home owner and the plasterer's boss will usually decide beforehand what styles they will use in the house. Typically walls are smooth and sometimes ceilings. Usually a homeowner will opt to have the ceilings use a "texture" technique as it is much easier, faster, and thus cheaper than a smooth ceiling. The plasterer quotes prices based on techniques to be used and board feet to be covered to the contractor or homeowner before work begins. The board feet is obtained by the hangers or estimated by the head subcontractor by counting the wallboards that come in an industry standard of 8' to 12' long. He then adds in extra expenses for soffits and cathedral ceilings. Ceiling second or first Typically if the ceiling is to be smooth it is done first, before the walls. If it is to be textured, it is done after the walls. The reason for this is that invariably when a ceiling is being worked on plaster will fall and splash onto the walls. However a texture mix doesn't need to be smoothed out when it starts to set: thus a retardant such as "Cream of tartar" or sugar can be used to prolong the setting time, and is easily scraped off the walls. and since time is not as restraining of a factor on textured ceilings a large mix, or back-to-back mixes can be done and all ceilings covered at the same time. another reason is that a bird is usually run along the top corner after doing a smooth ceiling, then it is easier to maintain this edge by doing the wall last. But a textured ceiling normally doesn't need to be birded, only blended in with a very wet paint brush. In this case the wall is done first and the corner formed with the bird. Scratching The first thing the plasterer tends to do is go over all the mesh-taped seams of the walls he is about to cover; in a very thin swatch. The wallboard draws moisture out of this strip so when the plasterer goes over it again when doing the rest of the wall it will not leave an indented seam that needs further reworking. He then fills in the area near the ceiling so he will not have to stretch to reach it during the rest of the wall; And he forms the corner with his bird. This