2.7
GYPSUM LATH AND VENEER PLASTER BASE
2.7.1
Gypsum Lath
Gypsum lath shall conform to ASTM C 37/C 37M. Lath shall be [plain]
[aluminum foil backed] [Type X] [lead-backed for control of X-ray
transmission] designed to be used as a base for gypsum plaster.
2.7.2
Veneer Plaster Base
Veneer plaster base shall conform to ASTM C 588/C 588M. Base shall be
[aluminum foil backed] [Type X], and shall be designed to be used as a base
for gypsum veneer plaster.
2.8
GYPSUM PLASTER
2.8.1
Ready-Mixed Gypsum Plaster
[Ready-mixed plaster for use over gypsum or metal lath shall conform to
ASTM C 28/C 28M for the following: ready-mixed plaster with vermiculite
aggregate; ready-mixed plaster with perlite aggregates; ready-mixed plaster
with sand aggregate.] [Ready-mixed gypsum plaster for use over masonry
bases shall conform to ASTM C 28/C 28M for plaster with vermiculite
aggregate.] [Ready-mixed plaster for use over veneer plaster bases shall
conform to ASTM C 587.]
2.8.2
Gypsum Neat Plaster
Gypsum neat plaster shall conform to ASTM C 28/C 28M.
2.8.3
Gypsum Wood-Fibered Plaster
Gypsum wood-fibered plaster shall conform to ASTM C 28/C 28M.
2.8.4
Gypsum Gauging Plaster for Finish Coats
Gypsum gauging plaster shall conform to ASTM C 28/C 28M. Keene's quick-set
cement for finish coats shall conform to ASTM C 61/C 61M.
2.9
CEMENT PLASTER MATERIALS
2.9.1
Portland Cement
Portland cement shall conform to ASTM C 150, [gray portland cement Type
[I], [II], [III]] [white portland cement Type [I] [II]] with 13 mm 1/2 inch
chopped alkali-resistant fiberglass strands or polypropylene fibers,
minimum 680 g 1-1/2 pounds per sack of cement.
2.9.2
Aggregates
The unit weight of aggregates shall be determined in accordance with ASTM C
29/C 29M. Gypsum aggregates shall conform to ASTM C 35. Portland cement
based plaster aggregates shall conform to ASTM C 897, except that the
gradation of natural or manufactured sand for portland-cement plaster shall
be as follows:
SECTION 09200A
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