10:40 Why you shouldn't prime the finishing coat with concentrated primer
11:07 What paint to use on exterior walls