National Gypsum facebook National Gypsum twitter
Bookmark and Share
New Innovative Products
GridMarX Gypsum Board
Customer Service & Product Availability Information
Code Reports
General Terms and
Conditions of Sales


Cavity Shaftwall Systems


Gypsum drywall shaft construction has become the preferred alternative to traditional masonry shafts. One-inch Shaftliner board was developed as a lightweight, easy-to-install replacement for masonry in the interior core of buildings for shaftwalls, stairwells, other vertical chases and mechanical enclosures. Shaftliner board is also used as a component of 2" solid partitions, and area separation walls with a layer of 1/2" Regular or Fire-Shield Gypsum Board attached to each side.

Historically, heavy masonry weighing 20 to 45 lbs. per square foot was used for shaftwall construction. With the use of Shaftliner, shaftwall assemblies weigh in at a remarkably low 10 to 13 lbs. per square foot.

The benefits of gypsum drywall shaft systems go far beyond the difference in weight alone. The core wall of a shaft can be installed from the exterior of the shaft and requires no scaffolding. Erection is speedy and clean. Shaftliner also provides excellent sound control and can achieve the fire ratings necessary for today's building construction. Best of all, gypsum shaftwall systems are more economical than masonry shaft construction.

National Gypsum produces Shaftliner board with green moisture resistant paper, PURPLE® moisture/mold/mildew resistant pape, or fiberglass facer on both sides with a beveled edge configuration allowing for simple installation into the Shaftwall System framing.

Cavity Shaftwall systems are a nonload-bearing drywall partition made up of two basic components, gypsum board and metal framing. Gypsum board includes 1" Fire-Shield Shaftliner, 1" Fire-Shield Shaftliner XP panels, 1" eXP Shaftliner panels, 1/2" Fire-Shield C and 5/8" Fire-Shield Gypsum Board face panels. 1/2" XP Fire-Shield C or 5/8" XP Fire-Shield Gypsum Board face panels may be utilized for extra protection against mold and mildew. The framing includes I-Studs, C-T Studs and C-H studs with integral tabs/flange which hold the panels in place and J Track for runners at top and bottom, as well as vertically at partition ends and to frame openings.

Code Report

ICBO ES, Inc. ER-3579
Gold Bond I-Stud Cavity Shaftwall System and Horizontal Shaftwall Systems

Basic Uses

  • The Cavity Shaftwall system was developed to enclose elevator shafts and other vertical chases in buildings where it is advantageous to erect these walls from one side only and where fire resistance and resistance to air pressures are required.

Note: Cavity Shaftwall Systems have been tested as complete assemblies. Substitution of components may adversely affect system performance. For information on system requirements contact National Gypsum's Technical Service at 1-800-NATIONAL® (1-800-628-4662).


  • Although the Cavity Shaftwall system is nonload-bearing, this system has been designed and tested to withstand positive and negative air pressure forces exerted by high-speed, high-rise elevators.
  • The Cavity Shaftwall systems have been fire tested and achieved fire resistance ratings of 1 to 4 hours. All components are noncombustible.
  • The Shaftwall system is very lightweight compared to conventional shaftwalls, weighing approximately 10 lbs. per sq. ft. of wall when finished with two layers of 1/2" Fire-Shield C Gypsum Board.
  • Shafts can be quickly enclosed with shaftwall framing and Shaftliner under most conditions in which installers can work, well before temperature limitations for finish gypsum board applications.
  • 1" Shaftliner is faced with light green moisture resistant pape, Shaftliner XP is faced with PURPLE® moisture/mold/mildew resistant paper, amd eXP Shaftliner is faced with PURPLE® moisture/mold/mildew/resistant fiberglass facer for protection against weather during installation.


09 21 16.23
Technical Data
CSI 3 Part Specifications   PDF
Checked items above will be available for email and download on the Submittal Builder page.