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Armstrong Delivers Tested Solutions
Armstrong has conducted rigorous full-scale seismic testing at the State University of New York, University at Buffalo to
demonstrate seismic performance. IBC code allows alternative designs if tests are conducted and evidence of compliance is
submitted.
Click here for a list of Armstrong Seismic Tested Products.
Seismic Rx®
ICC-ES recognizes Armstrong Seismic Rx Suspension System as a code compliant solution (ESR-1308). This evaluation and confirmation
by ICC-ES provides evidence supporting the Armstrong Seismic Rx Suspension System as a code-compliant alternative to IBC requirements.
The performance of the Armstrong Seismic Rx System is based on a specific combination of components and methods of installation.
ESR-1308 allows you to meet seismic code without the risk of delaying your construction schedule.
Click here for more information on ESR-1308.
Purpose of Installation Requirements for Suspended Ceilings
- Suspension systems strong enough to resist lateral forces imposed upon it without failing
- Prevent border panels from falling from the ceiling plane
Federal Emergency Management Agency (FEMA)
Seismic performance during recent large California earthquakes prompted FEMA to address several concerns including suspended
ceiling performance during a seismic event. Research and tests demonstrated that current industry seismic standards (UBC Standard
25-2) were not adequate. To support individual panels around the perimeter, FEMA determined that the key to good seismic performance
is a wider wall molding on all sides. This led to the International Building Code requirement for 2" wall molding on all sides.
(Source: FEMA 302 NEHRP Recommended Provisions for Seismic Regulations for New Buildings and Other Structures)
How Seismic Design Categories Are Determined
The seismic design category must be specified by a professional engineer or registered architect on the project drawings per
CISCA 0-2, 3-4. The project requirements which include the seismic design category can be found in Section 1 of the specification
and on the first page of the structural drawings.
International Building Code (IBC) allows two paths to determine Seismic Design category - IBC Section 1613 or ASCE 7 Section
11.6. The IBC states that a Seismic Design Category must be established for each construction project based on:
- Anticipated ground motion
- Soil type in a specified geographic area
- Occupancy category
These factors are used to evaluate and establish a Seismic Design Category of A, B, C, D, E or F. The installation of ceilings
can be divided into three tiers of increasing requirements:
- Categories A & B are installed to meet requirements established in ASTM C636
- Category C projects must meet those plus additional provisions listed in the CISCA recommendations for areas subject to moderate
risk
- Categories D, E & F must follow ASTM C636, CISCA guidelines for areas subject to severe earthquake risk and eight additional
provisions contained in ASCE 7 Section 13.5.6.2.2
Note: Seismic categories are determined for the entire building. This is why the Seismic Design Category information is on
the structural drawings.
Seismic Separation Joints
ASCE 7 Section 13.5.6.2.2 mandates that ceiling areas greater than 2500 SF must have seismic separation joints. Armstrong
has done full-scale testing which confirms that a ceiling fitted with our Seismic Joint Clip for Main Beams (SJMR) and Seismic Joint Clip for Cross Tees (SJCG & SJCSI) performs as well as a field fabricated separation joint. Additional benefits to these seismic-tested separation joints:
Seismic Joint Clip – Main Beam (SJMR)
- Gives architects and designers a clean look (not visible from the floor)
- Saves contractors time with a reliable installation method
- Easily installs in minutes at main beam splice
- Maintains integrity of ceiling module, unlike field assembled alternatives
- Allows for full acoustical panel at the joint
- Easier to keep the ceiling system square
Seismic Joint Clip – Cross Tee (SJCG & SJCSI)
- Gives architects and designers a clean look (not visible from the floor)
- Saves contractors time with a reliable installation method
- Installs in minutes, no need to cut the face of the grid to install clip
- Eliminates the need for additional hanger wires
- Maintains integrity of the ceiling module, unlike field assembled alternatives
- Allows the use of full size panels
- Works with our PeakForm® grid (Suprafine®, Prelude®) and square bulb grid (Silhouette® and Interlude®)
CES Course
Ask us about our new CES course on current seismic code requirements for commercial ceiling systems. Contact your Armstrong rep or call 877-ARMSTRONG for more information.