It should adhere to the background and should remain adhered to during all variations of the climate changes. Also, it should be possible to apply it during all weather conditions.
It should not contract in volume while drying and setting. Otherwise, it will crack and give an unsightly appearance.
It should be cheap and economical.
It should be hard and durable, providing a smooth, non-absorbent, and washable surface with required decorative effect and durability.
It should offer good insulation against sound and high resistance against fire.
It should effectively check the entry or penetration of moisture from the surface.
Movements in the backing either on account of thermal expansion or due to shrinkage caused by the drying of the backing material. To avoid this the backing surface should be allowed to dry before applying the plaster.
Movement in the plaster itself on account of the expansion (in case of gypsum plaster) or shrinkage of the plaster coat (in case of lime-sand plaster) during drying.
Excessive shrinkage of plaster due to the application of mortar in thick coats.
Workmanship and the method of application of the plaster. Rough textured finishes are generally less likely to show cracking than smooth finishes.
The adhesion of the plaster to the back-ground may not be perfect.
The suction of the backing material may not be uniform. At places where the backing material absorbs an excessive amount of water, the plaster loses its strength as well as the mechanical bond between the two surfaces.
Excessive thermal changes in plaster or backing.
The bond between the successive cost of plaster may not be perfect.