National Gypsum Construction Guide - 12th Edition

Key to Federal Specification Designations
GYPSUM BOARD PRODUCTS
Types–Grades–Classes–Forms–Styles
Type Grade Class Form Style
TYPE I R-Regular core 1-Plain face a-Plain back 1-Square edge
Lath X-Fire-retardant core b-Perforated
c-Foil back
5-Round edge
TYPE II R-Regular core 2-Water-resistant surface a-Plain back 1-Square edge
Sheathing W-Water-resistant
treated core
X-Fire-retardant core
2-V-tongue and groove edge
TYPE III R-Regular core 1-Plain face a-Plain back 1-Square edge
Gypsum Board X-Fire-retardant core 3-Predecorated surface c-Foil back 3-Taper or recess edge
4-Featured joint edge
6-Taper, featured edge
TYPE IV R-Regular core 1-Plain face a-Plain back 1-Square edge
Backer board X-Fire-retardant core c-Foil back 2-V-tongue and groove edge
3-Taper or recess edge
TYPE V
Formboard
R-Regular core 4-Fungus-resistant surface a-Plain back 1-Square edge
TYPE VI R-Regular core 1-Plain face a-Plain back 1-Square edge
Veneer X-Fire-retardant core c-Foil back 3-Taper or recess edge
Plaster Base 6-Taper, featured edge
TYPE VII R-Regular core 2-Water-resistant surfaces a-Plain back 1-Square edge
Water-resistant W-Water-resistant 3-Taper or recess edge
Backing Board treated core
X-Fire-retardant core
As an aid in the identification of gypsum board products, above are the classifications as set forth in Federal Specification SS-L-30D.
JOINT TREATMENT PRODUCTS
Types–Styles–Classes
Type Style Class
TYPE I 1-Drying powder A-Taping
Joint Compound B-Topping
C-All purpose
2-Hardening powder A-Taping
B-Topping
C-All purpose
3-Drying, premixed paste A-Taping
B-Topping
C-All purpose
TYPE II
Joint Tape
1-Plain
As an aid in the identification of joint treatment products, above are the classifications as set forth in Federal Specification SS-J-570B.
GENERAL REFERENCE
NATIONAL GYPSUM PRODUCT SPECIFICATION DIRECTORY
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GENERAL
REFERENCE