Conventional, Veneer and Venetian Plaster
The use of gypsum plaster dates back to 4000 B.C., when the Egyptians applied a plaster-like substance to the pyramids. Gypsum was eventually brought to the United States in the 1700s as a soil additive by Benjamin Franklin. Modern processing methods of the 20th century allowed gypsum plaster to be used extensively in commercial and residential projects.

Gypsum plaster provides effective acoustic and fire resistance and is suitable for all interior plastering, except where directly exposed to wet conditions. Gypsum plasters are not suitable for exterior applications.

Conventional Lath and Plaster systems have been the industry standard for wall construction for many years. It begins with a scratch coat, made up of gypsum plaster and sand, over some type of base. One hundred years ago this base was made of wood lath, brick or clay tile. Thirty five years ago it may have been metal lath, block, tile or rocklath, which is a 3/8” sheet measuring 16” x 48” that looks similar to drywall. Today this base would be metal lath or gypsum board, similar to drywall, but with different paper.    

Once the scratch coat has cured, a brown coat (consisting of gypsum and sand) is applied. The brown coat can be applied in one or two coats to get the desired thickness.

The finish coat is applied last and between 1/16 to 1/8”. It normally consists of lime and a catalyst to help it set.

Veneer Plaster consists of a thin base and finish coat (1/8 – 3/16” total), which is applied over a gypsum base called blue board. Blue board is similar to drywall, but has a special paper that ensures a proper bond with plaster.

Veneer systems help eliminate nail-pops and ripples often seen in drywall applications. They also have slightly better acoustic values.

Venetian Plaster or Veneziano, has been used for thousands of years. It is the most beautiful and luxurious finish available. It consists of crushed marble, aged lime and natural pigments. (Do not confuse with Venetian paint or faux plaster.) Depending on application style, Venetian plaster can be compared to polished marble and is stunning in its appearance.

Venetian plaster has great design capabilities and can offer an “old world” look or enhance a contemporary project.

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