Additives to plaster designed to make them lighter and/or stronger,
usually sand, vermiculite, or pumas/volcanic ash. Aggregates prevent
shrinkage by making efficient use of binder materials.
Like drywall, a gypsum-based board with blotter paper to accept
modern plaster to adhere to.
Base coat plaster in a multi-coat system. Sometimes applied over
the scratch coat in a 3-coat application, or the base before a topcoat
A water-soluble coating comprised calcium carbonate (carbonated
chalk) that was used as a quick and economical coating over walls and
Plastic or metal termination of an edge that can be either 90 degrees
or bullnose (rounded). To withstand impact without ruining the plaster
that joins it.
Goes in interior corners beneath the plaster to prevent cracking.
A brand name for a setting joint compound. Has gypsum crystals that
make it set like plaster, and bonding agent that makes it stick like
An organic material, called calcium sulfate in its original form.
It is mined and processed crystal that is the industry standard for
modern lath wallboard plaster It is a substrate material as well as
an active ingredient in modern plasters.
A one-handed tool used to hold plaster for hand tooling and troweling.
Designed for use with drywall, a water-soluble binder with inert,
non-reactive compound used for filler.
Parts of plaster that go through openings in wood or wire lath and
curl over to assist the plaster in holding onto the substrate.
A substrate material for plaster. Wood or wire or gypsum core board,
it provides the base for plaster to adhere to either through use of
keys or other mechanical bond.
Final step in finishing the plaster topcoat involving a final scrape
with the trowel to remove irregularities, fill void, compressing the
surface of the plaster to create a glass-like finish.
An adhesive process whereby plaster that has pulled away from its
substrate is glued back in place with the use of acrylics and mechanical
means push the plaster back in place.
The first coat of plaster in a multi-coat system. The wet plaster
is "scratched" with the trowel or a comb to provide a rough
surface to give tooth for the next layer of plaster to adhere to.
Coating an entire area with a thin coat of material.
Also known as active lime or lime putty. Lime that has been processed
(burned) and had water added to it, but has not received its final set
through chemical reaction with carbon dioxide to bring it back to lime
stone (calcium carbonate).
The physical base that plaster or other finishes attach to either
mechanically or physically.
The final coat in a plaster system, which could be veneer plaster,
lime or lime and gauging plaster, or lime and sand plaster depending
on the system.
A thin coat of plaster, designed for newer blueboard plaster systems.
A coating made of active lime and water used to coat plaster, wood
and masonry. A home brew, it was sometimes used as a germicide, including
such chemicals as formaldehyde and copper sulfate.