For homeowners

Types of plaster: which one suits your walls and ceilings?

Choose Lime plaster for the finish coat, as lime putty mixed with about 35 percent gypsum (gauging plaster) to help it harden (NPS, 1989); Gypsum plaster for decorative mouldings, as moulding plaster, a finer gypsum plaster used in ornamental plasterwork (NPS, 1989); Veneer plaster for new panels over furring channels on masonry walls, or over old wood lath walls and ceilings (NPS, 1989).

The right choice depends on which part of the work it is (a finish coat, decorative mouldings or new panels) and how much water reaches the wall behind the plaster.

How we know: By InstaBids editorial team with AI research agents. · Sources read: 22 October 2026 · Updated 27 October 2026

Plasterers in North America have relied on two materials, lime and gypsum (NPS, 1989). Veneer plaster is the modern replacement system the National Park Service brief Repairing Historic Flat Plaster describes, with gypsum-core panels and thin coats of plaster.
Type	Best for	Main advantages	Main drawbacks
Lime plaster	the finish coat, as lime putty mixed with about 35 percent gypsum (gauging plaster) to help it harden (NPS, 1989)	lime plasters could survive occasional wind-driven moisture or water wicking up from the ground (NPS, 1989)	a lime-plastered wall could take more than a year to dry, which delayed painting or papering (NPS, 1989)
Gypsum plaster	decorative mouldings, as moulding plaster, a finer gypsum plaster used in ornamental plasterwork (NPS, 1989)	gypsum begins to cure as soon as it is mixed with water; it sets in minutes and completely dries in two to three weeks (NPS, 1989); molding plaster is finely ground to accept the detail of rubber molds, not so hard as to prohibit tooling, and combines readily with finish lime (NPS, 1990)	gypsum plaster needed protection from water: furring strips had to be used against masonry walls to create a dead air space (NPS, 1989)
Veneer plaster	new panels over furring channels on masonry walls, or over old wood lath walls and ceilings (NPS, 1989)	although extremely thin, a two-coat veneer plaster system has a 1,500 psi rating and is able to withstand structural movements in a building (NPS, 1989); the room will be ready for painting almost immediately, and the troweled or textured surface looks more like traditional plaster than drywall (NPS, 1989); insulation can be installed between the pieces of furring channel used to attach the veneer panels (blueboard) to masonry walls (NPS, 1989)	no official source names one

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Sources for the facts on this page

U.S. National Park Service, Technical Preservation Services, Preservation Brief 21: Repairing Historic Flat Plaster - Walls and Ceilings (October 1989), government, read 22 October 2026.
U.S. National Park Service, Technical Preservation Services, Preservation Brief 23: Preserving Historic Ornamental Plaster (October 1990), government, read 22 October 2026.